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1.
Artigo em Inglês | MEDLINE | ID: mdl-38781478

RESUMO

Dietary supplements are drastically growing as a category of consumer products all over the world. The abuse of supplements marketed for slimming purposes and physical fitness has been observed worldwide in recent years, which raises concerns in terms of public health. In this study, different types of dietary supplements marketed and delivered through the e-commerce were studied for the determination of thallium as a hazardous inorganic contaminant. The total content of thallium was determined by a sensitive voltammetric method after a microwave-assisted oxidative digestion of the sample. In addition, a comparative spectrometric method was applied for validation of the results in the samples. The maximum concentration found for thallium was found to be 2.89 mg kg-1, which well agree with the comparative measurement. Considering the 32 studied formulations, it can be pointed out that ∼24% of the of dietary supplements presented Tl concentrations at concentrations higher than 1 mg kg-1. The results permitted the assessment of the health risk related to thallium from contaminated samples, based on the calculation of the estimated daily intake (EDI) and the risk quotient (HQ). The highest daily intake of thallium was calculated as 82.0 µg day-1 in a protein-based supplement, which is equivalent to an EDI of 1.17 µg kg-1 day-1. This work highlights the need to develop regulations on the limits of toxic elements such as thallium in widely consumed dietary supplements, as well as an in-depth look at the adverse effects caused by this element in the human body.


Assuntos
Suplementos Nutricionais , Contaminação de Alimentos , Tálio , Redução de Peso , Tálio/análise , Suplementos Nutricionais/análise , Humanos , Contaminação de Alimentos/análise
2.
Talanta ; 197: 20-27, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30771924

RESUMO

New guidelines for the limits of elemental impurities in drug products were introduced by the International Council for Harmonization in 2014. While the guidelines define a limit for each element, the complete quantification of the 24 elements included is, in fact, unnecessary. An accurate "pass/fail" test to determine whether the threshold was exceeded or not could be valuable in this context. In this study, a screening procedure using the features of high-resolution continuum source graphite furnace atomic absorption spectrometry for the evaluation of 12 elements in three different drugs was developed. The three-dimensional absorbance spectrum including time and wavelength in the vicinity of the main line of the element allows for a pass/fail decision related to the presence or absence of the element in the sample. Additionally, the bi-dimensional absorbance-wavelength spectrum defines the elements captured in the window when additional peaks are seen in the spectrum. The analysis of the selected drugs included sample digestion, the definition of pyrolysis and atomization temperatures, determination of the limit of detection and other validation parameters for each element. The evaluation of the spectra, both three- and bi-dimensional, revealed that only three elements, Cr, Ni, and Cu, were present in the samples in amounts above the LOD and therefore "fail" in the test. Nevertheless, they were quantified, and the analysis revealed that their levels were below the permitted daily exposure, which are at least 6 times higher than the LOD of the selected elements. Operating in a routine mode, the proposed method is a good option for the evaluation of elemental impurities in drug active ingredients or drug final products.


Assuntos
Grafite/química , Losartan/química , Metais Pesados/análise , Omeprazol/química , Sinvastatina/química , Espectrofotometria Atômica
3.
J Pediatr Gastroenterol Nutr ; 67(5): 671-676, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29985872

RESUMO

BACKGROUND AND OBJECTIVES: Parenteral nutrition (PN) administered to newborns (NB) may be contaminated with polycyclic aromatic hydrocarbons (PAHs) and may therefore increase the contact with these toxicants in very early life stages. The aim of the study is to determine to what extent, if any, commercial products for PN are contaminated with PAHs and to determine whether these contaminants, when present in the bag content, are delivered to NB and whether 1-hydroxypyrene (1-HP), the pyrene metabolite, can be detected in the urine of exposed NB. METHODS: Commercial products and the bags administered to 10 NB during their period in the NICU were analyzed for the 16 priority US Environmental Protection Agency PAHs. Urine samples were collected and analyzed for their 1-HP content. Urine samples of a control group composed of 8 breastfed NB were also analyzed for the determination of 1-HP. RESULTS: From 9 different commercial products used to compound PN bags, 6 were contaminated with PAHs, with total concentrations varying from 0.02 to 10.56 mg/L. In the bags administered to the NB, this sum varied from 0.01 to 6.30 mg/L with a mean of 2.62 mg/L. Therefore, for each 100 mL PN, an average load of 0.26 mg PAHs was observed. The majority of the urine samples taken from NB in the study group (80%) contained 1-HP, but it was not detected in the urine of any baby in the control group. CONCLUSIONS: The contamination of PN with PAHs poses a critical toxicological risk. The elevated contaminant concentrations and the parenteral way of administration make this source of PAHs considerably worse than any other, including maternal exposure to environmental pollution or tobacco.


