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1.
Journal of Forensic Medicine ; (6): 151-160, 2023.
Article in English | WPRIM | ID: wpr-981849

ABSTRACT

OBJECTIVES@#To establish an LC-MS/MS method based on single hair micro-segmental technique, and verify the detection of 42 psychoactive substances in 0.4 mm hair segments.@*METHODS@#Each piece of single hair was cut into 0.4 mm segments and extracted by sonication and the segments were immersed in dithiothreitol-containing extraction medium. Mobile phase A was the aqueous solution containing 20 mmol/L ammonium acetate, 0.1% formic acid, and 5% acetonitrile. Mobile phase B was acetonitrile. An electrospray ionization source in positive ion mode was used for data acquisition in multiple reaction monitoring (MRM) mode.@*RESULTS@#The 42 psychoactive substances in hair had a good linear relationship within their respective linear ranges (r>0.99), the limits of detection were 0.2-10 pg/mm, the limits of quantification were 0.5-20 pg/mm, the intra-day and inter-day precisions were 1.5%-12.7%, the intra-day and inter-day accuracies were 86.5%-109.2%, the recovery rates were 68.1%-98.2%, and the matrix effects were 71.3%-111.7%. The method was applied to hair samples collected from one volunteer at 28 d after a single dose of zolpidem, with zolpidem detected in 5 hairs was 1.08-1.60 cm near the root tip, and the concentration range was 0.62-20.5 pg/mm.@*CONCLUSIONS@#The micro-segmental technique of single hair analysis can be applied to the investigation of drug-facilitated sexual assault cases.


Subject(s)
Humans , Chromatography, Liquid/methods , Zolpidem , Tandem Mass Spectrometry/methods , Hair , Acetonitriles , Chromatography, High Pressure Liquid
2.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 364-366, 2023.
Article in Chinese | WPRIM | ID: wpr-986014

ABSTRACT

Objective: To establish a method for the rapid determination of acetaminophen (APAP) in human plasma by LC-MS/MS. Methods: The plasma samples were extracted by methanol and acetonitrile (1: 1) and purified directly. C(18) column was used for sample separation. The mobile phase were methanol (5 mmol/L ammonium acetate) and water (5 mmol/L ammonium acetate). Samples were analyzed by LC MS/MS with the electrospray ionization multi reaction monitoring (MRM) mode. Results: The calibration curves of APAP was linear in the concentration range of 0~10 mg/L, the correlation coefficient (r) was greater than 0.999 0. The relative standard deviation within and between batches was less than 10%. The recovery rate were 96.81%~101.7%. The detection limit of the method was 0.1 μg/L and the lower limit of quantification was 0.3 μg/L. Conclusion: This method has strong specificity, high sensitivity and reliable determination results. It is suitable for the rapid analysis of clinical plasma samples.


Subject(s)
Humans , Chromatography, Liquid/methods , Acetaminophen , Tandem Mass Spectrometry/methods , Methanol , Chromatography, High Pressure Liquid/methods
3.
Braz. J. Pharm. Sci. (Online) ; 59: e21283, 2023. tab, graf
Article in English | LILACS | ID: biblio-1439509

ABSTRACT

Abstract The anecdotal use of Alternanthera sessilis L. as a relief for diabetes has been known in the Philippines for generations, and antidiabetic activity of similar varieties in other countries is likewise documented. However, the compounds responsible for this activity remain unclear. This study aims to isolate the anti-hyperglycemic fraction of local A. sessilis leaves and identify the compounds in this fraction. Methanol extract of A. sessilis leaves and its hexane, ethyl acetate (ASE), and water fractions were administered to alloxan-induced diabetic mice. ASE (250mg/kg) had the highest anti-hyperglycemic activity at 6-h post-treatment (25.81%±12.72%), with almost similar blood glucose reduction rate as metformin (30.13±3.75%, p=0.767). Repeated fractionation employing chromatographic separation techniques followed by in vivo anti-hyperglycemic assay yielded partially purified subfractions. A. sessilis ethyl acetate subfraction 4-2 (100mg/kg) displayed remarkable suppression of blood glucose rise in diabetic mice at 6-h post-treatment (26.45±3.75%, p<0.0001), with comparable activity with metformin (100mg/kg, 27.87±5.65%, p=0.652). Liquid chromatography/mass spectrometry showed eight distinct peaks, with four peaks annotated via the Traditional Chinese Medicine library and custom library for A. sessilis. Among these, luteolin, apigenin, ononin, and sophorabioside were identified as putative compounds responsible for the anti-hyperglycemic activity. This result provided basis for the reported anecdotal claims and potential utility of the local variety of A. sessilis leaves as sources of anti-hyperglycemic agents


Subject(s)
Animals , Male , Female , Mice , Mass Spectrometry/methods , Biological Assay/methods , Plant Leaves/classification , Amaranthaceae/adverse effects , Chromatography, Liquid/methods , Apigenin/agonists
4.
Braz. J. Pharm. Sci. (Online) ; 59: e21626, 2023. tab, graf
Article in English | LILACS | ID: biblio-1429969

ABSTRACT

Abstract n our study, we aimed to validate a method based on liquid chromatography-mass spectrometry (LC-MS) to quantify spironolactone (SPI) and its active metabolite canrenone (CAN) simultaneously in plasma samples to support in vivo experiments. Compounds were separated by using a C18 column with the isocratic elution of a mobile phase composed of 0.1% (v/v) formic acid in methanol-water (60:40 v/v) at a flow rate of 0.4 mL min−1. SPI and CAN were detected in na electrospray interface operating in a positive ionization mode and quantified using the selective ion mode monitoring of mass-charge ratios (m/z) of 439.0 for SPI and 363.1 for CAN. After calculating the matrix effect using theoretical equations, we observed the strong interference of plasma in the equipment-generated signal, which required creating analytical curves using the matrix as a solvent. The method was nevertheless linear (r 2 > 0.999) in a concentration range of 0.4-5.0 µg mL−1, as well as precise, with a coefficient of variation less than 5%. SPI's and CAN's recovery rates from the plasma ranged from 87.4% to 112.1%, while their limits of detection (i.e., 0.07 µg mL−1 and 0.03 µg mL−1, respectively) and quantification (i.e., 0.20 µg mL−1 and 0.08 µg mL−1, respectively) in the presence of plasma contaminants were low. Therefore, the bioanalytical method seems to be feasible for quantifying SPI and CAN in plasma


Subject(s)
Plasma , Mass Spectrometry/methods , Spironolactone/analysis , Canrenone/analysis , Chromatography, Liquid/methods , Pharmacokinetics , Androgen Antagonists/adverse effects
5.
Braz. J. Pharm. Sci. (Online) ; 59: e21415, 2023. tab, graf
Article in English | LILACS | ID: biblio-1439525

ABSTRACT

Abstract Dasatinib, a potent oral multi-targeted kinase inhibitor against Src and Bcr-Abl, can decrease inflammatory response in sepsis. A simple and cost-effective method for determination of an effective dose dasatinib was established. This method was validated in human plasma, with the aim of reducing the number of animals used, thus, avoiding ethical problems. Dasatinib and internal standard lopinavir were extracted from 180 uL of plasma using liquid-liquid extraction with methyl tert-butil ether, followed by liquid chromatography coupled to triple quadrupole mass spectrometry in multiple reaction monitoring mode. For the pharmacokinetic study, 1 mg/kg of dasatinib was administered to mice with and without sepsis. The method was linear over the concentration range of 1-98 ng/mL for DAS in mice and human plasma, with r2>0.99 and presented intra- and interday precision within the range of 2.3 - 6.2 and 4.3 - 7.0%, respectively. Further intra- and interday accuracy was within the range of 88.2 - 105.8 and 90.6 - 101.7%, respectively. The mice with sepsis showed AUC0-t = 2076.06 h*ng/mL and Cmax =102.73 ng/mL and mice without sepsis presented AUC0-t = 2128.46 h*ng/mL. Cmax = 164.5 ng/mL. The described analytical method was successfully employed in pharmacokinetic study of DAS in mice.


