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1.
J Chromatogr A ; 1627: 461395, 2020 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-32823100

RESUMO

Nowadays, enantioseparation of racemic pharmaceuticals in preparations is a prime concern by drug authorities across the globe. In the present work, it was attempted to develop novel enantioselective extraction method for five clinically used drugs (atenolol, propranolol, metoprolol, racecadotril, and raceanisodamine in their tablets) as racemates. The enantioselective solid-liquid extraction of these racemic drugs was carried out successfully by the use of chiral ionic liquid (CIL) in combination with a metal organic framework (MOF) for the first time. The composite CIL@MOF was synthesized from tropine based chiral ionic liquids with L-proline anion ([CnTr][L-Pro], n=3-6) and HKUST-1 type MOF, which was comprehensively characterized before being used as sorbent for enantioselective dispersive solid-liquid extraction. Preliminary selection of appropriate CIL was carried out on thin layer chromatography (TLC); under the joint participation of copper ion in the developing reagent, [C3Tr][L-Pro] ionic liquid showed better resolution performance with ΔRf value of 0.35 between the enantiomers was obtained for racemic atenolol. Moreover, the effect of copper salt dosage, amount of CIL, soli-liquid ratio and extraction time were investigated. The optimal conditions were obtained after thorough investigations; i.e. sample solution: ethanol, elution solvent: methanol, solid-liquid ratio: 12.5 mg:50 mL, amount of copper salt: 8 mg L-1, amount of impregnated CIL: 30% and extraction time of 30 min. As a result, enantiomeric excess values are 90.4%, 95%, 92%, 81.6% and 83.2% for atenolol, propranolol, metoprolol, racecadotril and raceanisodamine, respectively. The developed enantioselective method was validated following ICH guidelines and it was proved to be simple, effective and enantioselective way for separation of racemic pharmaceuticals with similar behaviors.


Assuntos
Líquidos Iônicos/química , Estruturas Metalorgânicas/química , Preparações Farmacêuticas/isolamento & purificação , Extração em Fase Sólida/métodos , Antagonistas Adrenérgicos beta/análise , Antagonistas Adrenérgicos beta/isolamento & purificação , Atenolol/análise , Atenolol/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Cobre/química , Metoprolol/análise , Metoprolol/isolamento & purificação , Preparações Farmacêuticas/análise , Propranolol/análise , Propranolol/isolamento & purificação , Solventes/química , Estereoisomerismo
2.
J Chromatogr A ; 1629: 461501, 2020 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-32841768

RESUMO

Metabolic stability tests are one of the fundamental steps at the preclinical stages of new drug development. Microsomes, used as a typical enzymatic model of liver biotransformation, can be a challenging matrix for analytical scientists due to a high concentration of cellular proteins and membrane lipids. In the work, we propose a new procedure integrating biotransformation reaction with SPME-like protocol for sample clean-up. It is beneficial to increase the overall quality of results in contrary to the typical protein precipitation approach. A set of ten arylpiperazine analogs, six of which are considered promising drug candidates (and four are accepted drugs) were used as a probe to assess the goodness of the newly proposed approach. In order to promote an efficient extraction protocol, a new, miniaturized shape of a sorbent, suitable to perform the extraction in 100 µL of the sample has been designed. Termination of the biotransformation process by protein denaturation with hot water was additionally evaluated. A quantitative structure-property relationship (QSPR) study using Orthogonal Partial Least Squares (OPLS) technique to reveal insights to the sorption mechanism was also performed. The obtained results showed the new 3D-printed sorbent can be an attractive basis for the new sample preparation approach for metabolic stability studies and an alternative for commercially available protocols based on solid-phase microextraction (SPME) or solid-phase extraction (SPE) principles.


