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1.
Bioanalysis ; 16(8): 249-278, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38466891

RESUMO

Aim: In this study, we evaluated the greenness and whiteness scores for microextraction techniques used in therapeutic drug monitoring. Additionally, the cons and pros of each evaluated method and their impacts on the provided scores are also discussed. Materials & methods: The Analytical Greenness Sample Preparation metric tool and white analytical chemistry principles are used for related published works (2007-2023). Results & conclusion: This study provided valuable insights for developing methods based on microextraction techniques with a balance in greenness and whiteness areas. Some methods based on a specific technique recorded higher scores, making them suitable candidates as green analytical approaches, and some others achieved high scores both in green and white areas with a satisfactory balance between principles.


[Box: see text].


Assuntos
Monitoramento de Medicamentos , Química Verde , Microextração em Fase Líquida , Microextração em Fase Sólida , Monitoramento de Medicamentos/métodos , Microextração em Fase Sólida/métodos , Microextração em Fase Líquida/métodos , Humanos , Preparações Farmacêuticas/análise
2.
Sci Rep ; 13(1): 16174, 2023 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-37758789

RESUMO

The increasing population of diabetic patients, especially in developing countries, has posed a serious risk to the health sector, so that the lack of timely diagnosis and treatment process of diabetes can lead to threatening complications for the human lifestyle. Here, a multiple sensor was fabricated on a paper substrate for rapid detection and controlling the progress of the diabetes disease. The proposed sensor utilized the sensing ability of porphyrazines, pH-sensitive dyes and silver nanoparticles in order to detect the differences in saliva composition of diabetic and non-diabetic patients. A unique color map (sensor response) was obtained for each studied group, which can be monitored by a scanner. Moreover, a good correlation was observed between the colorimetric response resulting from the analysis of salivary composition and the fasting blood glucose (FBG) value measured by standard laboratory instruments. It was also possible to classify participants into two groups, including patients caused by diabetes and those were non-diabetic persons with a total accuracy of 88.9%. Statistical evaluations show that the multiple sensor can be employed as an effective and non-invasive device for continuous monitoring of diabetes, substantially in the elderly.


Assuntos
Diabetes Mellitus , Nanopartículas Metálicas , Humanos , Idoso , Saliva/química , Colorimetria/métodos , Prata/análise , Diabetes Mellitus/diagnóstico
3.
J Chromatogr Sci ; 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37534561

RESUMO

Histamine as an important biogenic amino acid was measured in tuna fish samples by ultra-performance liquid chromatography using a phenyl isothiocyanate derivative. Minitab software was used to design the experiment and investigate the effective factors during the process, which includes screening and optimization steps. A partial factorial design was used in the screening stage and a central composite design was used in the optimization. Effective parameters in histamine derivatized were examined in the screening step including triethylamine volume, phenyl isothiocyanate volume, reaction temperature, reaction time and mobile phase pH. Then, in the optimization, effective parameters were identified and finally, the calibration curve was drawn from a concentration of 0.5-10.0 µg.mL-1 for histamine derivatized and a correlation coefficient of 0.994 was obtained for histamine derivatized. The method detection limit was 0.36 µg.mL-1 and the limit of quantification (LOQ) was 1.19 µg.mL-1. The relative standard deviation of the method was obtained for concentrations of 1.0-100.0 µg.mL-1 in the range between 1.06 and 2.21%. The recovery method was obtained from 90.8 to 103.1% for measuring histamine derivatized in real fish samples.

4.
Chem Zvesti ; 77(2): 619-655, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36213319

RESUMO

Molecular imprinted polymers (MIPs) as extraordinary compounds with unique features have presented a wide range of applications and benefits to researchers. In particular when used as a sorbent in sample preparation methods for the analysis of biological samples and complex matrices. Its application in the extraction of medicinal species has attracted much attention and a growing interest. This review focus on articles and research that deals with the application of MIPs in the analysis of components such as biomarkers, drugs, hormones, blockers and inhibitors, especially in biological matrices. The studies based on MIP applications in bioanalysis and the deployment of MIPs in high-throughput settings and optimization of extraction methods are presented. A review of more than 200 articles and research works clearly shows that the superiority of MIP techniques lies in high accuracy, reproducibility, sensitivity, speed and cost effectiveness which make them suitable for clinical usage. Furthermore, this review present MIP-based extraction techniques and MIP-biosensors which are categorized on their classes based on common properties of target components. Extraction methods, studied sample matrices, target analytes, analytical techniques and their results for each study are described. Investigations indicate satisfactory results using MIP-based bioanalysis. According to the increasing number of studies on method development over the last decade, the use of MIPs in bioanalysis is growing and will further expand the scope of MIP applications for less studied samples and analytes.