Assuntos
Exposição Dietética/análise , Contaminação de Alimentos/análise , Nutrição Parenteral/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Pediátrica , Masculino , Pirenos/urina
4.
J Pharm Anal ; 8(6): 366-372, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30595942

RESUMO

Caffeine is present in products marketed for weight loss, with the purpose of increasing thermogenesis and lipid metabolism. The dosage declared by the product manufacturer, or even its presence, is not always correctly described on the label. This work aimed to investigate the undeclared synthetic caffeine in weight loss formulations by a high-performance liquid chromatography with diode array detection (HPLC-DAD) method. From one hundred products purchased through Brazilian e-commerce, seventeen contained caffeine, either naturally or synthetically added to formulation. The caffeine-containing samples were confirmed by an ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method, and adulteration was clearly proven in five products. The content highest caffeine contained 448.8 mg per dose. Other irregularities were also found; nevertheless, the most serious was the addition of synthetic drugs without asking the consumers. Additional drugs expose the consumer to more possible side-effects as well as deleterious drug interactions. Intentional adulteration with any unlabeled substance is typically motivated by a desire to increase or alter the claimed effect of the marketed product to gain a commercial advantage.

5.
Rev. bras. farmacogn ; 27(4): 426-433, July-Aug. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-898683

RESUMO

ABSTRACT The phenolic content of the medicinal species Connarus perrottetti var. angustifolius Radlk., Connaraceae, Cecropia obtuse Trécul, Cecropia palmata Willd., Urticaceae; and Mansoa alliacea (Lam.) A.H.Gentry, Bignoniaceae, collected in three different years was evaluated. Plant infusions and hydroalcoholic, butanol and ethyl acetate extracts were analyzed by high-performance liquid chromatography with diode array detection. In order to endorse these results, analysis by electrospray mass spectrometry was also performed. Were identified: gallic acid, catechin, caffeic acid, ferulic acid, rutin, quercitrin and resveratrol. C. perrottetti showed greater diversity of polyphenols. M. alliacea had the higher concentration of caffeic acid even though it was found in all species. Catechin was the major antioxidant, but was not detected in M. alliacea. However, we discuss the popular use of these species, as well as their phenolic constitution and the interannual distribution of phenolic compounds.

6.
J AOAC Int ; 100(4): 1070-1076, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28720176

RESUMO

HPLC coupled to UV diode array detection (DAD) is proposed for the determination of polycyclic aromatic hydrocarbons (PAHs) in pharmaceutical products for parenteral administration. Because rubber is a possible source of PAHs for these products, samples stored in containers with rubber parts were selected for the analysis. The basis for method optimization was EPA Method 8310, which determines 16 priority PAHs in ground water and wastewater by HPLC using both UV and fluorescence detection. Using DAD, two channels were selected for detection, with one operating at 254 nm for the detection of nine PAHs and the other at 225 nm for the detection of seven PAHs. This method allowed for the detection of PAHs using external calibration with LODs and LOQs ranging from 0.001 to 0.060 µg/mL and from 0.003 to 0.167 µg/mL, respectively. Within-day precision, expressed as RSD, varied from 1.24 to 7.76% for PAH concentrations from 0.05 to 0.50 µg/mL, and intraday precision varied from 3.10 to 9.40% for the same concentration range. Method accuracy was confirmed by recoveries of 75-120% of the spiked samples. This method was applied for the determination of PAHs in three commercial infusion solutions and in nine different medications stored in syringes prior to administration to patients. Twelve of 16 PAHs were found in these samples. Total PAH concentrations varied from 0.13 to 13.50 µg/mL. Pyrene was the most prevalent contaminant, being present in 11 of 12 samples in concentrations ranging from 0.17 to 4.80 µg/mL. This method presented good sensitivity for the measurement of PAH in the target samples, allowing for the determination of the 16 priority PAHs in one run and in 30 min.