Assuntos
Preparações Farmacêuticas/química , Impressão Tridimensional , Adsorção , Análise dos Mínimos Quadrados , Preparações Farmacêuticas/isolamento & purificação , Relação Quantitativa Estrutura-Atividade , Microextração em Fase Sólida
3.
J Chromatogr A ; 1628: 461452, 2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32822990

RESUMO

Comprehensive two-dimensional liquid chromatography (LC×LC) offers increased peak capacity, resolution and selectivity compared to one-dimensional liquid chromatography. It is commonly accepted that the technique produces the best results when the separation mechanisms in the two dimensions are completely orthogonal, which necessitates the use of gradient elution for each second-dimension fraction. Recently, the use of similar separation mechanisms in both dimensions has been gaining popularity, but full or shifted gradients are still used for each second dimension fraction. Herein, we argue that when the separation mechanisms are correlated in the two dimensions, the best results can be obtained with the use of parallel gradients in the second dimension, which makes the technique nearly as user-friendly as comprehensive two-dimensional gas chromatography. This has been illustrated through the separation of a mixture of 39 pharmaceutical compounds using reversed phase in both dimensions. Different selectivity in the second dimension was obtained through the use of different stationary phase chemistries and/or mobile phase organic modifiers. The best coverage of the separation space was obtained when parallel gradients were applied in both dimensions, and the same was true for practical peak capacity.


Assuntos
Cromatografia Líquida/métodos , Algoritmos , Preparações Farmacêuticas/isolamento & purificação
4.
J Chromatogr A ; 1624: 461218, 2020 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-32540066

RESUMO

In this study, amylose- and cellulose-phenylcarbamate-based chiral columns with different chiral-selector (CS) chemistries were compared to each other for the separation of enantiomers of basic chiral analytes in acetonitrile and aqueous-acetonitrile mobile phases in HPLC. For two chemistries the amylose-based columns with coated and immobilized CSs were also compared. The comparison of CSs containing only electron-donating or electron-withdrawing substituents with those containing both electron-donating and electron-withdrawing substituents showed opposite results for the studied set of chiral analytes in the case of amylose and cellulose derivatives. Along with the chemistry of CS the focus was on the behavior of polysaccharide phenylcarbamates in acetonitrile versus aqueous acetonitrile as eluents. In agreement with earlier results, it was found that in contrast to the commonly accepted view, polysaccharide phenylcarbamates do not behave as typical reversed-phase materials for basic analytes either. In the range of water content in the mobile phase of up to 20-30% v/v the behavior of these CSs is similar to hydrophilic interaction liquid chromatography (HILIC)-type adsorbents. This means that with increasing water content in the mobile phase up to 20-30% v/v, the retention of analytes mostly decreases. The important finding of this study is that the separation efficiency improves for most analytes when switching from pure acetonitrile to aqueous acetonitrile. Therefore, in spite of reduced retention, the separation of enantiomers improves and thus, the HILIC-range of mobile phase composition, offering shorter analysis time and better peak resolution, is advantageous over pure polar-organic solvent mode. Interesting examples of enantiomer elution order (EEO) reversal were observed for some analytes based on the content of water in the mobile phase on Lux Cellulose-1 and Lux Amylose-2 columns.


Assuntos
Amilose/química , Celulose/química , Cromatografia Líquida de Alta Pressão/métodos , Preparações Farmacêuticas/isolamento & purificação , Fenilcarbamatos/química , Acetonitrilos/química , Elétrons , Etanolaminas/análise , Etanolaminas/isolamento & purificação , Preparações Farmacêuticas/análise , Propanolaminas/análise , Propanolaminas/isolamento & purificação , Propranolol/análise , Propranolol/isolamento & purificação , Estereoisomerismo , Água/química
5.
J Chromatogr A ; 1623: 461171, 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32505277

RESUMO

A novel disposable styrene based solid-phase microextraction (SPME) fiber was synthesized for the detection of lipid-lowering and antihypertensive drugs in real aquatic environment. Styrene and poly(ethylene glycol) diacrylate were co-polymerized on quartz fibers by thermal polymerization in capillary molds. The polymeric fiber possessed a homogeneous, dense as well as porous surface, showing excellent chemical and mechanical stability. The performance of the fiber was evaluated through the extraction of seven pharmaceuticals by coupling SPME with high performance liquid chromatography-tandem mass spectrometry under the optimized extraction conditions. The extraction efficiency of the fiber was up to 278 times of PDMS fiber and the enrichment factors ranged from 55 to 1183. The limits of detection were in the range from 1.7 ng L-1 to 11.7 ng L-1, with good reproducibility. Moreover, the fiber was used in the real water samples of the Pearl River Delta. The recoveries of the target analytes from river water and sea water samples at different spiked concentrations were in the range from 84.1% to 133.4% and from 81.5% to 105.5%, respectively.