Subject(s)
Animals , Male , Mice , Plasma , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Dasatinib/analysis , Pharmacokinetics
6.
Journal of Forensic Medicine ; (6): 34-39, 2023.
Article in English | WPRIM | ID: wpr-984177

ABSTRACT

OBJECTIVES@#To establish a method for the detection of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS).@*METHODS@#The blood samples were treated with 1-butyl-3-methylimidazolium hexafluorophosphate as an extraction solvent. The samples were extracted by ultrasound-assisted extraction and separated by ZORBAX Eclipse Plus C18, 95Å column. The mobile phase A aqueous solution containing 0.1% formic acid and 10 mmol/L ammonium acetate, and mobile phase B mixed organic solvent containing acetonitrile/methanol (Vacetonitrile∶Vmethanol=2∶3) were used for gradient elution at the flow rate of 1.00 mL/min. An electrospray ion source in positive mode was used for detection in the multiple reaction monitoring.@*RESULTS@#The linearities of carbamazepine and its metabolites 10,11-dihydro-10,11-epoxycarbamazepine and 10,11-dihydro-10-hydroxycarbamazepine in blood samples were good within the corresponding range, with correlation coefficients (r) greater than 0.995 6. The limits of detection were 3.00, 0.40 and 1.30 ng/mL, respectively. The limit of quantitation were 8.00, 1.00 and 5.00 ng/mL, respectively. The extraction recoveries ranged from 76.00% to 106.44%. The relative standard deviations of the intra-day and inter-day precisions were less than 16%. Carbamazepine and its main metabolite 10,11-dihydro-10,11-epoxycarbamazepine were detected in blood samples of death cases with a mass concentration of 2.71 μg/mL and 252.14 ng/mL, respectively.@*CONCLUSIONS@#This method has high sensitivity and good selectivity, which is suitable for the detection of carbamazepine and its metabolites in blood samples, and can be used for carbamazepine-related forensic identifications.


Subject(s)
Chromatography, Liquid/methods , Tandem Mass Spectrometry , Methanol , Carbamazepine/analysis , Benzodiazepines/analysis , Solvents , Chromatography, High Pressure Liquid , Solid Phase Extraction
7.
China Journal of Chinese Materia Medica ; (24): 1491-1497, 2023.
Article in Chinese | WPRIM | ID: wpr-970620

ABSTRACT

By investigating the contamination status and predicting the exposure risk of mycotoxin in Coicis Semen, we aim to provide guidance for the safety supervision of Chinese medicinal materials and the formulation(revision) of mycotoxin limit standards. The content of 14 mycotoxins in the 100 Coicis Semen samples collected from five major markets of Chinese medicinal materials in China was determined by UPLC-MS/MS. The probability evaluation model based on Monte Carlo simulation method was established after Chi-square test and One-way ANOVA of the sample contamination data. Health risk assessment was performed on the basis of margin of exposure(MOE) and margin of safety(MOS). The results showed that zearalenone(ZEN), aflatoxin B_1(AFB_1), deoxynivalenol(DON), sterigmatocystin(ST), and aflatoxin B_2(AFB_2) in the Coicis Semen samples had the detection rates of 84%, 75%, 36%, 19%, and 18%, and the mean contamination levels of 117.42, 4.78, 61.16, 6.61, and 2.13 μg·kg~(-1), respectively. According to the limit standards in the Chinese Pharmacopoeia(2020 edition), AFB_1, AFs and ZEN exceeded the standards to certain extents, with the over-standard rates of 12.0%, 9.0%, and 6.0%, respectively. The exposure risks of Coicis Semen to AFB_1, AFB2, ST, DON, and ZEN were low, while 86% of the samples were contaminated with two or more toxins, which needs more attention. It is suggested that the research on the combined toxicity of different mycotoxins should be strengthened to accelerate the cumulative exposure assessment of mixed contaminations and the formulation(revision) of toxin limit standards.


Subject(s)
Humans , Mycotoxins/analysis , Coix , Aflatoxin B1/analysis , Chromatography, Liquid/methods , Food Contamination/analysis , Tandem Mass Spectrometry/methods
8.
China Journal of Chinese Materia Medica ; (24): 366-373, 2023.
Article in Chinese | WPRIM | ID: wpr-970473

ABSTRACT

An analytical method for 10 mycotoxins in Hippophae Fructus medicinal and edible products was established in this study, and the contamination of their mycotoxins was analyzed. First of all, the mixed reference solution of ten mycotoxins such as aflatoxin, ochratoxin, zearalenone, and dexoynivalenol was selected as the control, and the Hippophae Fructus medicinal and edible products were prepared. Secondly, based on the ultra-performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS) technology, 10 mycotoxins in Hippophae Fructus medicinal and edible products were quantitatively investigated and their content was determined. Finally, the contamination of mycotoxins was analyzed and evaluated. The optimal analysis conditions were determined, and the methodological inspection results showed that the 10 mycotoxins established a good linear relationship(r>0.99). The method had good repeatability, test sample specificity, stability, and instrument precision. The average recovery rates of 10 mycotoxins in Hippophae Fructus medicinal products, edible solids, and edible liquids were 90.31%-109.4%, 87.86%-107.8%, and 85.61%-109.1%, respectively. Relative standard deviation(RSD) values were 0.22%-10%, 0.75%-13%, and 0.84%-8.5%, repsectively. Based on UPLC-MS/MS technology, the simultaneous determination method for the limits of 10 mycotoxins established in this study has fast detection speed, less matrix interference, high sensitivity, and accurate results, which is suitable for the limit examination of 10 mycoto-xins in Hippophae Fructus medicinal and edible products.


Subject(s)
Mycotoxins/analysis , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Hippophae , Limit of Detection , Chromatography, High Pressure Liquid/methods
9.
São Paulo; s.n; s.n; 2022. 63 p. tab, tab.
Thesis in Portuguese | LILACS | ID: biblio-1396298