Assuntos
Contaminação de Medicamentos , Soluções de Nutrição Parenteral/análise , Preparações Farmacêuticas/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Calibragem , Cromatografia Líquida de Alta Pressão , Limite de Detecção
7.
J AOAC Int ; 2017 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-28330525

RESUMO

HPLC coupled to UV diode array detection (DAD) is proposed for the determination of polycyclic aromatic hydrocarbons (PAHs) in pharmaceutical products for parenteral administration. Because rubber is a possible source of PAHs for these products, samples stored in containers with rubber parts were selected for the analysis. The basis for method optimization was EPA Method 8310, which determines 16 priority PAHs in ground water and wastewater by HPLC using both UV and fluorescence detection. Using DAD, two channels were selected for detection, with one operating at 254 nm for the detection of nine PAHs and the other at 225 nm for the detection of seven PAHs. This method allowed for the detection of PAHs using external calibration with LODs and LOQs ranging from 0.001 to 0.060 μg/mL and from 0.003 to 0.167 μg/mL, respectively. Within-day precision, expressed as RSD, varied from 1.24 to 7.76% for PAH concentrations from 0.05 to 0.50 μg/mL, and intraday precision varied from 3.10 to 9.40% for the same concentration range. Method accuracy was confirmed by recoveries of 75–120% of the spiked samples. This method was applied for the determination of PAHs in three commercial infusion solutions and in nine different medications stored in syringes prior to administration to patients. Twelve of 16 PAHs were found in these samples. Total PAH concentrations varied from 0.13 to 13.50 μg/mL. Pyrene was the most prevalent contaminant, being present in 11 of 12 samples in concentrations ranging from 0.17 to 4.80 μg/mL. This method presented good sensitivity for the measurement of PAH in the target samples, allowing for the determination of the 16 priority PAHs in one run and in 30 min.

8.
JPEN J Parenter Enteral Nutr ; 41(6): 1037-1044, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-26979280

RESUMO

BACKGROUND: Rubber closures are the primary packaging material for sterile preparations intended for repeated use. Important features of rubber closures are achieved after additives are added to the elastomeric material that compounds the rubber. Among these additives is carbon black. Because of its origin, carbon black may contain polycyclic aromatic hydrocarbons (PAHs). The U.S. Environmental Protection Agency has identified 16 priority PAHs on the basis of concerns that they cause or might cause cancer in animals and humans. Regulatory agencies impose carbon black purity specifications based on limits for total PAHs (0.5 mg/kg) and benzo[a]pyrene (5 µg/kg) or benzo[a]pyrene only (250 µg/kg). PAHs in rubber packaging used for pharmaceutical formulations and in parenteral products stored in containers with rubber stoppers were investigated. METHODS: To this end, the method proposed by the National Institute for Occupational Safety and Health-based on high-performance liquid chromatography with ultraviolet and fluorescence detection-was adapted to determine the levels of PAHs in rubber stoppers (gray and red) and in lipid emulsions and amino acid solutions stored in bottles with rubber stoppers. RESULTS: The rubber materials were shown to contain 12 PAHs, in concentrations ranging from 0.25-3.31 µg/g. Only 1 of 18 samples (11 amino acid solutions and 7 lipid emulsions) was uncontaminated. The most prevalent contaminants were pyrene, benzo[a]pyrene, and fluoranthene. The total PAH concentrations in the samples ranged from 0.11-5.96 µg/mL. CONCLUSION: Components of parenteral nutrition may be contaminated with PAHs, and rubber stoppers represent a potential source of these contaminants.


Assuntos
Contaminação de Medicamentos , Soluções de Nutrição Parenteral/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Embalagem de Produtos , Borracha/química , Benzo(a)pireno/análise , Cromatografia Líquida de Alta Pressão , Fluorenos , Pirenos/análise , Reprodutibilidade dos Testes , Estados Unidos , United States Environmental Protection Agency
9.
Int J Food Sci Nutr ; 67(7): 789-96, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27381473