Assuntos
Preparações Farmacêuticas/análise , Microextração em Fase Sólida/métodos , Poluentes Químicos da Água/análise , Cromatografia Líquida de Alta Pressão , Preparações Farmacêuticas/isolamento & purificação , Polietilenoglicóis/química , Polimerização , Reprodutibilidade dos Testes , Rios/química , Água do Mar/química , Estireno/química , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/isolamento & purificação
7.
Chemosphere ; 258: 127336, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32563916

RESUMO

Modification of commercially available Douglas fir biochar (BC) by iron oxide nanoparticle precipitation from aqueous Fe2+/Fe3+ salt solutions upon NaOH treatment generated a hybrid adsorbent (MBC) that removed three common emerging aqueous contaminants, a stimulant (caffeine) and two anti-inflammatory drugs (ibuprofen and acetylsalicylic acid) through batch sorption. Fe3O4 particles (12.3 ± 7.1 nm diameter fundamental particles with aggregates 1-17 µm diameter) dispersed on the biochar surface provided magnetization and created new adsorption sites for the contaminant uptake. These smaller quasi-spherical, octahedral Fe3O4 particles as well as the spindle-like Fe2O3 particles were observed with scanning electron microscopy (SEM) images of MBC, and the composition was confirmed by X-ray powder diffraction (XRD). Adsorption features were evaluated using Langmuir and Freundlich isotherm models. The Langmuir adsorption capacities on MBC at 35 °C have increased from 24.6 ± 0.4 to 75.1 ± 1.8 mg/g for caffeine, 17.5 ± 0.4 to 39.9 ± 1.2 mg/g for ibuprofen and 106.2 ± 2.8 to 149.9 ± 4.5 mg/g for acetylsalicylic acid after Fe3O4 modification. Fast adsorption resulted in equilibrium within 5 min. MBC has potential as a low cost, green adsorbent for pharmaceutical mitigation from water with high adsorption capacities and fast kinetics. The Douglas fir biochar is a byproduct waste from a syn-gas from wood production process covering its production costs.


Assuntos
Carvão Vegetal , Compostos Férricos/química , Magnetismo , Preparações Farmacêuticas/isolamento & purificação , Águas Residuárias/química , Purificação da Água/métodos , Adsorção , Cinética , Pseudotsuga , Poluentes Químicos da Água/isolamento & purificação
8.
J Chromatogr A ; 1621: 461053, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32276857

RESUMO

The chromatographic properties of a new coated amylose tris(3-chloro-5-methylphenylcarbamate) were evaluated in supercritical fluid chromatography for the separation of enantiomers of chiral 1-aryl-5-aryl-pyrrolidin-2-one derivatives, potential anticancer agents, and some commercial drugs. The mobile phase consisted of CO2-modifier mixtures with 30% of either methanol or ethanol, the flow rate was 3 mL/min. The column oven temperature was 40 °C and the outlet pressure was 15 MPa, in order to limit the compressibility of the CO2, thus limiting density variation along the column. The obtained results were then compared to those observed toward 3 other stationary phases: the coated amylose tris(3,5-dimethylphenylcarbamate), the immobilized amylose tris(3,5-dimethylphenylcarbamate) and the coated amylose tris(5-chloro-2-methylphenylcarbamate). It was shown that the new coated amylose tris(3-chloro-5-methylphenylcarbamate) was the most retentive column whatever the studied compounds, particularly for thalidomide and omeprazole with retention factors up to 73.3 and 29.5for the second enantiomer, respectively. Concerning the enantioselectivity, even most of the compounds are separated on all the four columns, the coated amylose tris(3-chloro-5-methylphenylcarbamate) allows the best resolution for most of the ten studied analytes (except omeprazole for which the resolution values are equal to 7.8 and 9.7 on the coated amylose tris(3-chloro-5-methylphenylcarbamate) and amylose tris(3,5-dimethylphenylcarbamate), respectively). Acting in complementary ways, the two chlorinated stationary phases permitted the complete separation of enantiomers of nine compounds out of the ten.