ABSTRACT

Introdução: Meropenem (MER) e Piperacilina/Tazobactana (PTZ) são agentes antimicrobianos largamente prescritos para pacientes grandes queimados internados em Unidade de Terapia Intensiva (UTI) com infecções nosocomiais causadas por Gram-negativos sensíveis CIM 2 mg/L, Enterobacteriaceae, EB e Non-enterobacteriaceae, NEB. A síndrome da resposta inflamatória sistêmica (SRIS) que ocorre durante o choque séptico no grande queimado pode causar alteração na farmacocinética do paciente em terapia intensiva, de modo que a dose recomendada pode não atingir o alvo desejado contra Gram-negativos de sensibilidade intermediária CIM >2 mg/L. Objetivo: Investigar a efetividade dos beta-lactâmicos piperacilina e meropenem na infusão estendida comparada à infusão intermitente recomendada, para os pacientes sépticos grandes queimados através da abordagem farmacocinética-farmacodinâmica (PK/PD). Ética, casuística e procedimentos: Autor e co-autores declararam não haver conflito de interesse. O protocolo foi aprovado, registro CAAE 07525118.3.0000.0068. No presente protocolo de estudo investigaram-se 36 pacientes sépticos grandes queimados, ambos os gêneros (12F/24M) em terapia intensiva do choque séptico com piperacilina-tazobactana 4,5g q6h ou meropenem 1g q8h. Os pacientes incluídos foram estratificados em dois grupos com base na administração através da infusão intermitente, 0,5 h (G1) ou da infusão estendida, 3 h (G2), ambos com 16 pacientes cada. Duas amostras sanguíneas (1,5mL/cada) foram coletadas no estado de equilíbrio (Steady State), 3ª e 5ª hora do início da infusão. Os níveis séricos de PTZ e MER foram mensurados através de cromatografia líquida, e a farmacocinética (PK) dos dois grupos de pacientes foi comparada aos dados reportados em voluntários sadios. A abordagem PK/PD foi aplicada para avaliação da cobertura do antimicrobiano a partir da estimativa do índice de predição de efetividade (% fΔT>CIM) e da probabilidade de alcançar o alvo terapêutico (PTA) com base no alvo PK/PD recomendado, 100%fΔT>CIM. Resultados e discussão: As características de admissão dos pacientes G1/G2 foram expressas através de mediana e interquartil: Clcr 115 (90-148) / 127 (90-170) ml/min; 30 (24-31) / 27 (24- 33,5) anos, 70 (61-75) / 71 (65-75) kg, 30 (20-42) / 33,9 (18-38,4)% área total de superfície queimada, SAPS3 53 (45-57) / 48 (37,8-59,5). Na admissão dos pacientes na UTI registrou-se G1/G2: trauma térmico (17/16), trauma elétrico (1/2), lesão inalatória (11/11), ventilação mecânica (16/9) e vasopressores foram necessários em 15/8 pacientes, G1/G2. Ocorreram diferentes alterações na farmacocinética dos dois beta-lactâmicos após a infusão estendida versus a infusão intermitente quando comparadas com dados relatados em voluntários sadios. Evidenciou-se prolongamento da meia vida decorrente do aumento do volume de distribuição. Estes resultados impactaram diferentemente a cobertura. O monitoramento de biomarcadores inflamatórios expressos em medianas (G1/G2) evidenciou aumento do PCR: 232/183mg/L e leucocitose (leucócitos 11/14 mil cel/mm3, neutrófilos 9/10 mil cel/mm3) na fase precoce do choque séptico. Relativamente à microbiologia dos isolados, a erradicação dos patógenos ocorreu para todos os pacientes após a infusão estendida contra Gram-negativos sensíveis (CIM: 2 mg/L), e de sensibilidade intermediária (CIM 4mg/L) como a K. pneumoniae e P. aeruginosa, enquanto a infusão intermitente garantiu erradicação de patógenos apenas até CIM 2 mg/L. Conclusão: Evidenciou-se a superioridade da infusão estendida frente à infusão intermitente na cobertura dos dois antimicrobianos, no alvo terapêutico considerado 100%fΔT>CIM. Registraram-se alterações na farmacocinética destes agentes nos pacientes frente aos dados reportados para voluntários sadios. Diferença significativa entre grupos (G1/G2) foi encontrada com relação meia vida biológica, e ao volume de distribuição tanto pata a piperacilina quanto para o meropenem


Background: Meropenem (MER) and Piperacillin/Tazobactam (PTZ), antimicrobial betalactam agents are widely prescribed to burn patients from the Intensive Care Unit (ICU) with nosocomial infections caused by Gram-negative strains. Change in the pharmacokinetics of critically ill patient occurs during the systemic inflammatory response syndrome (SIRS) at the course of septic shock. Then, the recommended dose administered by intermittent infusion, 0.5 hr cannot reach the target against gram-negative strains MIC > 2 mg/L. Subject: To investigate drug effectiveness of the beta-lactams piperacilin and meropenem in extended infusion compared to the recommended intermittent infusion in critically ill septic burn patients using pharmacokinetic-pharmacodynamic (PK/PD) approach. Ethics, Casuistry and Methods: All authors declared there is no conflict of interests. Ethical approval CAAE, register 07525118.3.0000.0068. It was investigated in the study protocol 36 septic burn patients of both genders (12M / 24F), undergoing antimicrobial therapy with PTZ 4.5 g q6h or MER 1g q8h. Based on the chosen antimicrobial therapy and drug infusion prescribed by the physician, patients were stratified in groups with intermittent 0.5h infusion (G1) or with the extended 3h infusion (G2), both groups with 16 patients each. Two blood samples were collected at the steady state (1.5mL / each), at the 3rd and 5th hrs of starting the infusion. Serum levels were measured by liquid chromatography. Pharmacokinetics (PK) of MER or PTZ was compared to data reported in healthy volunteers for both groups of patients. PK/PD approach was applied to estimate the drug effectiveness index (fΔT> MIC) and to assess the probability of target attained (PTA) based on the recommended PK/PD target, 100% fΔT> MIC. Results and discussion: Characteristics of patients admission G1/G2 were: Clcr 115(90- 148)/127(90-170) ml/min; 30(24-31)/27(24-34) yrs, 70(61-75)/71(65-75) kg, 30(20- 42)/33.9(18-38.4)% total burn surface area, SAPS3 53(45-57)/48(37.8-59.5), medians (interquartile): thermal trauma occurred (17/16), electric trauma (1/2), inhalation injury (11/11), mechanical ventilation (9/16) and vasopressors required in 15/8 patients. It was demonstrated that different PK changes occurred for both beta-lactam agents after the extended or intermittent infusion by comparison with data reported in healthy volunteers. PK changes were related to the prolongation of biological half-life and increases on volume of distribution with impact on pharmacodynamics. On the other hand, meropenem total body clearance reduced by 50% at the earlier period of septic shock could be explained by the reduction of MER-transporters expression in the tubular renal secretion, once only patients with renal function preserved were included in the study protocol. Inflammatory biomarkers increased at the earlier period of septic shock: C-rp 232/183mg/L; leukocytes 11/14*103cel/mm3, neutrophils 9/10*103cel/mm3, medians, G1/G2. Clinical and microbiological cure was obtained for all patients of G1 against MIC < 2mg/L after intermittent 0.5 h infusion; while PK/PD target was attained for G2 patients undergoing antimicrobial therapy with MER or PTZ by extended infusion against gram negative strains K. pneumoniae, P. aeruginosa up to MIC 4mg L. Conclusion: Superiority of the extended infusion over intermitent infusion was obtained for the two antimicrobials was evidenced, in the therapeutic target considered 100%fΔT>CIM. Changes in the pharmacokinetics of these agents were recorded in patients compared to data reported for healthy volunteers. A significant difference between groups (G1/G2) was found in relation to biological half-life and volume of distribution for both piperacillin and meropenem


Subject(s)
Piperacillin/analysis , Burns/diagnosis , Meropenem/analysis , Patients/classification , Shock, Septic/complications , Pharmacokinetics , Pharmaceutical Preparations , Cross Infection/complications , Chromatography, Liquid/methods , Critical Illness/classification , Systemic Inflammatory Response Syndrome/diagnosis , Pharmacologic Actions , Enterobacteriaceae , Dosage , Intensive Care Units/classification , Anti-Infective Agents/analysis
10.
São Paulo; s.n; s.n; 2022. 93 p. tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1396684

