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1.
Vaccimonitor (La Habana, Print) ; 29(1)ene.-abr. 2020. graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1094635

RESUMO

En este trabajo se presenta la aplicación del Análisis de Componentes Principales, mediante el programa THE UNSCRAMBLER versión 8.0, a los datos registrados en un período de 2 años en la etapa de purificación de una planta de producción de Eritropoyetina Humana Recombinante que está basada en varios pasos cromatográficos, de forma similar a los procesos de purificación de proteínas recombinantes que se utilizan como vacunas preventivas o terapéuticas. Se logró reducir dimensionalidad al obtenerse dos componentes principales que explican el 81 por ciento de la varianza de 18 variables originales relacionadas con cuatro pasos cromatográficos. Como resultado se llegó a definir cuáles son las variables que mayor aporte tienen a la variabilidad del proceso en la etapa de purificación, permitiendo extraer información útil para lograr un mayor entendimiento del proceso y enriquecer las estrategias de control en la planta. Dichos resultados corroboraron experiencias prácticas de especialistas de la planta y permitieron dar recomendaciones a considerar en el plan de verificación continuada del proceso como proponer cinco variables como controles de proceso y tener en cuenta que el rendimiento del segundo paso cromatográfico es el más influyente de los rendimientos considerados en la variabilidad(AU)


This paper presents the application of the Principal Component Analysis, using the program THE UNSCRAMBLER version 8.0, to the data recorded during two years in the purification stage of a Recombinant Human Erythropoietin plant that is based on several chromatographic steps, similar to the purification process of recombinant proteins that are used as preventive or therapeutic vaccines. Dimensionality was reduced by obtaining two main components that explain 81 percent of the variance of 18 original variables related to four chromatographic steps. As a result, it was possible to define which variables have the greatest contribution to the variability of the process in the purification stage, allowing to extract useful information to achieve a greater understanding of the process and enrich the control strategies in the plant. These results corroborated practical experiences of plant specialists and allowed for recommendations to be considered in the continuous verification plan of the process, such as proposing three variables as process controls and taking into account that the performance of the second step is the most influential of the performances considered in the variability(AU)


Assuntos
Produtos Biológicos/uso terapêutico , Cromatografia/métodos , Análise de Componente Principal/métodos , Medicamentos de Referência , Biofarmácia
2.
PLoS One ; 15(2): e0228989, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32053695

RESUMO

Prediction and early detection of kidney damage induced by nonsteroidal anti-inflammatories (NSAIDs) would provide the best chances of maximizing the anti-inflammatory effects while minimizing the risk of kidney damage. Unfortunately, biomarkers for detecting NSAID-induced kidney damage in cats remain to be discovered. To identify potential urinary biomarkers for monitoring NSAID-based treatments, we applied an untargeted metabolomics approach to urine collected from cats treated repeatedly with meloxicam or saline for up to 17 days. Applying multivariate analysis, this study identified a panel of seven metabolites that discriminate meloxicam treated from saline treated cats. Combining artificial intelligence machine learning algorithms and an independent testing urinary metabolome data set from cats with meloxicam-induced kidney damage, a panel of metabolites was identified and validated. The panel of metabolites including tryptophan, tyrosine, taurine, threonic acid, pseudouridine, xylitol and lyxitol, successfully distinguish meloxicam-treated and saline-treated cats with up to 75-100% sensitivity and specificity. This panel of urinary metabolites may prove a useful and non-invasive diagnostic tool for monitoring potential NSAID induced kidney injury in feline patients and may act as the framework for identifying urine biomarkers of NSAID induced injury in other species.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Biomarcadores/urina , Animais , Anti-Inflamatórios não Esteroides/urina , Inteligência Artificial , Butiratos/urina , Gatos , Cromatografia , Análise por Conglomerados , Feminino , Humanos , Espectrometria de Massas , Metabolômica/métodos , Pseudouridina/urina , Curva ROC , Álcoois Açúcares/urina , Taurina/urina , Tirosina/urina , Xilitol/urina
3.
Biomed Chromatogr ; 34(3): e4798, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31994210

RESUMO

Chromatographic method has long been recognized as the most widely used separation method in bioanalytical research. However, the relatively low sensitivity of existing chromatographic methods remains a significant challenge, as the requirements for experimental procedures become more demanding. This review discusses the main causes for the low sensitivity of chromatographic methods and aims to introduce different technologies for enhancing their sensitivity in the following aspects: (i) different pretreatment methods for improving clean-up efficiency and recovery; (ii) derivatization step for altering the chromatographic behavior of analytes and enhancing MS ionization efficiency; (iii) optimal LC-MS conditions and appropriate separation mechanism; and (iv) applications of other chromatographic methods, including miniaturized LC, 2D-LC, 2D-GC, and supercritical fluid chromatography. Altogether, this review is devoted to summarizing the recent technologies reported in the literature and providing new strategies for the detection of bioanalytes.