Assuntos
Amilose/análogos & derivados , Cromatografia com Fluido Supercrítico/métodos , Amilose/química , Antineoplásicos/análise , Antineoplásicos/isolamento & purificação , Carbamatos/química , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/isolamento & purificação , Fenilcarbamatos/química , Pirrolidinonas/análise , Pirrolidinonas/isolamento & purificação , Dióxido de Silício/química , Estereoisomerismo
9.
Anal Chim Acta ; 1101: 199-210, 2020 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-32029112

RESUMO

A robust, portable and miniature battery powered gradient capillary liquid chromatograph (total weight ∼2.7 kg, without battery ∼2.0 kg), with integrated microfluidic injection, column heating and high sensitivity low-UV absorbance detection is presented. The portable capillary chromatograph, was applied with a packed reversed-phase capillary column (100 mm × 300 µm I.D., 5 µm ODS), housed within an integrated capillary column heater controlled by a proportional-integral-derivative (PID) chip module. The system delivered retention time and peak area relative standard deviation in isocratic mode of <0.7% (n = 10) and <3.3% (n = 10), respectively, and <0.1% (n = 10) and <2.3% (n = 10) respectively, for gradient elution mode. Detection was based upon a 255 nm light-emitting diode (LED) using one of two commercial capillary flow-cell options, namely a high sensitivity 12 nL Agilent capillary z-cell (HSDC) and a 45 nL Thermo Fisher Scientific UZ-View™ flow cell (UZFC). The HSDC, housed within a 3D printed detector arrangement, gave an effective pathlength of 1.01 mm (84% of nominal pathlength) and stray light of only 0.2%. Limits of detection for four test small molecule pharmaceuticals ranged from 65 to 101 µg L-1 based upon a 316 nL injection volume, with separation efficiencies of between 18,000 and 29,700 N m-1, with sub-4 min run times. The portable capillary LC system was successfully coupled to a small footprint portable mass spectrometer (Microsaic 4500 MiD) to demonstrate compatibility and 'point-of-need' miniaturised LC-MS capability.


Assuntos
Cromatografia Líquida/instrumentação , Cromatografia Líquida/métodos , Fontes de Energia Elétrica , Limite de Detecção , Espectrometria de Massas , Preparações Farmacêuticas/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Espectrofotometria Ultravioleta
10.
J Chromatogr A ; 1618: 460866, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-31964513

RESUMO

An energy-efficient and environment-friendly approach to prepare porous monodispersed micro-sized silica particles with methyltrimethoxysilane (MTMS) as the precursor is described. The particles were synthesized by a two-step hydrolysis/condensation procedure, with post-synthetic aging and calcination for methyl group removal. They show uniform spherical morphology, narrow particle size distribution (D90/10, 1.2-1.6), tailored particle size (3, 5, 7 µm) and mesopore structure (10, 13 nm), which can be directly used as packing materials for HPLC without size classification. C18, sulfonate, and C18/sulfonate mixed-mode stationary phases were produced by a green vapor deposition method based on the synthesized silica particles. The newly synthesized C18 phase exhibits mechanical stability, kinetic behavior and separation performance expected from the commercial C18 column. The C18/sulfonate phase exhibits prominent mixed-mode retention behavior which can be applied to the simultaneous separation of multiple substances in the compound drugs.


Assuntos
Cromatografia Líquida de Alta Pressão , Preparações Farmacêuticas/análise , Dióxido de Silício/química , Hidrólise , Tamanho da Partícula , Preparações Farmacêuticas/isolamento & purificação , Porosidade , Silanos/química , Dióxido de Silício/síntese química
11.
Artigo em Inglês | MEDLINE | ID: mdl-31973074