ABSTRACT

O número de pessoas utilizando substâncias ilícitas de forma recreativa aumenta a cada ano, chamando a atenção de estudiosos de diversas áreas do conhecimento. Com isso, a demanda de exames toxicológicos exigida para trabalhadores, vítimas de crimes e esportistas também tem crescido. A amostra biológica mais utilizada para análises toxicológicas continua sendo a urina, visto que sua obtenção é menos invasiva, possibilita coletar grande volume de amostra e pode-se detectar substâncias até dias após ter ocorrido a exposição ou consumo. Entretanto, estas amostras necessitam de um grande volume físico para serem armazenadas e transportadas aos laboratórios, devendo ser mantidas em temperatura baixa e controlada para conservação. Outro ponto a se considerar é a quantidade de amostra insuficientemente coletada, ou extravasamento do conteúdo, contaminando outras amostras e muitas vezes, inviabilizando a análise. Uma alternativa recente para tais problemas é utilizar a técnica chamada de dried urine spots (DUS), onde poucos microlitros de urina são colocados em um papel absorvente e secos sob temperatura ambiente, preservando de agentes degradantes os componentes presentes na urina. Assim, o objetivo deste trabalho é avaliar a estabilidade das substâncias do presente estudo em alta temperatura, temperatura ambiente e em temperaturas de 4°C e -20°C. Para este fim, foi necessário desenvolver, validar e aplicar métodos de extração e determinação de anfetaminas e produtos de biotransformação de cocaína e tetraidrocanabinol carboxílico (THCCOOH) em amostras dried urine spot, utilizando cromatografia líquida acoplada à espectrometria de massas. Os picos foram identificados por UPLC-ESI-MS/MS, com tempo total de 5 mins utilizando fase A- água, formiato de amônio e 0,1% ácido fórmico, e B- metanol: acetonitrila (6:4) + 0,1% de ácido fórmico. A extração foi feita utilizando acetonitrila: metanol: acetona (1:1:1) +ácido fórmico 0,1%. Não foi possível iniciar a validação de THCCOOH, visto uma possível complexação do analito com o papel. Para as outras substâncias, o método cromatográfico desenvolvido se mostrou eficiente e seletivo, com LOD e LOQ de 10 ng/mL para todos os analitos, sendo linear até 1000 ng/mL, atendeu as especificações de precisão e exatidão e carryover. As amostras permaneceram estáveis ao longo de 32 dias nas temperaturas estudadas, demonstrando a segurança em se utilizar a técnica de DUS para armazenamento e transporte de amostras biológicas dentro da faixa de temperatura do estudo até 32 dias


The number of people using illegal substances in a recreational way increases each year, drawing the attention of scholars from different areas of knowledge. As a result, the demand for workplaces drug tests, toxicological tests for victims of crimes and dopping has also grown. The biological sample most used for toxicological tests remains urine, since obtaining it is less invasive, it is possible to collect a large volume of sample and it is possible to detect substances up to days after exposure or consumption has occurred. However, these samples require a large physical volume to be stored and transported to the laboratories, and must be kept at a low temperature for conservation. Another point to consider is the amount of sample insufficiently collected, or leakage of the content, causing contamination of other samples and often making the analysis unfeasible. A recent alternative to such problems is to use "dried urine spots" (DUS), where few microliters of urine are placed on absorbent paper and dried at room temperature, preserving the components present in the urine from degrading agents. Thus, the objective of this work is to evaluate the stability of the substances in this study at high temperature, room temperature and at temperatures of 4°C and -20°C. For this purpose, it was necessary to develop, validate and apply methods of extraction and determination of amphetamines and biotransformation products of cocaine and carboxylic tetrahydrocannabinol (THCCOOH) in dried urine spot samples, using liquid chromatography coupled to mass spectrometry (LC-MS). The peaks were identified liquid chromatography coupled to a mass spectrometer (UPLC-ESI-MS/MS), with a total time of 5 mins using phase A- water, ammonium formate and 0.1% formic acid, and B- methanol: acetonitrile (6:4) + 0.1% formic acid. Extraction was done using acetonitrile: methanol: acetone (1:1:1) + 0.1% formic acid. It was not possible to perform the validation of THCCOOH, given a possible complexation of the analyte with the paper. To the others substances, the chromatographic method developed proved to be efficient and selective, with LOD and LOQ of 10 ng/mL for all analytes, being linear up to 1000 ng/mL, meeting the specifications of precision and accuracy and carryover. The samples remained stable for 32 days at the temperatures studied, demonstrating the safety of using the DUS technique for storage and transport of biological samples until 32 days on temperature range studied


Subject(s)
Dronabinol/adverse effects , Biotransformation , Cocaine/adverse effects , Amphetamines/adverse effects , Mass Spectrometry/methods , Urine , Pharmaceutical Preparations/administration & dosage , Chromatography, Liquid/methods , Occupational Groups/classification
11.
São Paulo; s.n; s.n; 2022. 88 p. tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1390664

ABSTRACT

Planejamento de Experimentos (DoE) permite obter e explorar conhecimentos sobre inúmeros sistemas, facilitando a coleta de informações com reduzido número de experimentos. No entanto, DoE é restrito ao delineamento do desenho experimental. Para superar essa limitação e permitir uma previsão precisa dos tempos de retenção para uma seleção de filtros UV orgânicos sob diversas condições, usamos a Relação Quantitativa entre Estrutura e Retenção combinada com o método de Monte Carlo para desenvolver uma plataforma in silico capaz de prever o perfil cromatográfico de filtros UV orgânicos. Sete analitos foram usados para estabelecer o modelo de predição: benzofenona-3, avobenzona, ethilhexil triazona, octil dimetil PABA, metoxicinamato de octila, tinosorb® S e octocrileno. Os valores residuais obtidos no modelo de análise de regressão múltipla mostraram distribuição normal, homocedasticidade e independência. Os coeficientes de determinação (R2) e predição (R2 pred) foram de 99,82% e 99,71%, respectivamente. A plataforma in silico apresentou grande potencial para predição do perfil cromatográfico de filtros UV orgânicos, da coeluição de analitos, de seus parâmetros cromatográficos, além de permitir, sem experimentação, uma visão geral do comportamento de retenção de compostos sob diversas condições cromatográficas


Design of Experiments (DoE) allows obtaining and explorer knowledge about innumerous systems, facilitating the information collection with reduced number of experiments. However, DoE is restricted to the limited range which experimental design was delineated. In order to overcome this limitation and enable accurate prediction of retention times for a selection of organic UV filters under various conditions, we used the Quantitative Structure-Retention Relationships tool combined with Monte Carlo method to develop an in silico platform capable of predicting chromatographic profile of organic UV filters. Seven analytes were used to established to prediction model: benzophenone-3, butyl methoxydibenzoilmethane, ethylhexyl triazone, ethylhexyl dimetyl PABA, ethylhexyl methoxycinnamate, bisethylhexyloxyphenol methoxyphenyl triazine and octocrylene. Residual values obtained from multiple regression analysis model showed normal distribution, homoscedasticity, and independence. Determination (R2) and prediction (R2 pred) coefficients were found to be 99,82% and 99,71%, respectively. In silico platform presented great potential for predicting chromatographic profile of organic UV filters, analytes coelution, chromatographic parameters and allowing, without experimentation, an overview of retention behavior of compounds under various chromatographic conditions


