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1.
J Anal Methods Chem ; 2019: 1863910, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467766

RESUMO

The quality of over-the-counter (OTC) pain relievers is important to ensure the safety of the marketed products in order to maintain the overall health care of patients. In this study, the multivariate curve resolution-alternating least squares (MCR-ALS) chemometric method was developed and validated for the resolution and quantification of the most commonly consumed OTC pain relievers (acetaminophen, acetylsalicylic acid, ibuprofen, naproxen, and caffeine) in commercial drug formulations. The analytical performance of the developed chemometric methods such as root mean square error of prediction, bias, standard error of prediction, relative error of prediction, and coefficients of determination was calculated for the developed model. The obtained results are linear with concentration in the range of 0.5-7 µg/mL for acetaminophen and 0.5-3.5 and 0.5-3 µg/mL for naproxen and caffeine, respectively, while the linearity ranges for acetyl salicylic acid and ibuprofen were 1-15 µg/mL. High values of coefficients of determination ≥0.9995 reflected high predictive ability of the developed model. Good recoveries ranging from 98.0% to 99.7% were obtained for all analytes with relative standard deviations (RSDs) not higher than 1.62%. The optimized method was successfully applied for the analysis of the studied drugs either in their single or coformulated pharmaceutical products without any separation step. The optimized method was also compared with a reported HPLC method using paired t-test and F-ratio at 95% confidence level, and the results showed no significant difference regarding accuracy and precision. The developed method is eco-friendly, simple, fast, and amenable for routine analysis. It could be used as a cost-effective alternative to chromatographic techniques for the analysis of the studied drugs in commercial formulations.

2.
Acta Pharm ; 69(2): 217-231, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31259724

RESUMO

The study presents the application of multivariate curve resolution alternating least squares (MCR-ALS) with a correlation constraint for simultaneous resolution and quantification of ketoprofen, naproxen, paracetamol and caffeine as target analytes and triclosan as an interfering component in different water samples using UV-Vis spectrophotometric data. A multivariate regression model using the partial least squares regression (PLSR) algorithm was developed and calculated. The MCR-ALS results were compared with the PLSR obtained results. Both models were validated on external sample sets and were applied to the analysis of real water samples. Both models showed comparable and satisfactory results with the relative error of prediction of real water samples in the range of 1.70-9.75 % and 1.64-9.43 % for MCR-ALS and PLSR, resp. The obtained results show the potential of MCR-ALS with correlation constraint to be applied for the determination of different pharmaceuticals in complex environmental matrices.


Assuntos
Monitoramento Ambiental/métodos , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Análise dos Mínimos Quadrados , Análise Multivariada , Espectrofotometria/métodos
3.
J AOAC Int ; 102(2): 465-472, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30241575

RESUMO

Background: Considering the environmental impact of analytical procedures necessitates replacing the polluting analytical methods with green alternatives. Objective: This study aims to develop and validate a multivariate curve resolution-alternating least-squares (MCR-ALS) method with correlation constraint for the simultaneous determination of theophylline, ambroxol, and guaifenesin as target analytes in the presence of methylparaben and propylparaben as interfering components. In addition, a partial least-squares regression (PLSR) method was also developed and optimized. Method: The developed methods were validated according to International Conference on Harmonization guidelines and successfully applied for the quantification of the target analytes in different pharmaceutical dosage forms. Results: Figures of merit such as root mean square error of prediction, bias, standard error of prediction, and relative error of prediction for both models were calculated, and they showed similar and satisfactory results. Correlation coefficients ranged between 0.9988 and 0.9992, reflecting high predictive ability. The optimized methods were compared with a reported HPLC method using one-way analysis of variance and showed no significant difference regarding accuracy and precision. Conclusions: The proposed chemometrics methods can be used as an eco-friendly alternative for chromatographic techniques for the quality control analysis of the studied mixture in different pharmaceutical dosage forms. Highlights: An MCR-ALS model was developed. The developed model was compared with a PLSR model. Both models were validated and successfully used for the determination of a multicomponent pharmaceutical mixture. The developed method is eco-friendly, fast, reliable, and cost-effective.