Assuntos
Cromatografia/métodos , Animais , Ácidos Graxos/análise , Humanos , Espectrometria de Massas , Camundongos , Preparações Farmacêuticas/análise , Sensibilidade e Especificidade , Esteroides/análise
4.
Mol Immunol ; 119: 27-34, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31955064

RESUMO

Mutations in Factor XII, plasminogen gene, angiopoietin-1 gene and kininogen 1 gene have been found in some patients with hereditary angioedema with normal C1 inhibitor (HAE-nl-C1inh), but the underlying disease mechanisms remain unclear. Additionally, there are no accepted biomarkers for this disease. Because the contact system has been implicated in hereditary angioedema with C1 inhibitor deficiency (HAE-C1inh), we studied the fragmentation patterns of serum glycoprotein 120 (sgp120), a protein that is highly susceptible to cleavage by kallikrein, in 31 HAE-C1inh and 13 HAE-nl-C1inh patient plasma samples. Compared to normal controls, the majority of plasma samples from patients with HAE-C1inh contained fragmented sgp120. These samples also showed increased kallikrein amidolytic activity indicating spontaneous contact system activation. In contrast, most samples from HAE-nl-C1inh patients exhibited intact sgp120. However, if these samples were incubated at 4 °C in plastic, significant sgp120 fragmentation and spontaneous contact system activation were observed. Concurrently, there was C1 inhibitor fragmentation that generated the nonfunctional 94 kD fragment and a reduction in C1 inhibitor function. Normal samples did not show sgp120 or C1 inhibitor fragmentation after incubation. We sequenced sgp120 and found it to be identical to inter-alpha-trypsin inhibitor heavy chain 4 (ITIH4). These results suggest that sgp120 or ITIH4 is cleaved when the contact system is activated and that this cleavage could be used as a biomarker in patients with HAE-nl-C1inh.


Assuntos
Angioedemas Hereditários/sangue , Angioedemas Hereditários/diagnóstico , Proteína Inibidora do Complemento C1/metabolismo , Proteínas Secretadas Inibidoras de Proteinases/sangue , Angioedemas Hereditários/genética , Biomarcadores/sangue , Fatores de Coagulação Sanguínea/metabolismo , Cromatografia/métodos , Ativação do Complemento , Fator XII/genética , Humanos , Calicreínas/metabolismo , Caulim/metabolismo , Fragmentos de Peptídeos/sangue , Plasminogênio/genética , Plásticos , Proteólise
5.
J Chromatogr A ; 1609: 460446, 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31420178

RESUMO

Two new copolymer-grafted silica stationary phases were prepared and employed in hydrophilic interaction chromatography (HILIC). 2-(Dimethylamino)ethyl methacrylate (DMAEMA) are copolymerized with itaconic acid (IA) and acrylic acid (AA) respectively, via thiol-ene click reaction on silica surface with deep eutectic solvents (DES) as new solvents. The obtained poly(DMAEMA-co-itaconic acid)-grafted silica (Sil-PDM-PIA) and poly(DMAEMA-co-acrylic acid)-grafted silica (Sil-PDM-PAA) were characterized by Fourier transform infrared spectroscopy, elemental analysis and solid-state 13C NMR spectra. Their hydrophilic interaction performances were evaluated by separating nucleosides, nucleobases, saccharides, and amino acids. Compared with previous reported poly(itaconic acid)-grafted silica (Sil-PIA) and poly(acrylic acid)-grafted silica (Sil-PAA) stationary phases, these two new copolymer-grafted silica performed higher selectivity and better separation for polar analytes in HILIC.