5.
Mikrochim Acta ; 189(7): 255, 2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35697898

RESUMO

Over recent years, great efforts have been extensively documented in top scientific journals on the development of methods for early diagnosis, treatment, and monitoring of cancers which are prevalent critical diseases with a high mortality rate among men and women. The determination of cancer biomarkers using different optimum methodologies is one of the finest options for achieving these goals with more precision, speed, and at a lower cost than traditional clinical procedures. In this regard, while focusing on specific biomarkers, molecularly imprinted technology has enabled novel diagnostic techniques for a variety of diseases. Due to the well-known advantages of molecularly imprinted polymers (MIPs), this review focuses on the current trends of MIPs-based extraction/microextraction methods, specifically targeting cancer biomarkers from various matrices. These optimized methods have demonstrated high selectivity, accuracy, sorbent reusability, extraction recovery, and low limits of detection and quantification for a variety of cancer biomarkers, which are a powerful tool to provide early diagnosis, prognosis, and treatment monitoring, with potential clinical application expected soon. This review highlights the key progress, specific modifications, and strategies used for MIP synthesis. The future perspectives for cancer biomarkers purification and determination by fabricating MIP-based techniques are also discussed.


Assuntos
Impressão Molecular , Neoplasias , Biomarcadores Tumorais , Feminino , Humanos , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Neoplasias/diagnóstico , Polímeros
6.
Biomed Chromatogr ; 35(7): e5105, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33660303

RESUMO

Analysis of biological samples is affected by interfering substances with chemical properties similar to those of the target analytes, such as drugs. Biological samples such as whole blood, plasma, serum, urine and saliva must be properly processed for separation, purification, enrichment and chemical modification to meet the requirements of the analytical instruments. This causes the sample preparation stage to be of undeniable importance in the analysis of such samples through methods such as microextraction techniques. The scope of this review will cover a comprehensive summary of available literature data on microextraction techniques playing a key role for analytical purposes, methods of their implementation in common biological samples, and finally, the most recent examples of application of microextraction techniques in preconcentration of analytes from urine, blood and saliva samples. The objectives and merits of each microextration technique are carefully described in detail with respect to the nature of the biological samples. This review presents the most recent and innovative work published on microextraction application in common biological samples, mostly focused on original studies reported from 2017 to date. The main sections of this review comprise an introduction to the microextraction techniques supported by recent application studies involving quantitative and qualitative results and summaries of the most significant, recently published applications of microextracion methods in biological samples. This article considers recent applications of several microextraction techniques in the field of sample preparation for biological samples including urine, blood and saliva, with consideration for extraction techniques, sample preparation and instrumental detection systems.


Assuntos
Métodos Analíticos de Preparação de Amostras , Microextração em Fase Líquida , Microextração em Fase Sólida , Animais , Biomarcadores/análise , Humanos , Ratos , Manejo de Espécimes
7.
Biomed Chromatogr ; 27(11): 1481-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23832864

RESUMO

This study presents the use of molecularly imprinted polymer (MIP) as packing material for microextraction by packed syringe (MEPS) to achieve higher extraction selectivity. Pentycaine was used as template for MIP. Development and validation of the determination of lidocaine, ropivacaine, mepivacaine and bupivacaine in human plasma and urine samples utilizing MIP-MEPS and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were carried out. The MEPS MIP-cartridge could be used for 100 extractions before it was discarded. The extraction recovery ranged from 60 to 80%. The correlation coefficients values were >0.999 for all assays using lidocaine, ropivacaine, mepivacaine and bupivacaine in the calibration range 5-2000 nmol/L. The accuracy of the studied compounds, given as a percentage variation from the nominal concentration values, ranged from -4.9 to 8.4% using plasma and urine samples. The between-batch precision, given as the relative standard deviation, at three different concentrations (quality control samples) was ranged from -4.7 to 14.0% and from 1.8 to 12.7% in plasma and urine, respectively. The lower limit of quantification and limit of detection of the studied substances were 5.0 and 1.0 nm, respectively.