Assuntos
Ambroxol/análise , Guaifenesina/análise , Teofilina/análise , Formas de Dosagem , Análise dos Mínimos Quadrados , Análise Multivariada
5.
J AOAC Int ; 101(6): 1781-1787, 2018 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29895351

RESUMO

Background: Green analytical chemistry (GAC) aims to eliminate or minimize the amount of hazardous solvents consumed and generated daily worldwide. Considering the environmental impact of all analytical procedures and replacing the polluting methodologies with clean ones is of a paramount interest. Objective: This work aims to develop and validate a sustainable, fast, and economic ultrahigh-performance liquid chromatography method for simultaneous determination of methylxanthines in commercial tea samples as well as to evaluate the greenness profile of the proposed method using two greenness assessment tools: National Environmental Methods Index (NEMI) and analytical Eco-scale. Methods: The method was designed based on applying GAC principles in method development. The green chromatography approach was applied by using benign mobile phases. The chromatographic separation was optimized to minimize sample preparation, achieve short analysis time with low solvent consumption, and minimize waste generation. Results: All the studied analytes were separated in only 1.7 min. The detection limits of the studied analytes ranged from 0.015 to 0.03 mg/L, while LOQs were in the range of 0.05 to 0.1 µg/L with UV detection. The proposed method neither uses nor generates harmful chemicals, it passes the four quadrants of the NEMI greenness profile, and it has a high Eco-scale score. Conclusions: Compared with the reported methods, the proposed method is greener, more economical, and faster; therefore, it can be used as a green alternative to the existing conventional methods for routine analysis of the studied analytes without harming the environment.


Assuntos
Cafeína/análise , Cromatografia Líquida de Alta Pressão/métodos , Química Verde/métodos , Chá/química , Teobromina/análise , Limite de Detecção
6.
Gates Open Res ; 2: 3, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29630066

RESUMO

The Microbe Directory is a collective research effort to profile and annotate more than 7,500 unique microbial species from the MetaPhlAn2 database that includes bacteria, archaea, viruses, fungi, and protozoa. By collecting and summarizing data on various microbes' characteristics, the project comprises a database that can be used downstream of large-scale metagenomic taxonomic analyses, allowing one to interpret and explore their taxonomic classifications to have a deeper understanding of the microbial ecosystem they are studying. Such characteristics include, but are not limited to: optimal pH, optimal temperature, Gram stain, biofilm-formation, spore-formation, antimicrobial resistance, and COGEM class risk rating. The database has been manually curated by trained student-researchers from Weill Cornell Medicine and CUNY-Hunter College, and its analysis remains an ongoing effort with open-source capabilities so others can contribute. Available in SQL, JSON, and CSV (i.e. Excel) formats, the Microbe Directory can be queried for the aforementioned parameters by a microorganism's taxonomy. In addition to the raw database, The Microbe Directory has an online counterpart ( https://microbe.directory/) that provides a user-friendly interface for storage, retrieval, and analysis into which other microbial database projects could be incorporated. The Microbe Directory was primarily designed to serve as a resource for researchers conducting metagenomic analyses, but its online web interface should also prove useful to any individual who wishes to learn more about any particular microbe.

7.
Anal Bioanal Chem ; 408(25): 6929-44, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27349918

RESUMO

Greening the analytical methods used for analysis of pharmaceuticals has been receiving great interest aimed at eliminating or minimizing the amount of organic solvents consumed daily worldwide without loss in chromatographic performance. Traditional analytical LC techniques employed in pharmaceutical analysis consume tremendous amounts of hazardous solvents and consequently generate large amounts of waste. The monetary and ecological impact of using large amounts of solvents and waste disposal motivated the analytical community to search for alternatives to replace polluting analytical methodologies with clean ones. In this context, implementing the principles of green analytical chemistry (GAC) in analytical laboratories is highly desired. This review gives a comprehensive overview on different green LC pathways for implementing GAC principles in analytical laboratories and focuses on evaluating the greenness of LC analytical procedures. This review presents green LC approaches for eco-friendly analysis of pharmaceuticals in industrial, biological, and environmental matrices. Graphical Abstract Green pathways of liquid chromatography for more eco-friendly analysis of pharmaceuticals.