Assuntos
Cromatografia/métodos , Química Click/métodos , Interações Hidrofóbicas e Hidrofílicas , Polímeros/química , Dióxido de Silício/química , Solventes/química , Compostos de Sulfidrila/química , Acetonitrilos/química , Aminoácidos/isolamento & purificação , Entropia , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Metacrilatos/química , Nucleosídeos/isolamento & purificação , Nylons/química , Reprodutibilidade dos Testes , Sais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Succinatos/química , Temperatura
6.
Food Chem ; 306: 125595, 2020 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-31610324

RESUMO

Assessing the authenticity of honey is a serious problem that has gained much interest internationally because honey has frequently been subject to various fraudulent practices, including mislabelling of botanical and geographical origin and mixing with sugar syrups or honey of lower quality. To protect the health of consumers and avoid competition, which could create an unstable market, consumers, beekeepers and regulatory bodies are interested in having reliable analytical methodologies to detect non-compliant honey. This paper gives an overview of the different approaches used to assess the authenticity of honey, specifically by the application of advanced instrumental techniques, including spectrometric, spectroscopic and chromatographic methods coupled with chemometric interpretation of the data. Recent development in honey analysis and application of the honey authentication process in the Romanian context are highlighted, and future trends in the process of detecting and eliminating fraudulent practices in honey production are discussed.


Assuntos
Mel/análise , Carboidratos/análise , Cromatografia , Contaminação de Alimentos/análise , Romênia , Análise Espectral
7.
Biomed Chromatogr ; 34(1): e4764, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31884691
8.
Talanta ; 206: 120248, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31514863

RESUMO

Metabolomics generate a profile of small molecules from plant extracts, which could be directly responsible for bioactivity effects. Using dry-column flash chromatography enabled a rapid and inexpensive method for the very efficient separation of plant extract with a high resolution. This separation method coupled to NMR and FTIR-based metabolomics is applied to identify bioactive natural products. OPLS multivariate analysis method, was used for correlation the chemical composition of the plant extracts, Amphoricarpos autariatus, with the results of cytotoxic activity against Human cervical adenocarcinoma cell line (HeLa) and epithelial lung cancer cell line (A549). In this way, the highest contribution to the cytotoxic activity was recorded for the guaianolide sesquiterpene lactones named amphoricarpolides. The compounds indicated as bioactive after metabolomics analysis were tested, and their cytotoxic activity were confirmed.


Assuntos
Asteraceae/química , Citotoxinas/análise , Lactonas/análise , Metabolômica/métodos , Sesquiterpenos de Guaiano/análise , Linhagem Celular Tumoral , Cromatografia , Citotoxinas/isolamento & purificação , Citotoxinas/toxicidade , Humanos , Lactonas/isolamento & purificação , Lactonas/toxicidade , Espectroscopia de Ressonância Magnética , Componentes Aéreos da Planta/química , Sesquiterpenos de Guaiano/isolamento & purificação , Sesquiterpenos de Guaiano/toxicidade , Espectroscopia de Infravermelho com Transformada de Fourier
9.
J Environ Radioact ; 211: 106083, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31707256

RESUMO

The efficient extraction of small quantities of 210Po is necessary for preparing 210Po standard reference materials. Herein, a commercially available strontrium-specific chromatographic resin (Sr spec resin) was used to rapidly and selectively extract 210Po from a 210Pb-210Bi-210Po mixture, and the distribution ratios of Pb, Bi, and 210Po on Sr spec resin were probed using batch experiments. In contrast to 210Pb and 210Bi, 210Po was retained on the Sr spec cartridge in 8 M HCl and was then effectively eluted by 0.1 M HNO3. The contents of 210Pb and 210Bi in the thus obtained 210Po solution were checked using a high purity germanium gamma-ray detector and the corresponding decay curve, respectively, and were found not to exceed 2%. Moreover, the 210Pb and 210Bi eluates could be used to regenerate 210Po by the same method after a certain time period. Therefore, the extracted 210Po solution was suitable for the preparation of the 210Po standard area source and 210Po standard reference materials.


Assuntos
Cromatografia , Radioisótopos de Chumbo , Polônio , Monitoramento de Radiação , Estrôncio
10.
J Pharm Biomed Anal ; 177: 112867, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31614303

RESUMO

Gut microbiota, the specific microbial community of the gastrointestinal tract, by means of the production of microbial metabolites provides the host with several functions affecting metabolic and immunological homeostasis. Insights into the intricate relationships between gut microbiota and the host require not only the understanding of its structure and function but also the measurement of effector molecules acting along the gut microbiota axis. This article reviews the literature on targeted chromatographic approaches in analysis of gut microbiota specific metabolites in feces as the most accessible biological matrix which can directly probe the connection between intestinal bacteria and the (patho)physiology of the holobiont. Together with a discussion on sample collection and preparation, the chromatographic methods targeted to determination of some classes of microbiota-derived metabolites (e.g., short-chain fatty acids, bile acids, low molecular masses amines and polyamines, vitamins, neurotransmitters and related compounds) are discussed and their main characteristics, summarized in Tables.