Subject(s)
Sunscreening Agents , Regression Analysis , Chromatography, Liquid/methods , Planning , Methods , Filters , Monte Carlo Method
12.
São Paulo; s.n; s.n; 2022. 93 p. tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1392262

ABSTRACT

O número de pessoas utilizando substâncias ilícitas de forma recreativa aumenta a cada ano, chamando a atenção de estudiosos de diversas áreas do conhecimento. Com isso, a demanda de exames toxicológicos exigida para trabalhadores, vítimas de crimes e esportistas também tem crescido. A amostra biológica mais utilizada para análises toxicológicas continua sendo a urina, visto que sua obtenção é menos invasiva, possibilita coletar grande volume de amostra e pode-se detectar substâncias até dias após ter ocorrido a exposição ou consumo. Entretanto, estas amostras necessitam de um grande volume físico para serem armazenadas e transportadas aos laboratórios, devendo ser mantidas em temperatura baixa e controlada para conservação. Outro ponto a se considerar é a quantidade de amostra insuficientemente coletada, ou extravasamento do conteúdo, contaminando outras amostras e muitas vezes, inviabilizando a análise. Uma alternativa recente para tais problemas é utilizar a técnica chamada de dried urine spots (DUS), onde poucos microlitros de urina são colocados em um papel absorvente e secos sob temperatura ambiente, preservando de agentes degradantes os componentes presentes na urina. Assim, o objetivo deste trabalho é avaliar a estabilidade das substâncias do presente estudo em alta temperatura, temperatura ambiente e em temperaturas de 4°C e -20°C. Para este fim, foi necessário desenvolver, validar e aplicar métodos de extração e determinação de anfetaminas e produtos de biotransformação de cocaína e tetraidrocanabinol carboxílico (THCCOOH) em amostras dried urine spot, utilizando cromatografia líquida acoplada à espectrometria de massas. Os picos foram identificados por UPLC-ESI-MS/MS, com tempo total de 5 mins utilizando fase A- água, formiato de amônio e 0,1% ácido fórmico, e B- metanol: acetonitrila (6:4) + 0,1% de ácido fórmico. A extração foi feita utilizando acetonitrila: metanol: acetona (1:1:1) +ácido fórmico 0,1%. Não foi possível iniciar a validação de THCCOOH, visto uma possível complexação do analito com o papel. Para as outras substâncias, o método cromatográfico desenvolvido se mostrou eficiente e seletivo, com LOD e LOQ de 10 ng/mL para todos os analitos, sendo linear até 1000 ng/mL, atendeu as especificações de precisão e exatidão e carryover. As amostras permaneceram estáveis ao longo de 32 dias nas temperaturas estudadas, demonstrando a segurança em se utilizar a técnica de DUS para armazenamento e transporte de amostras biológicas dentro da faixa de temperatura do estudo até 32 dias


The number of people using illegal substances in a recreational way increases each year, drawing the attention of scholars from different areas of knowledge. As a result, the demand for workplaces drug tests, toxicological tests for victims of crimes and dopping has also grown. The biological sample most used for toxicological tests remains urine, since obtaining it is less invasive, it is possible to collect a large volume of sample and it is possible to detect substances up to days after exposure or consumption has occurred. However, these samples require a large physical volume to be stored and transported to the laboratories, and must be kept at a low temperature for conservation. Another point to consider is the amount of sample insufficiently collected, or leakage of the content, causing contamination of other samples and often making the analysis unfeasible. A recent alternative to such problems is to use "dried urine spots" (DUS), where few microliters of urine are placed on absorbent paper and dried at room temperature, preserving the components present in the urine from degrading agents. Thus, the objective of this work is to evaluate the stability of the substances in this study at high temperature, room temperature and at temperatures of 4°C and -20°C. For this purpose, it was necessary to develop, validate and apply methods of extraction and determination of amphetamines and biotransformation products of cocaine and carboxylic tetrahydrocannabinol (THCCOOH) in dried urine spot samples, using liquid chromatography coupled to mass spectrometry (LC-MS). The peaks were identified liquid chromatography coupled to a mass spectrometer (UPLC-ESI-MS/MS), with a total time of 5 mins using phase A- water, ammonium formate and 0.1% formic acid, and B- methanol: acetonitrile (6:4) + 0.1% formic acid. Extraction was done using acetonitrile: methanol: acetone (1:1:1) + 0.1% formic acid. It was not possible to perform the validation of THCCOOH, given a possible complexation of the analyte with the paper. To the others substances, the chromatographic method developed proved to be efficient and selective, with LOD and LOQ of 10 ng/mL for all analytes, being linear up to 1000 ng/mL, meeting the specifications of precision and accuracy and carryover. The samples remained stable for 32 days at the temperatures studied, demonstrating the safety of using the DUS technique for storage and transport of biological samples until 32 days on temperature range studied


Subject(s)
Dronabinol/adverse effects , Biotransformation , Cocaine/agonists , Amphetamines/analysis , Mass Spectrometry/methods , Urine/physiology , Chromatography, Liquid/methods
13.
Braz. J. Pharm. Sci. (Online) ; 58: e20686, 2022. tab, graf
Article in English | LILACS | ID: biblio-1420493

ABSTRACT

Abstract The objective of the present study is to develop and validate a simple, selective and accurate hydrophilic interaction liquid chromatography - a high performance liquid chromatography incorporating an evaporative light scattering detector (HILIC-HPLC-ELSD) method for simultaneously determining glucosamine hydrochloride and chondroitin sulfate in dietary supplements. The chromatographic separation was carried out on a ZIC-HILIC column (150 mm x 4.6 mm x 5µm) in isocratic system mode with a mobile phase of acetonitrile, 30 mM ammonium formate and water (77:20:3, v/v/v) at pH 4.5, a column temperature of 35°C, a flow rate of 1 mL.min-1, and an injection volume of 5 µL. An evaporative light scattering (ELS) detector was used. Effective separation was achieved by means of analyte resolution of more than 1.5 with an analysis run time of approximately 20 minutes. The linearity of glucosamine hydrochloride and chondroitin sulfate ranged from 0.4 to 2.5 mg.mL-1. The limits of the detection and quantification of glucosamine hydrochloride were 20 and 80 mg.mL-1 respectively, while for chondroitin sulfate they were 80 and 400 mg.mL-1. All validation parameters satisfied the acceptance criteria in accordance with International Conference on Harmonisation (ICH) guidelines. The method was successfully applied to the assay of commercial dietary supplement samples


Subject(s)
Chromatography, High Pressure Liquid/methods , Chromatography, Liquid/methods , Dietary Supplements/analysis , Validation Study , Glucosamine/agonists
14.
Braz. J. Pharm. Sci. (Online) ; 58: e18802, 2022. tab, graf
Article in English | LILACS | ID: biblio-1403736

ABSTRACT

Abstract The flavonoids and xanthones present in the ethanol extracts of leaves and stems of Fridericia samydoides showed that anti-dengue activities in vitro were investigated qualitatively by liquid chromatography-ultraviolet-mass spectrometry in series. Nineteen flavones and fifteen xanthones were detected and characterized on the basis of their fragmentation pattern in the positive and negative ion mode tandem mass spectrometry spectra and ultraviolet bands. Acacetin, chrysin, vitexin, isovitexin, orientin, isoorientin, mangiferin, 2'-O-trans-caffeoylmangiferin, 2'-O-trans-coumaroylmangiferin and 2'-O-trans-cinnamoylmangiferin were identified by comparison with authentic samples. The other compounds detected were tentatively assigned by analysis of the spectral data and by comparison with literature reports. In addition, it performed the fractionation of the leaves extract leading to the isolation of mangiferin, isovitexin and isoorientin. All extracts and isolated compounds inhibited the Dengue virus replication cycle with EC50 less than 25.0 µg/mL for extracts and 272.5, 85.6 and 79.3 µg/mL for mangiferin, isovitexin and isoorientin, respectively.