Assuntos
Anestésicos Locais/sangue , Anestésicos Locais/urina , Cromatografia Líquida/métodos , Impressão Molecular , Espectrometria de Massas em Tandem/métodos , Amidas/sangue , Amidas/isolamento & purificação , Amidas/urina , Anestésicos Locais/isolamento & purificação , Bupivacaína/sangue , Bupivacaína/isolamento & purificação , Bupivacaína/urina , Humanos , Lidocaína/sangue , Lidocaína/isolamento & purificação , Lidocaína/urina , Limite de Detecção , Mepivacaína/sangue , Mepivacaína/isolamento & purificação , Mepivacaína/urina , Polímeros/química , Ropivacaina
8.
Artigo em Inglês | MEDLINE | ID: mdl-23353810

RESUMO

Ultrasound-assisted emulsification microextraction (USAE-ME) procedure coupled with UV-vis spectrophotometric measurement has been developed for determination of thiocyanate ion (SCN(-)) in water and biological fluids samples. The method is based on protonation of SCN(-) ions in acidic medium and extraction of thiocyanic acid into fine droplets of chloroform as an extraction solvent contains rhodamine B (RhB). The RhB was protonated in presence of thiocynanic acid to form highly colored ion-pair complex of [thiocynate][RhBH(+)] in chloroform, which used for subsequent spectrophotometric determination of SCN(-) ions. Experimental parameters for both spectrophotometric reaction and USAE-ME procedure have been optimized. Under optimized conditions the calibration curve for SCN(-) showed good linearity in the range of 38.0-870.0ngmL(-1) (R(2)=0.9967). The limit of detection (S/N=3) and preconcentration factor were 5.0ngmL(-1) and 40, respectively. Relative standard deviation for determination of 200ngmL(-1) of SCN(-) was 2.8% (n=5). The proposed method has been successfully applied for determination of SCN(-) ion in tap water, mineral bottled water and human saliva and urine samples with an average recovery of 99.2%.


Assuntos
Fracionamento Químico/métodos , Saliva/química , Sonicação/métodos , Tiocianatos/análise , Tiocianatos/urina , Adulto , Centrifugação , Clorofórmio/química , Água Potável/química , Humanos , Limite de Detecção , Modelos Lineares , Masculino , Reprodutibilidade dos Testes , Rodaminas/química , Fumar/metabolismo , Fumar/urina , Cloreto de Sódio/química , Espectrofotometria Ultravioleta , Ácidos Sulfúricos/química , Tiocianatos/química
9.
Artigo em Inglês | MEDLINE | ID: mdl-22446766

RESUMO

Ultrasound-assisted cloud point extraction (UACPE) procedure was developed for speciation and indirect spectrophotometric determination of chromium(III) and (VI) in environmental water samples. The method is based on the reduction of Cr(VI) by iodide in acidic media and subsequently formation of I(3)(-) anion. The I(3)(-) formed can further react with cetyltrimethylammonium bromide (CTAB) and induce its clouding due to formation of an ion-association complex. The formed complex was separated from solution and dissolved in ethanol for spectrophotometric measurement. Cerium(IV) ammonium sulphate was chosen as an oxidizing reagent for pre-oxidation step of Cr(III) to Cr(VI) species before the addition of iodide to the system, up to chromium in trivalent can be determined by the procedure. Experimental parameters for both spectrophotometric reaction and extraction procedure have been optimized. Under optimized conditions Cr(VI) can be determined in the range 20-400 ng mL(-1) (R(2)=0.999). Detection limit, preconcentration factor and relative standard deviation were 12 ng mL(-1), 20.0 and 2.2% (n=5), respectively with 10 mL sample volumes. The proposed method has been successfully applied for determination of chromium(V) in spiked water, synthetic seawater and electroplating wastewater samples with average recoveries of 100.1, 99.4 and 99.1%, respectively.


Assuntos
Fracionamento Químico/métodos , Cromo/isolamento & purificação , Espectrofotometria/métodos , Poluentes Químicos da Água/isolamento & purificação , Água/análise , Cetrimônio , Compostos de Cetrimônio/química , Cromo/análise , Limite de Detecção , Oxirredução , Ultrassom/métodos , Poluentes Químicos da Água/análise
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