Assuntos
Fezes/química , Microbioma Gastrointestinal/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Metabolômica/métodos , Manejo de Espécimes/métodos , Ácidos e Sais Biliares/análise , Ácidos e Sais Biliares/metabolismo , Cromatografia/métodos , Ácidos Graxos Voláteis/análise , Ácidos Graxos Voláteis/metabolismo , Humanos , Espectrometria de Massas/métodos , Neurotransmissores/análise , Neurotransmissores/metabolismo , Poliaminas/análise , Poliaminas/metabolismo , Vitaminas/análise , Vitaminas/metabolismo
11.
Clin Lab ; 65(12)2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31850714

RESUMO

BACKGROUND: Viral gastroenteritis is one of the most common illnesses in humans worldwide, and different viral agents have been shown to be associated with the disease. Among these, rotaviruses and adenoviruses are the responsible causative agents of acute gastroenteritis and causing numerous outbreaks. Therefore, a simple and rapid diagnostic tool, such as an immunochromatographic (IC) test, is required for rapid diagnosis, especially during an outbreak of these pathogens. METHODS: The efficiency of two commercial IC kits were evaluated for simultaneous detections of rotavirus and adenovirus in clinical stool specimens by a single test kit. RESULTS: The data demonstrated that both IC test kits could detect either adenovirus or rotavirus positive alone, as well as mixed infections of both viruses in a single stool specimen. In addition, a wide variety of rotavirus genotypes, including G1-P[8]-I1, G2-P[4]-I2, G3-P[8]-I2, G8-P[8]-I2, and G9-P[8]-I1 could be detected by both IC kits. The detection limit of the kits for the detection of rotavirus and adenovirus were comparable to those of real-time PCR at 105 copies/mL. CONCLUSIONS: These two IC test kits could be used as an alternative choice for rapid screening of rotavirus and adenovirus in the stool specimens, especially during the seasonal outbreak of acute gastroenteritis.


Assuntos
Infecções por Adenoviridae/diagnóstico , Adenoviridae/genética , Cromatografia/métodos , Imunoensaio/métodos , Infecções por Rotavirus/diagnóstico , Rotavirus/genética , Adenoviridae/fisiologia , Infecções por Adenoviridae/complicações , Infecções por Adenoviridae/virologia , Pré-Escolar , Fezes/virologia , Gastroenterite/complicações , Gastroenterite/diagnóstico , Genótipo , Humanos , Lactente , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Rotavirus/fisiologia , Infecções por Rotavirus/complicações , Infecções por Rotavirus/virologia , Sensibilidade e Especificidade
12.
Harmful Algae ; 89: 101666, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31672231

RESUMO

Harmful algal blooms caused by Chattonella marina recently have caused severe negative effect on coastal economy worldwide, with increased occurrence frequency and scale. It is therefore vital to establish new methods for rapid detection of this alga. In this study, the internal transcribed spacer (ITS) sequence was used as the target gene for molecular detection of C. marina. First, four loop-mediated isothermal amplification (LAMP) primers were designed based on the six regions of ITS, and the LAMP reaction system was established using these primers. Next, a probe was designed to detect the LAMP products by lateral-flow dipstick (LFD). Finally, a new method for rapid and sensitive detection of C. marina that is referred to as LAMP-LFD was established. The LAMP reaction system, amplification time, and amplification temperature were particularly optimized. The optimal parameters are as follows: Mg2+ concentration, 10 mM;dNTP concentration, 1.2 mM;ratio of internal primer concentration to outer primer concentration, 8:1;reaction time, 60 min;and reaction temperature, 60 °C. Both specificity and sensitivity were tested using the optimized LAMP reaction system in combination with LFD (LAMP-LFD). The established LAMP-LFD displayed good specificity and no cross reaction was detected with non-target algal species. The detection limit of LAMP-LFD was 3.4 × 10-4 ng µL-1 (3.4 × 10-4 ng per reaction) for the genomic DNA of target algae, and 1.3 copies µL-1 (1.3 copies per reaction) for the plasmid DNA containing the target ITS. Sensitivity tests using genomic DNA and plasmid DNA as templates consistently revealed that LAMP-LFD is 100 times more sensitive than regular PCR. The established LAMP-LFD was applied to analyze the simulated samples and the results showed that the detection limit of LAMP-LFD could reach 1 cell mL-1. LAMP-LFD also demonstrated good specificity and sensitivity in the analysis of natural samples. The whole procedure of LAMP-LFD could be completed within 1.5 h. Taken together, the LAMP-LFD assay developed here is characterized by simplicity, high specificity and sensitivity, and rapidity and therefore is promising for rapid detection of C. marina.