Subject(s)
Flavonoids/agonists , Bignoniaceae/adverse effects , Dengue Virus , Xanthones/agonists , Mass Spectrometry/methods , In Vitro Techniques/instrumentation , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods
15.
Braz. J. Pharm. Sci. (Online) ; 58: e191073, 2022. tab, graf
Article in English | LILACS | ID: biblio-1383972

ABSTRACT

Abstract Gabapentin is an antiepileptic drug prescribed for several neuropathic pain conditions. This study aimed to evaluate gabapentin (GAB) trough plasma concentration range and the applicability of therapeutic drug monitoring in patients with neuropathic pain. Fifty-three patients with neuropathic pain, aged 20 to 75, received gabapentin as treatment for at least 7 days. Gabapentin plasma concentration was sampled before GAB administration and quantified by liquid chromatography with a UV detector. GAB trough plasma concentration ranged between 0.40 and 11.94 µg/mL in patients with chronic neuropathic pain. No differences were observed in terms of GAB plasma concentrations between responsive and non-responsive patients. Our data suggest that the reference ranges suggested in the literature for patients with epilepsy should not be used for patients with neuropathic pain. Therapeutic drug monitoring of GAB was shown to be an important tool to assess treatment adherence.


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Patients/classification , Drug Monitoring/instrumentation , Gabapentin/analysis , Chromatography, Liquid/methods , Treatment Adherence and Compliance
16.
São Paulo; s.n; s.n; 2022. 166 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-1416533

ABSTRACT

O organogel é formado por uma matriz tridimensional composta de filamentos que se auto-organizam em uma rede entrelaçada e que, por seu tipo de estrutura, pode ser utilizado com o objetivo de atuar como um implante que se forma in situ, sendo capaz de se comportar como uma forma farmacêutica de liberação prolongada. Esse trabalho tem, por tanto, o objetivo desse trabalho foi desenvolver, caracterizar, quantificar e traçar perfis de dissolução para formulações de organogel contendo meloxicam como principio ativo. O material está dividido em quatro capítulos, sendo apresentada inicialmente (I) revisão da literatura a respeito da lecitina de origem vegetal, com suas principais fontes de obtenção, como soja, girassol e colza, e também seu uso farmacêutico na obtenção de formulações como organogéis, microemulsões e lipossomas. Os demais capítulos abordam (II) desenvolvimento e otimização de uma formulação de organogel contendo lecitina de soja e Pluronic® F-127 como formadores da matriz tridimensional e meloxicam como principio ativo. (III) Desenvolvimento e validação de um método de quantificação do teor de meloxicam por cromatografia líquida de alta eficiência (CLAE). (IV) Desenvolvimento de um método de dissolução para formulações de organogel, que fosse capaz de ser utilizado na caracterização do perfil de dissolução de diferentes formulações. Com os resultados obtidos, foi possível desenvolver formulações de organogel contendo lecitina de soja, Pluronic® F-127 e meloxicam, assim como um método analítico validado para as analises de teor. Por fim, foram obtidos também os perfis de dissolução de duas formulações mais promissoras


Organogels are formed by a three-dimensional matrix composed of filaments that selforganize in an interlaced network and that, due to its type of structure, can be used with the objective of acting as an implant that forms in situ, being able to behave as an extendedrelease dosage form. This work has, therefore, the objective of this work was to develop, characterize, quantify and trace dissolution profiles for organogel formulations containing meloxicam as active ingredient. The material is divided into four chapters, initially presented (I) review of the literature on lecithin of plant origin, with its main sources of production, such as soybean, sunflower and rapeseed, and also its pharmaceutical use in obtaining formulations such as organogels , microemulsions and liposomes. The remaining chapters address (II) development and optimization of an organogel formulation containing soy lecithin and Pluronic® F-127 as three-dimensional matrix formers and meloxicam as an active ingredient. (III) Development and validation of a method for quantification of meloxicam content by high performance liquid chromatography (HPLC). (IV) Development of a dissolution method for organogel formulations, capable of being used to characterize the dissolution profile of different formulations. With the results obtained, it was possible to develop organogel formulations containing soy lecithin, Pluronic® F-127 and meloxicam, as well as a validated analytical method for content analysis. Finally, the dissolution profiles of two more promising formulations were also obtained


Subject(s)
Pharmaceutical Preparations/analysis , Veterinarians , Veterinary Drugs/analysis , Poloxamer/analysis , Dissolution , Lecithins/analysis , Meloxicam/antagonists & inhibitors , Pharmacists/classification , Chemistry, Pharmaceutical/instrumentation , Chromatography, High Pressure Liquid/methods , Chromatography, Liquid/methods , Dosage Forms , Methods
17.
Journal of Forensic Medicine ; (6): 495-499, 2022.
Article in English | WPRIM | ID: wpr-984142

ABSTRACT

OBJECTIVES@#To analyze the characteristics of diphenidol poisoning cases and to provide clues and technical means for the identification of such cases.@*METHODS@#Biological samples of 9 deaths caused by diphenidol poisoning were detected by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and the characteristics of these cases were analyzed retrospectively.@*RESULTS@#Most of the deaths caused by diphenidol poisoning were young females. The dosage was between 60 and 300 tablets, and the mass concentration of diphenidol in the postmortem blood ranged from 0.87 to 99.00 μg/mL. There was no correlation between the dosage and the concentration of diphenidol in the blood.@*CONCLUSIONS@#Diphenidol poisoning has the characteristics of high concealment and lethality. More attention should be paid to suicide cases, and diphenidol should be recommended as a routine detection item to avoid missing detection.


Subject(s)
Female , Humans , Chromatography, Liquid/methods , Tandem Mass Spectrometry/methods , Retrospective Studies , Administration, Oral
18.
China Journal of Chinese Materia Medica ; (24): 1064-1072, 2022.
Article in Chinese | WPRIM | ID: wpr-928026

ABSTRACT

This study aims to establish a rapid and sensitive UPLC-MS/MS method for simultaneously determining the content of strychnine and paeoniflorin in plasma and brain tissue of rats, and compare the pharmacokinetic behavior and brain tissue distribution of paeoniflorin combined with normal and toxic doses of strychnine in rats after percutaneous administration. Compared with those in the toxic-dose strychnine group, the AUC_(0-t), AUC_(0-∞), and C_(max) of strychnine decreased by 51.51%, 45.68%, and 46.03%, respectively(P<0.01), and the corresponding values of paeoniflorin increased by 91.41%, 102.31%, and 169.32%, respectively(P<0.01), in the compatibility group. Compared with the normal-dose strychnine group, the compatibility group showed insignificantly decreased C_(max), AUC_(0-t), and AUC_(0-∞) of strychnine, increased C_(max) and T_(max) of paeoniflorin(P<0.01), 66.88% increase in AUC_(0-t), and 70.55% increase in AUC_(0-∞) of paeoniflorin. In addition, the brain tissue concentration of strychnine decreased and that of paeoniflorin increased after compatibility. The combination of paeoniflorin with normal dose and toxic dose of strychnine can inhibit the percutaneous absorption of strychnine, and greatly promote the percutaneous penetration of paeoniflorin, whereas the interaction mechanism remains to be explored. The UPLC-MS/MS method established in this study is easy to operate and has good precision. It is suitable for in vivo study of pharmacokinetic behavior and brain tissue distribution of paeoniflorin and strychnine after percutaneous administration in rats, which provides reference for the safe and rational clinical use of strychnine and the combined use of drugs, and lays a solid foundation for the development of external preparations containing Strychni Semen.