RESUMO

In this study, we analyzed 27 pharmaceuticals in liquid and solid phase samples collected from the unit processes of four different sewage treatment plants (STPs) to evaluate their distribution and behavior of the pharmaceuticals. The examination of the relative distributions of various categories of pharmaceuticals in the influent showed that non-steroidal anti-inflammatory drugs (NSAIDs) were the most dominant. While the relative distribution of antibiotics in the influent was not high (i.e., 3%-5%), it increased to 14%-30% in the effluent. In the four STPs, the mass load of the target pharmaceuticals was reduced by 88%-95% mainly in the biological treatment process, whereas the ratio of pharmaceuticals in waste sludge to those in the influent (w/w) was only 2%. In all the STPs, the removal efficiencies for the stimulant caffeine, NSAIDs (acetaminophen, naproxen, and acetylsalicylic acid), and the antibiotic cefradine were high; they were removed mainly by biological processes. Certain compounds, such as the NSAID ketoprofen, contrast agent iopromide, lipid regulator gemfibrozil, and antibiotic sulfamethoxazole, showed varying removal efficiencies depending on the contribution of biodegradation and sludge sorption. In addition, a quantitative meta-analysis was performed to compare the pharmaceutical removal efficiencies of the biological treatment processes in the four STPs, which were a membrane bioreactor (MBR) process, sequencing batch reactor (SBR) process, anaerobic-anoxic-oxic (A2O) process, and moving-bed biofilm reactor (MBBR) process. Among the biological processes, the removal efficiency was in the order of MBR > SBR > A2O > MBBR. Among the tertiary treatment processes investigated, powdered activated carbon showed the highest removal efficiency of 18%-63% for gemfibrozil, ibuprofen, ketoprofen, atenolol, cimetidine, and trimethoprim.


Assuntos
Preparações Farmacêuticas/isolamento & purificação , Esgotos , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/isolamento & purificação , Anti-Inflamatórios não Esteroides/isolamento & purificação , Biodegradação Ambiental , Biofilmes , Reatores Biológicos
12.
Anal Bioanal Chem ; 412(1): 113-127, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31897565

RESUMO

Two solid-phase extraction methods were systematically studied to determine 32 pharmaceuticals and personal care products in water and sediments by ultrahigh-performance liquid chromatography-tandem mass spectrometry. One involves HLB cartridges activated with sodium dodecyl sulfate before the passage of the sample to form an ion pair with cationic analytes, and the other uses mixed HLB-cation exchange cartridges. The accuracy of the sodium dodecyl sulfate method was good for most compounds (recoveries of 61-120% with relative standard deviation less than 23%). However, the recoveries for atorvastatin, codeine, paracetamol, flufenamic acid, and salicylic acid were approximately 50% and for omeprazole and triclocarban were even lower (from 0 to 12%). The detection limits were 1.65-25 ng L-1 in water and 0.33-4.00 ng g-1 (dry weight) in sediment. The recoveries for the mixed-mode cartridge (Strata-X-CW) method ranged from 57% to 120% with relative standard deviation less than 21%, with the exception of codeine [25% (water)], metformin [11% (sediment)], paracetamol [48% (sediment)], and salicylic acid [32% (sediment)]. The detection limits were 1.65-38.35 ng L-1 in water and 0.33-10 ng g-1 (dry weight) in sediment. Both methods followed the same pattern when applied to water. For sediments, the recoveries, which offer good performance, were not very high, although 60% of the compounds had recoveries greater 80%. The methods were applied to the analysis of surface water and sediments from the Albufera Natural Park (Spain). Twenty-seven of 32 analytes were detected in the samples analyzed.


Assuntos
Cromatografia Líquida/métodos , Cosméticos/análise , Sedimentos Geológicos/química , Preparações Farmacêuticas/isolamento & purificação , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise , Limite de Detecção , Reprodutibilidade dos Testes , Extração em Fase Sólida/métodos
13.
Sci Total Environ ; 707: 135901, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31972906

RESUMO

Biofilters, similar to those already used for, e.g., removing particles from stormwater and combined sewer overflow can remove organic micropollutants from polluted waters. This study investigated the effects on removal of pharmaceuticals with pulse loadings of increased amounts of pre-settled raw wastewater to four individual biofilters containing different materials (sand, filtralite, stonewool, and sand amended with 1% peat). The effect of increasing BOD concentration to the removal rate constants could be divided into two groups; 1) compounds influenced by increasing loading of BOD: atenolol, propranolol, venlafaxine, citalopram, metoprolol, iohexol, and diclofenac 2) compounds only little or not influenced by increasing concentration of BOD: sulfamethoxazole, sulfamethizole, trimethoprim, iomeprol, and carbamazepine. Though BOD clearly had effects on the degradation, no indications towards a complete stop of the degradation were observed under any circumstances. The different biofilter materials influenced (indirectly) the removal of micropollutants: While the overall best performance was seen in the filtralite biofilter, the stonewool biofilter generally had the lowest removal rate constants. Furthermore, we observed different metabolic pathways of metoprolol in the four different biofilters under formation (and removal) of metoprolol acid, α-hydroxymetoprolol, and O-desmethylmetoprolol.