RESUMO

Food and agricultural industries generate substantial quantities of phenolic-rich by-products that could be valuable natural sources of antioxidants. The aim of this study was to identify and quantify the phenolic compounds and radical scavenging activities of two by-products (pomace and lees) from Vitis vinifera L. cv Pinot noir. We found a different distribution of phenolic classes (flavanols, flavonols, phenolic acids and stilbenes) and singular scavenging activity against free radicals (hydroxyl, superoxide and peroxyl radicals). The major class of phenolics in pomace was flavanols and in lees was flavonols, with catechin (117.9 ± 2.5 µg g(-1)) and quercetin (42.4 ± 1.2 µg g(-1)) being the most abundant individual compounds. We also found high potential on scavenging activity against superoxide radicals in pomace (80% of scavenging activity) and radical peroxyl (67% scavenging activity). These results show the possibility of using Pinot noir by-products as promising additives or as a source for the development of new products in different segments of the food and cosmetic industries.


Assuntos
Antioxidantes/análise , Frutas/química , Fenóis/análise , Vitis/química , Catequina/análise , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonóis/análise , Hidroxibenzoatos/análise , Quercetina/análise , Estilbenos/análise , Espectrometria de Massas em Tandem
10.
Artigo em Inglês | MEDLINE | ID: mdl-26560757

RESUMO

Methyl-xanthines and adrenergic stimulants, such as caffeine and synephrine, are commonly added to food supplements due to their stimulating and thermogenic effects. In addition, the abusive consumption of food supplements with ergogenic and aesthetic purposes has been observed worldwide. This work describes the study of caffeine, p-synephrine, hordenine, octopamine, tyramine, ephedrine and salicin as stimulants in dietary supplements marketed in Brazil for weight loss and physical fitness claims. A total of 94 different products were acquired from 30 Brazilian websites. Thus, the sampling of marketed supplements was performed in virtual commerce (e-commerce) with claims of weight loss, appetite reduction, fat burning and metabolism acceleration. The developed analytical method involved the separation of the stimulants by HPLC with diode array detection (HPLC-DAD) by using a gradient elution of flow rate (0.7-2.5 ml min(-1)) and mobile phase composition (0.1% H3PO4/methanol). The validated method was applied to the study of 46 dietary supplements. Caffeine, p-synephrine and ephedrine were found to be present as stimulants in 52% of the studied samples marketed as encapsulated or bulk forms. Caffeine was found to be present in concentrations that represent doses from 25.0 to 1476.7 mg day(-1). Synephrine was found in concentrations that represent doses from 59.1 to 127.0 mg day(-1). Ephedrine was found to be associated with caffeine in one formulation at a concentration representing a 26.1 mg day(-1) dosage.


Assuntos
Cafeína/análise , Estimulantes do Sistema Nervoso Central/análise , Suplementos Nutricionais/análise , Análise de Alimentos , Internet/economia , Aptidão Física , Redução de Peso , Brasil , Cromatografia Líquida de Alta Pressão
11.
Electrophoresis ; 35(21-22): 3212-30, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25070473

RESUMO

This review aims to describe the CE methods utilized for the determination of adulterants in herbal-based formulations marketed for different therapeutic purposes. The CE methods for screening and determination of pharmacologic adulterants are reviewed on the basis of the CE techniques and their detection methods. CZE and MEKC methods coupled to optical (UV), capacitively coupled contactless conductivity, and MS detection modes are discussed and reviewed. Worldwide adulteration cases related to pharmaceutical formulations containing herbs as the main active products are presented covering all the works published in the last four decades.


Assuntos
Contaminação de Medicamentos , Eletroforese Capilar/métodos , Preparações de Plantas , Espectrometria de Massas , Preparações de Plantas/análise , Preparações de Plantas/química , Preparações de Plantas/normas
12.
Artigo em Inglês | MEDLINE | ID: mdl-23574611

RESUMO

A reverse-phase (RP)-HPLC method is reported for determining L-tyrosine, p-octopamine, synephrine, tyramine and hordenine as chemical markers of the species Citrus aurantium in raw material, dry extracts and phytotherapeutic herbal formulations. Using RP-HPLC with diode array detection (DAD) and gradient elution, the amines were determined in 12 different products from different Brazilian states labelled as containing C. aurantium. The presence of the amines was confirmed by mass spectrometry using electrospray ionisation (ESI-MS/MS). This RP-HPLC method allowed the separation of the amines from complex mixtures containing caffeine, ephedrine, salicin and other raw materials (e.g. Garcinia camboja, Phaseolus vulgaris, Caralluma fimbriata, Cassia nomane, Ephedra sp. and Cordia ecalyculata). The method proved useful and selective for inspecting herbal medicines containing p-synephrine and structural analogues. The herbal products analysed had a p-synephrine content ranging from 0.005 to 4.0% (w/w).