Subject(s)
Animals , Rats , Administration, Cutaneous , Brain , Bridged-Ring Compounds/pharmacology , Chromatography, Liquid/methods , Glucosides , Monoterpenes , Rats, Sprague-Dawley , Strychnine , Tandem Mass Spectrometry/methods , Tissue Distribution
19.
São Paulo; s.n; s.n; 2021. 96 p. tab, graf, ilus.
Thesis in Portuguese | LILACS | ID: biblio-1416965

ABSTRACT

Os cubossomos são partículas nanoestruturadas em forma de bicamada lipídica, bicontínuas e altamente curvadas, as quais devem ser estabilizadas por um polímero não-iônico, neste caso o Pluronic® F-127. Podem ser compostos por alguns tipos de lipídios específicos que possuem a capacidade de se auto associar em estruturas cúbicas quando estão em excesso de água, como o fitantriol (PHY) e a monoleína (GMO). Devido a sua estrutura única, cubossomos possuem um grande potencial para serem considerados como sistemas drug delivery. Os sistemas drug delivery são amplamente utilizados na pesquisa farmacêutica e em contextos clínicos para aumentar a eficácia de compostos utilizados para diagnóstico e de fármacos. No caso da cinarizina (CNZ), fármaco já aprovado para o tratamento de náuseas, vômitos e vertigens causadas pela doença de Ménière, existem inúmeros efeitos colaterais associados a sua baixa solubilidade. Desta forma, a encapsulação em cubossomos se torna uma abordagem promissora para resolver os problemas de atividade farmacológica relacionados ao fármaco. Neste trabalho, realizamos uma caracterização biofísica da interação da CNZ em cubossomos (contendo PHY ou myverol, MYV, sendo este composto por 80% de GMO). As técnicas biofísicas utilizadas foram: espalhamento de raios-X em baixos ângulos (SAXS), espalhamento dinâmico de luz (DLS), microscopia eletrônica de transmissão (TEM), crio microscopia eletrônica de transmissão (Crio-TEM), análise de rastreamento de nanopartículas (NTA) e potencial zeta. A cromatografia líquida de alta eficiência (HPLC) foi realizada para verificar a porcentagem de eficiência de encapsulação (%EE) da CNZ nos cubossomos, enquanto que a citotoxicidade foi avaliada em eritrócitos através da análise da atividade hemolítica. Inicialmente, a influência de diferentes solventes (acetona, clorofórmio, etanol e octano) nas propriedades estruturais de cubossomos de PHY foi investigada, a fim de se minimizar os efeitos do solvente utilizados para a encapsulação da CNZ. Para amostras com acetona, descobriu-se que apenas altas concentrações tiveram influência na estrutura cristalográfica das nanopartículas, sendo o resultado foi totalmente reversível após 24h. O etanol fez com que o parâmetro de rede aumentasse de 10-15%. O clorofórmio e o octano tiveram efeitos diferentes sobre cubossomos de PHY em comparação com a acetona e o etanol; ambos induziram uma transição cúbico-hexagonal-micelar. Posteriormente, constatamos que as nanopartículas de PHY e MYV apresentaram diferentes estruturas cristalográficas, sendo elas Pn3m e Im3m, respectivamente. Devido a problemas com a baixa solubilidade de CNZ em PHY os estudos para esse lipídio foram suspensos. Nos testes para cubossomos de MYV ao incorporar a CNZ foi observado uma alteração da estrutura cúbica de Im3m para Pn3m e os valores dos parâmetros de rede se alteraram de acordo com a estrutura cristalina encontrada, porém os valores não apresentaram diferenças significativas de tamanho quando se trata da mesma estrutura, sugerindo que a CNZ não interferiu no parâmetro de rede. Os tamanhos das nanopartículas apresentaram uma população monodispersa com ~200 nm. DLS mostrou uma interferência da CNZ no tamanho dos cubossomos, variando de forma diretamente proporcional a concentração de CNZ na amostra, enquanto as técnicas de NTA e microscopia apresentaram nanopartículas de tamanhos bastante variados, mas independente da interferência da CNZ. A encapsulação de CNZ também foi dosada por HLPC em cubossomos de MYV, obtendo um limite superior de 0,6 mg/mL. A atividade citotóxica dos cubossomos foi testada em eritrócitos, revelando uma taxa de hemólise bastante inferior em cubossomos com CNZ em relação a cubossomos puros. Acreditamos que os cubossomos podem sim ser utilizados como sistemas carreadores de CNZ


Cubosomes are nanostructured particles in the form of a lipid bilayer, bicontinuous and highly curved, which must be stabilized by a non-ionic polymer, in this case Pluronic® F-127. They can be composed of some types of specific lipids that have the ability to self-associate in cubic structures when they are in excess of water, such as phytantriol (PHY) and monolein (GMO). Due to their unique structure, cubosomes have a great potential to be considered as drug delivery systems. Drug delivery systems are widely used in pharmaceutical research and clinical settings to increase the efficacy of compounds used for diagnostics and drugs. In the case of cinnarizine (CNZ), a drug already approved for the treatment of nausea, vomiting and vertigo caused by Ménière's disease, there are numerous side effects associated with its low solubility. Thus, cubosomal encapsulation becomes a promising approach to solve drug-related problems of pharmacological activity. In this work, we performed a biophysical characterization of the CNZ interaction in cubosomes (containing PHY or myverol, MYV, which is composed of 80% GMO). The biophysical techniques used were: low angle X-ray scattering (SAXS), dynamic light scattering (DLS), transmission electron microscopy (TEM), cryo transmission electron microscopy (Crio-TEM), nanoparticle tracking analysis (NTA) and zeta potential. High performance liquid chromatography (HPLC) was performed to verify the percentage of encapsulation efficiency (%EE) of CNZ in cubosomes, while cytotoxicity was evaluated in erythrocytes by analyzing the hemolytic activity. Initially, the influence of different solvents (acetone, chloroform, ethanol and octane) on the structural properties of PHY cubosomes was investigated in order to minimize the effects of the solvent used for the encapsulation of CNZ. For samples with acetone, it was found that only high concentrations had an influence on the crystallographic structure of the nanoparticles, with the result being fully reversible after 24h. Ethanol caused the network parameter to increase by 10-15%. Chloroform and octane had different effects on PHY cubosomes compared to acetone and ethanol; both induced a cubic-hexagonal-micellar transition. Later, we found that PHY and MYV nanoparticles presented different crystallographic structures, being Pn3m and Im3m, respectively. Due to problems with the low solubility of CNZ in PHY, studies for this lipid were suspended. In the tests for MYV cubosomes when incorporating CNZ, a change in the cubic structure from Im3m to Pn3m was observed and t he lattice parameters changed according to the crystal structure found, but the differences observed were not significant when it comes to the same structure, suggesting that the CNZ did not interfere with the network parameter. The nanoparticle sizes showed a monodisperse population with ~200 nm. DLS showed an interference of CNZ in the size of the cubosomes, varying directly proportionally to the concentration of CNZ in the sample, while NTA and microscopy techniques showed nanoparticles of widely varying sizes, but independent of CNZ interference. CNZ encapsulation was also dosed by HLPC in MYV cubosomes, obtaining an upper limit of 0.6 mg/ml. The cytotoxic activity of cubosomes was tested in erythrocytes, revealing a much lower rate of hemolysis in cubosomes with CNZ compared to pure cubosomes. We believe that cubosomes can indeed be used as CNZ carrier systems