Assuntos
Carbono , Filtração/métodos , Preparações Farmacêuticas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Análise da Demanda Biológica de Oxigênio , Águas Residuárias
14.
J Chromatogr A ; 1614: 460702, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31740032

RESUMO

A stilbene diamido-bridged bis(ß-cyclodextrin) was synthesized via the reaction between 4,4'-stilbene dicarboxylic acid and 6-deoxy-6-amino-ß-cyclodextrin. Then it was bonded onto the surface of an ordered mesoporous SBA-15 to obtain a novel bridged bis(ß-cyclodextrin)-bonded chiral stationary phase (SBCDP). The structures of the bridged bis(ß-cyclodextrin) and SBCDP were characterized by the mass spectrometry, nuclear magnetic resonance, infrared spectroscopy, elemental analysis and thermogravimetric analysis. The chromatographic performance of SBCDP was systematically evaluated by separating 23 racemic drugs and pesticides, including trimeprazine, praziquantel, flavanones, ß-blockers and triazole pesticides in the reversed-phase chromatography or the polar organic mode. The chromatographic conditions that affect the enantioselectivity or diasterioselectivity of SBCDP were investigated in detail, including the mobile phase composition, pH value and column temperature. As a result, all tested analytes were resolved on SBCDP with high resolutions (1.51∼5.15) within about 25 min, and the enantioseparation resolutions of flavanone and imazalil were up to 5.15 and 4.38, respectively. Compared with the native ß-cyclodextrin stationary phase (CDCSP), the SBCDP had a better chromatographic performance in enantioselectivity and diasterioselectivity. For example, enantiomers of trimeprazine, praziquantel, flavanone and imazalil those could not be separated by CDCSP, were separated by SBCDP with high resolutions. Unlike the small cavity (0.65 nm) of native CD, the bridging linker of the bridged bis(ß-CD) supplied a well-organized "pseudo-cavity", and combined two native CDs as an organic whole, which could synergistically encapsulate and complex some bulky analytes, making the chiral discrimination of SBCDP more precise. Moreover, we also found that SBCDP possessed high enantioselectivity and diastereoselectivity over a wide range of temperature (30∼60 °C), which made the fast analysis possible. As a new chiral separation material, SBCDP may have wider applications in analysis of chiral compounds.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Praguicidas/análise , Preparações Farmacêuticas/análise , Estilbenos/química , Concentração de Íons de Hidrogênio , Praguicidas/isolamento & purificação , Preparações Farmacêuticas/isolamento & purificação , Porosidade , Dióxido de Silício/química , Estereoisomerismo , beta-Ciclodextrinas/química
15.
Chemosphere ; 238: 124658, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31548174

RESUMO

Adsorption is a common process used to remove pharmaceuticals, personal care products and endocrine disrupting chemicals (PPCPs/EDCs) from water. However, as PPCPs/EDCs cover a wide range of molecules and chemical structures, prediction of the adsorption capacity is very challenging. In this study, a novel model was developed to predict adsorption isotherms of PPCPs/EDCs onto various types of adsorbents using a combination of Polanyi potential theory, molecular connectivity indices (MCIs) and molecular characteristics. Polanyi theory provided the basic mathematical form for the correlation. MCIs, hydrophobicity and H-bond count were used to normalize the Polanyi equation based on the molecular structure and interactions among the chemicals, the adsorbents, and the solution. In total, adsorption data were collected from 158 reports for 55 PPCPs/EDCs onto 306 different adsorbent materials. The correlation was first trained with 46 PPCPs/EDCs adsorbed onto 162 carbonaceous adsorbents (CAs), with 44.8% SDEV. Then the model was employed to predict 46 PPCPs/EDCs onto 118 other CAs and 9 new PPCPs/EDCs onto 23 CAs in ultrapure water, with error from 42 to 48% SDEV. When applying to non-carbonaceous adsorbents, the models can still predict the adsorption of PPCPs/EDCs with 90.09% SDEV. For the first time, a model, the PD - MCI - hydrophobic - H bond model, was developed to predict adsorption of a wide group of complicated PPCPs/EDCs onto a big variety of carbonaceous and non-carbonaceous adsorbents. The proposed model approach may provide a simple means for predicting adsorption capacities of PPCPs/EDCs onto various adsorbents.