Assuntos
Cromatografia , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade
13.
J Forensic Sci ; 64(6): 1720-1725, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31674674

RESUMO

One of the most important contributions of forensic entomology is to assist criminal expertise to determine the postmortem interval, which depends on the duration of the immature stages of insects of forensic interest. On the other hand, the time of development of the different stages varies according to the species; therefore, its identification is essential. Currently, few studies have investigated the use of cuticular hydrocarbons, and none regarding fatty acids, as complementary taxonomic tools to expedite species identification. Therefore, we evaluated whether cuticular hydrocarbons together with fatty acids of eggs of flies of the family Calliphoridae, main group of forensic interest, can be used to distinguish species. The analyses were performed by chromatographic techniques. The results show that there are significant differences between the composition of cuticular hydrocarbons and fatty acids between species and, therefore, they can be used to provide a complementary taxonomic tool to expedite the forensic expertise.


Assuntos
Dípteros/metabolismo , Ácidos Graxos/metabolismo , Hidrocarbonetos/metabolismo , Óvulo/metabolismo , Escamas de Animais/metabolismo , Animais , Cromatografia , Análise Discriminante , Entomologia/métodos , Ciências Forenses , Especificidade da Espécie
14.
Sud Med Ekspert ; 62(5): 39-42, 2019.
Artigo em Russo | MEDLINE | ID: mdl-31626193

RESUMO

In medical literature there is no single detailed standard for studying the biochemical composition of a tooth. This circumstance led to the development of a proprietary method for determining the enantiomers of aspartic acid in hard dental tissues for use in the further study of the relationship between the amino acid composition of dental tissues and the biological age of humans. Dental tissue samples obtained from living individuals aged from 20 to 50 years were studied by chromatography-mass spectrometry. The results of the study allowed us to put forward a number of practical recommendations on the standardization of the procedure for the preparation of dental tissue samples and the parameters of chromatography-mass spectrometry research.


Assuntos
Determinação da Idade pelos Dentes , Ácido Aspártico/análise , Adulto , Cromatografia , Odontologia Legal , Dureza , Humanos , Espectrometria de Massas , Pessoa de Meia-Idade , Manejo de Espécimes/normas , Adulto Jovem
15.
Mar Drugs ; 17(9)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547415

RESUMO

For the full use of Spanish mackerel (Scomberomorous niphonius) muscle to produce antioxidant peptides, the proteins of Spanish mackerel muscle were separately hydrolyzed under five kinds of enzymes and in vitro gastrointestinal digestion, and antioxidant peptides were isolated from the protein hydrolysate using ultrafiltration and multiple chromatography methods. The results showed that the hydrolysate (SMPH) prepared using in vitro GI digestion showed the highest degree of hydrolysis (27.45 ± 1.76%) and DPPH radical scavenging activity (52.58 ± 2.68%) at the concentration of 10 mg protein/mL among the six protein hydrolysates, and 12 peptides (SMP-1 to SMP-12) were prepared from SMPH. Among them, SMP-3, SMP-7, SMP-10, and SMP-11 showed the higher DPPH radical scavenging activities and were identified as Pro-Glu-Leu-Asp-Trp (PELDW), Trp-Pro-Asp-His-Trp (WPDHW), and Phe-Gly-Tyr-Asp-Trp-Trp (FGYDWW), and Tyr-Leu-His-Phe-Trp (YLHFW), respectively. PELDW, WPDHW, FGYDWW, and YLHFW showed high scavenging activities on DPPH radical (EC50 1.53, 0.70, 0.53, and 0.97 mg/mL, respectively), hydroxyl radical (EC50 1.12, 0.38, 0.26, and 0.67 mg/mL, respectively), and superoxide anion radical (EC50 0.85, 0.49, 0.34, and 1.37 mg/mL, respectively). Moreover, PELDW, WPDHW, FGYDWW, and YLHFW could dose-dependently inhibit lipid peroxidation in the linoleic acid model system and protect plasmid DNA (pBR322DNA) against oxidative damage induced by H2O2 in the tested model systems. In addition, PELDW, WPDHW, FGYDWW, and YLHFW could retain their high activities when they were treated under a low temperature (<60 °C) and a moderate pH environment (pH 5-9). These present results indicate that the protein hydrolysate, fractions, and isolated peptides from Spanish mackerel muscle have strong antioxidant activity and might have the potential to be used in health food products.