Assuntos
Aminas Biogênicas/análise , Cromatografia Líquida de Alta Pressão/métodos , Citrus/química , Preparações Farmacêuticas/química , Padrões de Referência , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
13.
Ren Fail ; 35(3): 391-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23343454

RESUMO

BACKGROUND: Erythropoietin (EPO) formulations may comprise aluminum (Al) as a contaminant. Due to the toxicity of Al in chronic kidney disease patients, possible sources of Al were investigated. Since EPO formulations are stored in container-closure systems made of glass and rubber, and both contain Al, formulation ingredients may enable its leaching into the solution during shelf-life. METHODS: Individual solutions of formulation ingredients were stored in new glass vials and in contact with the rubber stopper and kept at 4 ± 2 °C. For 12 months, aliquots of each solution were collected for analysis. Fifteen commercial samples of EPO were analyzed for their Al content. Aluminum was determined by atomic absorption spectrometry. RESULTS: Glass and rubber are sources of Al for EPO formulations. Storage assay showed that citrate and phosphate (used as buffers) extracted high amounts of Al from the container/closure parts. The most important difference, however, was found when comparing liquid and lyophilized samples. While in liquid forms the Al level reached 943 µg/L, in lyophilized forms the level did not exceed 20 µg/L. The container system was also confirmed as a source of Al in reconstituted lyophilized samples. Al in reconstituted samples stored in their own vials increased 19-fold in 12 months. Lyophilized powders stored for 2 years in glass vials contained less Al than in 1 month after dissolution. CONCLUSION: The difference in the Al measured in liquid forms of EPO and in lyophilized powders suggests that the latter would be the best pharmaceutical form for CKD patients.


Assuntos
Alumínio/análise , Contaminação de Medicamentos , Embalagem de Medicamentos , Eritropoetina/química , Liofilização
14.
Neuropharmacology ; 67: 455-64, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23219656

RESUMO

Administration of the compound triterpene 3ß, 6ß, 16ß-trihidroxilup-20(29)-ene (TTHL) resulted in antinociceptive activity in several pain models in mice. Because pain and epilepsy have common mechanisms, and several anticonvulsants are clinically used to treat painful disorders, we investigated the anticonvulsant potential of TTHL. Behavioral and electrographic recordings revealed that pretreatment with TTHL (30 mg/kg; i.g.) increased the latencies to the first clonic seizure to the tonic-clonic and reduced the duration of the generalized seizures induced by the GABA(A) receptor antagonist PTZ (80 g; i.p.). The TTHL pretreatment also protected against PTZ-induced deleterious effects, as characterized by protein carbonylation, lipid peroxidation, [(3)H] glutamate uptake and the inhibition of Na(+),K(+)-ATPase (subunits α(1) and α(2)/α(3)). Although TTHL did not exhibit DPPH, ABTS radical scavenging activity per se and does not alter the binding of [(3)H]flunitrazepam to the benzodiazepinic site of the GABA(A) receptor, this compound was effective in preventing behavioral and EEG seizures, as well as the inhibition of Na(+),K(+)-ATPase induced by ouabain. These results suggest that the protection against PTZ-induced seizures elicited by TTHL is due to Na(+),K(+)-ATPase activity maintenance. In fact, experiments in homogenates of the cerebral cortex revealed that PTZ (10 mM) reduced Na(+),K(+)-ATPase activity and that previous incubation with TTHL (10 µM) protected against this inhibition. Collectively, these data indicate that the protection exerted by TTHL in this model of convulsion is not related to antioxidant activity or GABAergic activity. However, these results demonstrated that the effective protection of Na(+),K(+)-ATPase elicited by this compound protects against the damage due to neuronal excitability and oxidation that is induced by PTZ.