Assuntos
Cromatografia Líquida/métodos , Química Verde/métodos , Preparações Farmacêuticas/análise , Cromatografia Líquida/instrumentação , Química Verde/instrumentação , Interações Hidrofóbicas e Hidrofílicas , Miniaturização/instrumentação , Miniaturização/métodos , Preparações Farmacêuticas/isolamento & purificação , Solventes/química
8.
Talanta ; 132: 739-52, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25476373

RESUMO

Green analytical chemistry is an aspect of green chemistry which introduced in the late nineties. The main objectives of green analytical chemistry are to obtain new analytical technologies or to modify an old method to incorporate procedures that use less hazardous chemicals. There are several approaches to achieve this goal such as using environmentally benign solvents and reagents, reducing the chromatographic separation times and miniaturization of analytical devices. Traditional methods used for the analysis of pharmaceutically active compounds require large volumes of organic solvents and generate large amounts of waste. Most of them are volatile and harmful to the environment. With the awareness about the environment, the development of green technologies has been receiving increasing attention aiming at eliminating or reducing the amount of organic solvents consumed everyday worldwide without loss in chromatographic performance. This review provides the state of the art of green analytical methodologies for environmental analysis of pharmaceutically active compounds in the aquatic environment with special emphasis on strategies for greening liquid chromatography (LC). The current trends of fast LC applied to environmental analysis, including elevated mobile phase temperature, as well as different column technologies such as monolithic columns, fully porous sub-2 µm and superficially porous particles are presented. In addition, green aspects of gas chromatography (GC) and supercritical fluid chromatography (SFC) will be discussed. We pay special attention to new green approaches such as automation, miniaturization, direct analysis and the possibility of locating the chromatograph on-line or at-line as a step forward in reducing the environmental impact of chromatographic analyses.


Assuntos
Química Verde/métodos , Preparações Farmacêuticas/análise , Poluentes Químicos da Água/análise , Água/química , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Cromatografia com Fluido Supercrítico , Conservação dos Recursos Naturais , Temperatura Alta , Cinética , Solventes/química
9.
J Sep Sci ; 36(2): 252-61, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23229730

RESUMO

Fast separations are very desirable in laboratories that analyze large numbers of samples per day or those needing short turn-around times. Traditional HPLC methods using conventional stationary phases and standard column dimensions require significant amounts of organic solvents and generate large volumes of waste. With growing awareness about the environment, the development of green technologies has been receiving increasing attention. In this work, a very fast green analytical method based on LC-UV using a short narrow bore column packed with fully porous sub-2 µm particles has been developed for simultaneous determination of nine pharmaceuticals in wastewater and surface water. The chromatographic separation was optimized in order to achieve short analysis time and good resolution for all analytes in a single run. All analytes could be separated in 1 min with good resolution. Sample preparation was executed by solid phase extraction using Oasis HLB cartridges. The method developed was validated based on parameters such as linearity, precision, accuracy, detection, and quantification limits. The recovery ranged from 70.9 to 92.5% with SDs not higher than 5.4%, except for acetaminophen and sulphanilamide. LODs ranged from 0.6-2.5 µg/L, while the LOQs were in the range 2-8 µg/L.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Preparações Farmacêuticas/química , Poluentes Químicos da Água/química , Adsorção , Cromatografia Líquida de Alta Pressão/instrumentação , Química Verde , Preparações Farmacêuticas/isolamento & purificação , Porosidade , Resinas Sintéticas/química , Extração em Fase Sólida , Águas Residuárias/análise , Poluentes Químicos da Água/isolamento & purificação
10.
Talanta ; 100: 80-9, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23141315

RESUMO

The development of fused-core silica stationary phases was considered a breakthrough in column manufacturing. In this study, a fast LC-UV method was developed and validated for the simultaneous determination of 25 emerging contaminants in surface water and wastewater. The selected analytes belonged to various classes such as veterinary antibiotics, central nervous system stimulants, non-steroidal anti-inflammatory drugs, steroids and preservatives. The chromatographic separation was optimized in order to achieve suitable retention times and good resolution for all analytes in a single run using solvent gradient and flow rate gradient. All analytes eluted within 10 min on a Kinetex(®) C18 column packed with fused core particles. Sample preparation was executed with solid-phase extraction on Oasis HLB cartridges. The method was validated by assessing linearity, selectivity, accuracy, precision, limits of detection and limits of quantification. Good recoveries were obtained for all analytes ranging from 67.5% to 97.0% with standard deviations not higher than 5.7%, except for acetaminophen, sulphanilamide and acetyl salicylic acid, for which lower recoveries were obtained. The detection limits ranged from 1.5 to 15 µg L(-1), while limits of quantification were in the range from 5 to 50 µg L(-1). The short analysis time achieved by this method allowed analysis of a large number of samples in a short time, minimizing organic solvent consumption and lowering LC solvents cost. This fast method offers benefits both environmentally and economically.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Tamanho da Partícula , Dióxido de Silício/química , Águas Residuárias/química , Poluentes Químicos da Água/análise , Lagos/química , Limite de Detecção , Porosidade , Reprodutibilidade dos Testes , Rios/química , Extração em Fase Sólida , Solventes/química , Fatores de Tempo , Poluentes Químicos da Água/isolamento & purificação
11.
J Sep Sci ; 35(2): 216-24, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22162242