Subject(s)
Cinnarizine/analysis , Efficiency , Acetone/agonists , Chromatography, High Pressure Liquid/methods , Chromatography, Liquid/methods , Microscopy, Electron, Transmission/instrumentation , Nanoparticles/adverse effects , Dynamic Light Scattering/instrumentation , Pharmaceutical Research , Lipid Bilayers/pharmacology , Meniere Disease/pathology
20.
São Paulo; s.n; s.n; 2021. 110 p. tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1379145

ABSTRACT

Introdução: O Meropenem é um carbapenêmico de amplo espectro, prescrito na terapia do choque séptico nos pacientes graves adultos de UTI, com infecções graves causadas por patógenos Gram-negativos susceptíveis. Objetivo: Avaliar a efetividade do Meropenem em pacientes sépticos queimados, investigar a farmacocinética na fase precoce e na fase tardia durante o curso do choque séptico e o impacto no desfecho clínico. Ética, Casuística e Procedimentos: Aprovação ética, registro CAAE07525118.3.0000.0068; nenhum conflito de interesse declarado foi obtido dos autores. Após assinatura do TCLE pelo responsável legal, o paciente foi incluído no protocolo. Investigou-se a população de 15 pacientes sépticos grandes queimados, adultos de ambos os gêneros (10 M/ 5F) com função renal preservada (Clcr> 50 ml/min). As características demográficas da população de pacientes incluídos foram idade de 37(33 -41) anos, 71(59,5 - 80,0) kg e índice de massa corpórea de 24,3(20,6-24,7) kg/m2, medianas (interquartil). Registrou-se o escore SAPS*3 54(47-59) de admissão dos pacientes na UTI; a superfície corpórea total queimada foi de 33% (18,3-34,4), SCTQ medianas (interquartil). A lesão inalatória e o uso de vasopressores foram registrados em 12/15 pacientes após trauma térmico/ elétrico (10/5). Após intubação orotraqueal, a ventilação mecânica foi registrada em 13/15 pacientes. A terapia empírica do choque séptico com Meropenem no regime de 1g q8h, por infusão estendida de 3 horas, foi iniciada após a coleta das culturas. Realizou-se coleta seriada de amostras sanguíneas para dosagem sérica do antimicrobiano por cromatografia líquida. Aplicou-se o modelo aberto monocompartimental para estudo da farmacocinética e estimativa dos parâmetros, meia vida biológica, depuração total corporal e volume de distribuição. A abordagem farmacocinética-farmacodinâmica (PK-PD) foi baseada na dosagem sérica do Meropenem e na taxa de eliminação, para estimativa do índice de predição de efetividade (% ƒ Δ?T> CIM), considerando o novo alvo terapêutico de 100% ƒ Δ?T> CIM. Utilizou-se estatística não paramétrica pela aplicação do teste de Wilcoxon para dados pareados e testes de correlação linear. Resultados e Discussão: Registrou-se alteração dos parâmetros farmacocinéticos nos pacientes sépticos investigados frente aos dados reportados para voluntários sadios. Evidenciou-se redução na taxa de eliminação e da depuração total corporal; o prolongamento da meia vida biológica ocorreu pelo aumento do volume de distribuição. Estas alterações impactaram estendendo a cobertura do Meropenem, na fase precoce do choque séptico, contra os patógenos de susceptibilidade intermediária com CIM 4 mg/L. Conclusão: A cobertura do Meropenem foi garantida contra os patógenos isolados até CIM 2 mg/L para todos os pacientes. Adicionalmente, ocorreu a erradicação de patógenos de susceptibilidade intermediária CIM 4 mg/L, pela cobertura que foi atingida apenas na fase precoce do choque séptico. Então, a abordagem PK / PD contribui para a obtenção do resultado


Background: Meropenem is a carbapenêmic, agent largely prescribed to septic patients in the Intensive Care Units with severe infections caused by Gram-negative susceptible strains. Objective: To evaluate Meropenem effectiveness in ICU septic burn patients and to investigate pharmacokinetic changes that could impact the desired outcome by eradication of Gram-negative strains of intermediate susceptibility. Ethics, Casuistry and Methods: Ethical approval register CAEE 07525118.3.0000.0068was obtained; no conflicts of interest to declare were obtained from all authors. Fifteen burn adult patients of both genders (10 M/ 5F) with preserved renal function (Clcr> 50 ml/min) were investigated after TCLE signed. Demographic characteristics of patients included were: 37(33 -41) years, 71(59.5- 80.0) kg, 24.3 (20.6-24.7) kg/m2 body mass index, medians (quartiles). ICU patients admission was based on SAPS*3 score of 54(47-59), 33% (18.3-34.4) TBSA medians (quartiles). Inhalation injury and vasopressors requirements were in 12/15 patients after fire/electricity (10/5, proportion). Mechanical ventilation was necessary in 13/15 patients. Antimicrobial therapy of septic shock with meropenem 1g q8h 3 hours infusion started, after cultures collection. A serial of blood samples was collected from the central catheter after a minimum of 48 hours of Meropenem therapy for drug serum measurements by liquid chromatography. One compartment open model was applied to estimate PK data related to the elimination rate constant, biological half-life, total body clearance and volume of distribution PK/PD approach was based on serum trough levels and elimination rate constant to estimate the predictive index of drug effectiveness (% fΔT>CIM), based on the new PK/PD target 100% fΔT>CIM. Non parametric statistics was applied, Wilcoxon test for paired data and linear correlations. Results: Pharmacokinetic changes occurred in septic burn patients investigated by comparison with results reported in healthy volunteers as follows by the reduction on elimination rate constant and also on total body clearance, in spite of preserved renal function for all patients included. In addition, a prolongation of biological half-life occurred as a consequence of increases on volume of distribution. Pharmacodynamics was impacted by PK changes only at the earlier period of septic shock, once pathogens isolated of intermediate susceptibility up to MIC 4 mg/L were eradicated. Conclusion: Meropenem effectiveness was guaranteed against Gram-negative up to MIC 2 mg/L strains isolated for all patients. In addition, eradication of pathogens of intermediate susceptibility MIC 4 mg/L strains occurred only at the earlier period of septic shock. Then, PK/PD approach contributes to desired outcome achievement


Subject(s)
Humans , Male , Female , Adult , Patients , Wounds and Injuries/drug therapy , Burns/pathology , Pharmacokinetics , Meropenem/analysis , Shock, Septic/complications , Pharmaceutical Preparations/administration & dosage , Inhalation , Chromatography, Liquid/methods , Pharmacologic Actions , Intensive Care Units/classification
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