Assuntos
Cosméticos/isolamento & purificação , Disruptores Endócrinos/isolamento & purificação , Preparações Farmacêuticas/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Disruptores Endócrinos/análise , Interações Hidrofóbicas e Hidrofílicas , Água/química , Poluentes Químicos da Água/análise
16.
Anal Sci ; 35(12): 1385-1391, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827038

RESUMO

This study deals with the application of different monoterpenes as relatively green bio-based solvents for low density-dispersive liquid-liquid microextraction (LD-DLLME) of different non-steroidal anti-inflammatory drugs (NSAIDs) from aqueous samples in comparison with conventional halogenated solvents. Results indicated that D-limonene could extract the hydrophobic compounds with higher %recovery compared with other bio-based and halogenated solvents. The LD-DLLME procedure was optimized by applying one-factor-at-a-time (OFAT) followed by central composite face-centered design (CCF) of the response surface methodology (RSM). Under the optimal conditions, the method exhibited good linearity with r ≥ 0.9950 with low LOD as well as LOQ levels in the range of 0.11 to 0.81 and 0.36 to 2.69 ng/mL, respectively. The method was efficiently applied to a variety of real aqueous samples. Finally, the green aspect of our procedure was compared with some reported methods using two green metric tools.


Assuntos
Limoneno/química , Microextração em Fase Líquida/métodos , Preparações Farmacêuticas/isolamento & purificação , Solventes/química , Poluentes Químicos da Água/isolamento & purificação , Água/química , Concentração de Íons de Hidrogênio , Limite de Detecção , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química
17.
Molecules ; 25(1)2019 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-31881683

RESUMO

In the present work, the effectiveness of switchable hydrophobicity solvents (SHSs) as extraction solvent (N,N-Dimethylcyclohexylamine (DMCA), N,N-Diethylethanamine (TEA), and N,N-Benzyldimethylamine (DMBA)) for a variety of emerging pollutants was evaluated. Different pharmaceutical products (nonsteroidal anti-inflammatory drugs (NSAIDs), hormones, and triclosan) were selected as target analytes, covering a range of hydrophobicity (LogP) of 3.1 to 5.2. The optimized procedure was used for the determination of the target pharmaceutical analytes in wastewater samples as model analytical problem. Absolute extraction recoveries were in the range of 51% to 103%. The presented method permits the determination of the target analytes at the low ng mL-1 level, ranging from 0.8 to 5.9 (except for Triclosan, 106 ng mL-1) with good precision (relative standard deviation lower than 6%) using high-pressure liquid chromatography (HPLC) combined with ultraviolet (DAD) and fluorescence (FLR) detection. The microextraction alternative resulted in a fast, simple, and green method for a wide variety of analytes in environmental water sample. The results suggest that this type of solvent turns out to be a great alternative for the determination of different analytes in relatively complex water samples.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Solventes/química , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Cicloexilaminas/química , Preparações Farmacêuticas/isolamento & purificação , Hidróxido de Sódio/química , Extração em Fase Sólida
18.
Molecules ; 24(21)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683674

RESUMO

Deep-sea natural products have been created by unique marine organisms that thrive in a challenging environment of extreme conditions for its inhabitants. In this study, 179 deep-sea natural products isolated from 2009 to 2013 were investigated by analysing their physicochemical properties that are important indicators of the ADMET (Absorption, Distribution, Metabolism, Excretion and Toxicity) profile of a compound. The study and analysis of these molecular descriptors and characteristics enabled the defining of these compounds in various chemical spaces, particularly as an indication of their drug-likeness and position in chemical space and is the first to be conducted to analyse deep-sea derived natural products. It was found that ~40% of all deep-sea natural products were drug-like and 2/3 were within Known Drug Space (KDS), highlighting the high drug-likeness of a significant proportion of deep-sea natural products, most of which have already been shown to have notable biological activities, that should be further investigated as potential therapeutics. Furthermore, this study was able to reveal the general structural differences between compounds from Animalia, Bacteria and Fungi organisms where it was observed that natural products from members of the Animalia kingdom are structurally more varied than compounds from bacteria and fungi. It was also noted that, in general, fungi-derived compounds occupy a more favourable position in drug-like chemical space and are a rich and promising source of biologically-active natural products for the purposes of drug development and therapeutic application.