RESUMO

High temperature in HPLC is considered a valuable tool helping to overcome the increase in the column backpressure when using small packing particles such as sub-2 µm, as it allows reduction in the mobile-phase viscosity. In this study, a fast analytical method based on HPLC-UV was developed using a sub-2 µm column at elevated temperature for the simultaneous determination of nine sulphonamides. Owing to the lower viscosity of the mobile phase, the separation could be achieved in 3 min at 60°C for all analytes. The effect of temperature, the organic modifier percentage and the flow rate on the retention time was studied. The method developed was used for the determination of selected sulphonamides in surface and wastewater samples. Sample preparation was carried out by solid-phase extraction on Oasis HLB cartridges. The method developed was validated based on the linearity, precision, accuracy, detection and quantification limits. The recovery ranged from 70.6 to 96 % with standard deviations not higher than 4.7%, except for sulphanilamide. Limits of detection ranged from 1 to 10 µg/L after optimization of all analytical steps. This method has the highest performance in terms of analytical speed compared with other published HPLC-UV methods for the determination of sulphonamides in water.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Sulfonamidas/análise , Poluentes Químicos da Água/análise , Animais , Cromatografia Líquida de Alta Pressão/instrumentação , Resíduos de Drogas/análise , Humanos , Lagos/análise , Tamanho da Partícula , Rios/química , Extração em Fase Sólida/métodos , Temperatura Ambiente , Águas Residuárias/análise
12.
Anal Chim Acta ; 702(1): 136-43, 2011 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-21819871

RESUMO

A high efficiency HPLC method was developed by coupling three sub-2 µm columns in series and operating them at high temperature for the separation of selected non-steroidal anti-inflammatory drugs and veterinary antibiotics in environmental samples. The separation was performed at 80°C to reduce the solvent viscosity, thus reducing the column backpressure. The chromatographic performance of high temperature-extended column length HPLC method was used to determine the most widely used non-steroidal anti-inflammatory drugs and veterinary antibiotics such as sulphonamides in wastewater samples. The method could simultaneously determine 24 pharmaceuticals in short analysis time with high efficiency. The method involved pre-concentration and clean-up by solid phase extraction (SPE) using Oasis HLB extraction cartridges. It was validated based on linearity, precision, detection and quantification limits, selectivity and accuracy. Good recoveries were obtained for all analytes ranging from 72.7% to 98.2% with standard deviations not higher than 6%, except for acetaminophen and acetyl salicylic acid, for which low recovery was obtained. The detection limits of the studied pharmaceuticals ranged from 2 to 16 µg L(-1), while limits of quantification were in the range from 7 to 54 µg L(-1) with UV detection.


Assuntos
Antibacterianos/análise , Anti-Inflamatórios não Esteroides/análise , Cromatografia Líquida/instrumentação , Sulfonamidas/análise , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão/métodos , Temperatura Alta , Análise dos Mínimos Quadrados , Limite de Detecção , Extração em Fase Sólida/métodos
13.
J AOAC Int ; 93(2): 536-48, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20480901

RESUMO

Three methods were developed for the determination of two ternary mixtures containing drotaverine hydrochloride (DR) with caffeine and paracetamol (mixture 1) and DR with metronidazole and diloxanide furoate (mixture 2). The first method depends on HPLC separation on an RP C18 column at ambient temperature with the mobile phase methanol-water, pH 3.1 (50 + 50, v/v) and UV detection at 213 nm for mixture 1, and the mobile phase acetonitrile-25 mM potassium dihydrogen phosphate, pH 4.6 (55 + 45, v/v) with UV detection at 235 nm for mixture 2. The other two chemometric methods applied were partial least squares (PLS-1) and principal component regression (PCR). These approaches were successfully applied to quantify the five drugs in two ternary mixtures using information included in the UV absorption spectra of appropriate solutions in the wavelength range of 210-300 nm with 1 nm intervals. Calibration of PCR and PLS-1 models was evaluated by internal validation (prediction of compounds in its own designed training set of calibration), by cross-validation (obtaining statistical parameters that show the efficiency for a calibration fit model), and by external validation (using laboratory-prepared mixtures and pharmaceutical preparations). The proposed methods were successfully applied for the determination of the two ternary combinations in laboratory-prepared mixtures and commercial tablets; the results of PLS-1 and PCR methods were compared with the HPLC method, and a good agreement was found.