Assuntos
Fármacos Neuroprotetores/administração & dosagem , Estresse Oxidativo/fisiologia , Pentilenotetrazol/toxicidade , Convulsões/enzimologia , Convulsões/prevenção & controle , ATPase Trocadora de Sódio-Potássio/fisiologia , Triterpenos/administração & dosagem , Animais , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Injeções Intraventriculares , Camundongos , Fármacos Neuroprotetores/química , Estresse Oxidativo/efeitos dos fármacos , Convulsões/induzido quimicamente , Triterpenos/química
15.
J Environ Pathol Toxicol Oncol ; 32(4): 329-41, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24579785

RESUMO

This study investigated the protective effect of pecan nut (Carya illinoensis) shell aqueous extract (AE) on the oxidative and morphological status of rat testis treated with cyclophosphamide (CP). Wistar rats received water or AE (5%) ad libitum for 37 days. On day 30, half of each group received a single intraperitoneal administration of vehicle or CP 200 mg/kg. After 7 days, the animals were killed and their testis removed. Rats treated with CP presented reduced levels of lactate dehydrogenase, vitamin C, and gluthatione, as well as decreased catalase activity, increased lipid peroxidation levels and superoxide dismutase activity, no alteration in carbonyl protein levels, and a loss of morphological testicular integrity. In contrast, cotreatment with pecan shell AE totally prevented the decrease of lactate dehydrogenase and vitamin C levels and catalase activity and partially prevented the depletion of gluthatione levels. Moreover, it totally prevented the increase in superoxide dismutase activity and lipid peroxidation levels and maintained testicular integrity. These findings show the protective role of pecan shell AE in CP-induced testicular toxicity. The use of this phytotherapy may be considered to minimize deleterious effects related to this chemotherapy.


Assuntos
Carya , Ciclofosfamida/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Testículo/metabolismo , Testículo/patologia , Animais , Ácido Ascórbico/metabolismo , Catalase/metabolismo , Ciclofosfamida/efeitos adversos , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Modelos Animais , Nozes , Fitoterapia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo , Testículo/efeitos dos fármacos
16.
J Inorg Biochem ; 105(11): 1500-4, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21983256

RESUMO

Erythropoietin (EPO) is a glycoprotein that stimulates erythropoiesis and is clinically used for treating anemia during chronic renal failure and for anemia in preterm infants. EPO formulations usually have elevated rates of contamination due to aluminum (Al), which is toxic to both types of patients. Size-exclusion chromatography (SEC) coupled with graphite furnace atomic absorption spectrometry (GF AAS) was employed to separate proteins and to quantify the amount of aluminum present in the elution volume corresponding to EPO and, therefore, to evaluate possible binding. Because EPO formulations contain human serum albumin (HSA), a chromatographic method was optimized for the separation of these proteins. Subsequent to the chromatographic separation, 1-mL fractions of the column effluent were collected, and the Al content in these aliquots was measured by GF AAS. EPO and HSA samples were incubated with Al for 4h at 4°C and 37°C as well as for 16 h at 4°C and 37°C. Afterwards, they were injected into the chromatographic system. These samples were also submitted to ultrafiltration (10 and 50 kDa membranes), and Al was measured in the ultrafiltrates. The results showed that Al was present in the eluent volume corresponding to the EPO peak but not in the HSA peak in the chromatograms. Temperature strengthened the interaction because the Al present in the EPO fraction was 3 times higher at 37°C compared to 4°C. Thirty-eight percent of the Al present in a 2.4 µg/mL EPO standard solution, and approximately 50% of the Al in formulation samples containing approximately 11 µg/mL EPO and either citrate or phosphate, were non-ultrafiltrable, which suggests that EPO is an effective Al acceptor in vitro.


Assuntos
Alumínio/química , Eritropoetina/química , Cromatografia em Gel , Eritropoetina/isolamento & purificação , Humanos , Ligação Proteica , Albumina Sérica/isolamento & purificação , Espectrofotometria Atômica
17.
Forensic Sci Int ; 204(1-3): 6-12, 2011 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-20554134

RESUMO

Obesity that is associated with a high consumption of slimming substances is considered a public health problem around the world. In this context, the increasing consumption of phytotherapeutic formulations as alternative obesity treatments has revealed the presence of synthetic pharmaceuticals as adulterants. The illegally added adulterants are frequently anorexic, anxiolytic, and antidepressant pharmaceuticals. This review aims to describe the analytical methodologies utilized for the determination of adulterants in slimming phytotherapeutic formulations. Furthermore, this review describes some important adulteration cases, which occurred mainly in Europe, Asia, Brazil, and the USA.