Assuntos
Organismos Aquáticos/química , Produtos Biológicos/química , 1-Octanol/química , Animais , Bactérias/química , Produtos Biológicos/isolamento & purificação , Fungos/química , Ligação de Hidrogênio , Peso Molecular , Preparações Farmacêuticas/química , Preparações Farmacêuticas/isolamento & purificação , Filogenia , Análise de Componente Principal , Água/química
19.
ACS Appl Mater Interfaces ; 11(40): 37163-37171, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31545586

RESUMO

Membrane performance in separation relies largely on the membrane properties. In this study, metal ions of Cu2+, Co2+, and Fe3+ are used individually as a bridge to develop forward osmosis (FO) membranes via a clean complexation reaction. A metal ion-bridged hydration layer is formed and endows the membrane with a more hydrophilic and smoother surface, higher fouling resistance, and renewability. These improvements make the newly developed membranes superior to the pristine one with better FO performances. The Fe3+-bridged membrane produces water fluxes increased up to 133% (FO mode) and 101% (PRO mode) compared with the pristine membrane against DI water with 0.5-2.0 M MgCl2 as the draw solution. The Fe3+-bridged membrane can efficiently reclaim pharmaceuticals such as trimethoprim and sulfamethoxazole from their dilute solutions with good water permeability and a high pharmaceutical retention. This membrane also exhibits a stronger renewability with water flux restored to 98% of its original value after 20 h experiments in trimethoprim-containing water treatment. This study provides a facile and clean approach to develop highly efficient FO membranes for wastewater reclamation and pharmaceutical enrichment.


Assuntos
Membranas Artificiais , Metais/química , Osmose , Preparações Farmacêuticas/isolamento & purificação , Águas Residuárias/química , Purificação da Água/métodos , Íons , Espectroscopia Fotoeletrônica , Espectroscopia de Infravermelho com Transformada de Fourier , Fatores de Tempo
20.
J Pharm Biomed Anal ; 176: 112794, 2019 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31437749

RESUMO

The drive for faster separations while maintaining quality and yield remains an important consideration for enhanced productivity as well as cost reduction for drug discovery laboratories in the pharmaceutical industry. High-throughput experimentation (HTE) and high-throughput screening (HTS) techniques can benefit from rapid and efficient isolation of product at high purity and recovery from microgram-scale crude reaction mixtures. In this study we describe the isolation of small molecule and biomolecule crude mixtures at the microgram-scale (100-2500 µg) in single or library format with methods as fast as 1.0 min and system pressures averaging 10,000 psi with an ultra-high pressure liquid chromatography (UHPLC) setup. UHPLC technology provides several advantages for rapid (<1.0 min) separations with small-particle (1.8-3.5 µm) size 4.6 × 50 mm C18 columns such as minimal extra column and delay volume, fast detector response time, and higher linear velocities for improved speed and resolution. We typically see a 5-10 fold improvement in purification time and overall sample processing time with low fraction volumes and same-day drying when compared with traditional semi-preparative techniques. There is a significant 50-fold reduction in solvent usage per run, resulting in a much lower cost of solvent and waste handling. Fluidic pathways have been optimized for collection into tared high-density 96 or 384 well 2D barcoded storage tubes in a microtiter plate (MTP) layout. Coupling the system to robotics has enabled us to implement a fully integrated automation platform with additional capabilities for small-scale purification at high speed and reduced cost of materials. The resulting arrays of small-quantity, high-purity compounds enable synthetic route scouting for HTE and HTS for biological target validation.


Assuntos
Descoberta de Drogas/métodos , Técnicas Analíticas Microfluídicas/métodos , Preparações Farmacêuticas/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Fatores de Tempo
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