Assuntos
Cromatografia Líquida/métodos , Papaverina/análogos & derivados , Espectrofotometria/métodos , Acetaminofen/análise , Cafeína/análise , Calibragem , Técnicas de Química Analítica , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/instrumentação , Furanos/análise , Concentração de Íons de Hidrogênio , Metanol/química , Metronidazol/análise , Modelos Químicos , Papaverina/análise , Papaverina/química , Fosfatos/química , Compostos de Potássio/química , Reprodutibilidade dos Testes , Espectrofotometria/instrumentação , Espectrofotometria Ultravioleta/métodos , Tecnologia Farmacêutica/métodos
14.
J AOAC Int ; 90(5): 1250-7, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17955969

RESUMO

A high-performance liquid chromatographic (HPLC) method was developed for determination of oxyphenonium bromide (OX) and its degradation product. The method was based on the HPLC separation of OX from its degradation product, using a cyanopropyl column at ambient temperature with mobile phase of acetonitrile-25 mM potassium dihydrogen phosphate, pH 3.4 (50 + 50, v/v). UV detection at 222 nm was used for quantitation based on peak area. The method was applied to the determination of OX and its degradation product in tablets. The proposed method was also used to investigate the kinetics of the acidic and alkaline degradation of OX at different temperatures, and the apparent pseudo first-order rate constant, half-life, and activation energy were calculated. The pH-rate profile of the degradation of OX in Britton-Robinson buffer solutions within the pH range 2-12 was studied.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Oxifenônio/análise , Oxifenônio/química , Acetonitrilos/química , Calibragem , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Concentração de Íons de Hidrogênio , Cinética , Modelos Lineares , Modelos Químicos , Reprodutibilidade dos Testes , Espectrofotometria Ultravioleta/métodos , Comprimidos , Tecnologia Farmacêutica/métodos , Temperatura Ambiente
15.
J Pharm Biomed Anal ; 43(3): 973-82, 2007 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-17046190

RESUMO

Three methods are developed for the determination of two multicomponent mixtures containing guaiphenesine (GU) with salbutamol sulfate (SL), methylparaben (MP) and propylparaben (PP) [mixture 1]; and acephylline piperazine (AC) with bromhexine hydrochloride (BX), methylparaben (MP) and propylparaben (PP) [mixture 2]. The resolution of the two multicomponent mixtures has been accomplished by using numerical spectrophotometric methods such as partial least squares (PLS-1) and principal component regression (PCR) applied to UV absorption spectra of the two mixtures. In addition HPLC method was developed using a RP 18 column at ambient temperature with mobile phase consisting of acetonitrile-0.05 M potassium dihydrogen phosphate, pH 4.3 (60:40, v/v), with UV detection at 243 nm for mixture 1, and mobile phase consisting of acetonitrile-0.05 M potassium dihydrogen phosphate, pH 3 (50:50, v/v), with UV detection at 245 nm for mixture 2. The methods were validated in terms of accuracy, specificity, precision and linearity in the range of 20-60 microg ml(-1) for GU, 1-3 microg ml(-1) for SL, 20-80 microg ml(-1) for AC, 0.2-1.8 microgml(-1) for PP and 1-5 microg ml(-1) for BX and MP. The proposed methods were successfully applied for the determination of the two multicomponent combinations in laboratory prepared mixtures and commercial syrups.


Assuntos
Broncodilatadores/análise , Albuterol/análise , Bromoexina/análise , Calibragem , Cromatografia Líquida , Combinação de Medicamentos , Expectorantes/análise , Guaifenesina/análise , Indicadores e Reagentes , Análise dos Mínimos Quadrados , Parabenos/análise , Piperazina , Piperazinas/análise , Padrões de Referência , Reprodutibilidade dos Testes , Solventes , Espectrofotometria Ultravioleta , Teofilina/análogos & derivados , Teofilina/análise
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