18.
Biol Trace Elem Res ; 141(1-3): 76-85, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20499205

RESUMO

The distribution of Cd (II) and Pb (II) among amino acids in parenteral nutrition formulations was investigated by coupling ion-chromatography (HPLC/IC) and electrothermal atomic absorption spectrometry. The methodology was based on ion-exchange separation and fluorimetric amino acid detection after post-column derivatization. Cd (II) and Pb (II) were assayed in 500-µL fractions of the column effluent. The distribution of Cd (II) and Pb (II) in alanine (Ala), aspartic acid (Asp), glutamic acid (Glu), glycine (Gly), histidine (His), methionine (Met), phenylalanine (Phe), serine (Ser), and threonine (Thr) were analyzed by monitoring changes in the concentration of free amino acids by HPLC/IC. The results indicated that Cd (II) and Pb (II) were distributed according to the following trend: Gly-Cd > Gly-Pb > Ala-Cd > Ala-Pb > His-Cd ∼ His-Pb > Thr-Cd > Thr-Pb > Phe-Cd ∼ Phe-Pb ∼ Asp-Cd ∼ Asp-Pb ∼ Met-Cd ∼ Met-Pb ∼ Glu-Cd ∼ Glu-Pb > Ser-Cd ∼ Ser-Pb. The effects of amino acid concentration and stability constants of amino acid-metal complexes are discussed.


Assuntos
Aminoácidos/química , Cádmio/química , Cromatografia , Chumbo/química , Soluções de Nutrição Parenteral/química , Espectrofotometria Atômica , Humanos , Metais Pesados
19.
Nanoscale Res Lett ; 5(10): 1603-10, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21076700

RESUMO

The improvement of the rutin photostability and its prolonged in vitro antioxidant activity were studied by means of its association with nanostructured aqueous dispersions. Rutin-loaded nanocapsules and rutin-loaded nanoemulsion showed mean particle size of 124.30 ± 2.06 and 124.17 ± 1.79, respectively, polydispersity index below 0.20, negative zeta potential, and encapsulation efficiency close to 100%. The in vitro antioxidant activity was evaluated by the formation of free radical ·OH after the exposure of hydrogen peroxide to a UV irradiation system. Rutin-loaded nanostructures showed lower rutin decay rates [(6.1 ± 0.6) 10(-3) and (5.1 ± 0.4) 10(-3) for nanocapsules and nanoemulsion, respectively] compared to the ethanolic solution [(35.0 ± 3.7) 10(-3) min(-1)] and exposed solution [(40.1 ± 1.7) 10(-3) min(-1)] as well as compared to exposed nanostructured dispersions [(19.5 ± 0.5) 10(-3) and (26.6 ± 2.6) 10(-3), for nanocapsules and nanoemulsion, respectively]. The presence of the polymeric layer in nanocapsules was fundamental to obtain a prolonged antioxidant activity, even if the mathematical modeling of the in vitro release profiles showed high adsorption of rutin to the particle/droplet surface for both formulations. Rutin-loaded nanostructures represent alternatives to the development of innovative nanomedicines.

20.
Forensic Sci Int ; 202(1-3): 75-81, 2010 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-20472377

RESUMO

The use of synthetic pharmaceuticals in phytotherapeutics can be defined as an illegal practice, since these compounds are normally present as non-declared compounds in the phytotherapeutical formulations. This work aims to show the development of an analytical method based on adsorptive cathodic stripping voltammetry (AdCSV) for the simultaneous determination of 1,4-benzodiazepines and amfepramone. The developed method was used to measure seven benzodiazepines (clonazepam, flurazepam, alprazolam, midazolam, medazepam, chlordiazepoxide, and diazepam) and amfepramone in slimming formulations that have been commercialized in Brazil. This method permits the screening of adulterant classes in a single voltammetric run by using a hanging mercury drop electrode as a working electrode and Ringer buffer (pH 10.0) as a supporting electrolyte. Recovery values ranging from 92.0% to 117.0% demonstrate the reliability of the method in the determination of adulterants in real samples. Among the 12 samples studied by the proposed method, 4 were demonstrated to be adulterated by 1,4-benzodiazepines.

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