Assuntos
Antioxidantes/farmacologia , Produtos Pesqueiros , Peptídeos/farmacologia , Perciformes , Hidrolisados de Proteína/química , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Fracionamento Químico/métodos , Cromatografia/métodos , Peroxidação de Lipídeos/efeitos dos fármacos , Músculos/química , Estresse Oxidativo/efeitos dos fármacos , Peptídeos/química , Peptídeos/isolamento & purificação , Estabilidade Proteica , Ultrafiltração/métodos
16.
Anal Chim Acta ; 1082: 186-193, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472708

RESUMO

Exosomes are one class of extracellular vesicles (30-150 nm diameter) that are secreted by cells. These small vesicles hold a great deal of promise in disease diagnostics, as they display the same protein biomarkers as their originating cell. On a cellular level, exosomes are attributed to playing a key role in intercellular communication, and may eventually be exploited for targeted drug delivery. In order for exosomes to become useful in disease diagnostics, and as burgeoning drug delivery platforms, they must be isolated efficiently and effectively without compromising their structure. Plasma from peripheral blood is an excellent source of exosomes, as it is easily collected and the process does not normally cause undue discomfort to the patient. Unfortunately, blood plasma content is complex, containing abundant amounts of soluble proteins and aggregates, making exosomes extremely difficult to isolate in high purity from plasma. Most current exosome isolation methods have practical challenges including being too time-consuming and labor intensive, destructive to the exosomes, or too costly for use in clinical settings. To this end, this study examines the use of poly(ethylene terephthalate) (PET) capillary-channeled polymer (C-CP) fibers in a hydrophobic interaction chromatography (HIC) protocol to isolate exosomes from a human plasma sample. Initial results demonstrate the ability to isolate exosomes with comparable yields and size distributions and on a much faster time scale when compared to traditional isolation methods, while also alleviating concomitant proteins and other impurities. As a demonstration of the potential quantitative utility of the approach, a linear response (particles injected on-column vs peak area) using a commercial exosome standard was established using a standard UV absorbance detector. Based on the calibration function, the concentration of the original human plasma sample was determined and subsequently confirmed by NTA measurement. The potential for scalable separations covering sub-milliliter spin-down solid phase extraction tips to the preparative scale is anticipated.


Assuntos
Células Sanguíneas , Exossomos , Cromatografia/instrumentação , Cromatografia/métodos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Polietilenotereftalatos/química
17.
Artigo em Inglês | MEDLINE | ID: mdl-31525723
18.
Molecules ; 24(19)2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554326

RESUMO

With the increase in the number of medicines patients have to take, there has been a rapid rise of fixed-dose combinations (FDCs) in the last two decades. Prior to FDC development, pharmacokinetic properties of active pharmaceutical ingredients (APIs) have to be evaluated, as well as methods for their determination developed. So as to increase patient compliance in inflammatory bowel disease, three novel FDCs of thiopurine immunosuppressants and folic acid are proposed; physico-chemical and pharmacokinetic properties such as hydrophobicity, lipophilicity and plasma protein binding of all APIs are evaluated. Moreover, experimental results of different properties are compared to those computed by various on-line prediction platforms so as to evaluate the viability of the in silico approach. A simultaneous method for their determination is developed, optimized, validated and applied to commercial tablet formulations. The method has shown to be fast, selective, accurate and precise, showing potential for reliable determination of API content in proposed FDCs during its development.


Assuntos
Cromatografia , Ácido Fólico/farmacocinética , Imunossupressores/farmacocinética , Fenômenos Químicos , Cromatografia Líquida de Alta Pressão , Ácido Fólico/administração & dosagem , Ácido Fólico/química , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/química , Estrutura Molecular
19.
Yi Chuan ; 41(9): 883-892, 2019 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-31549686

RESUMO

Metabolomics (defined as comprehensive small molecule chemical analysis), together with genomics, transcriptomics, proteomics and phenomics, now plays a fundamental role in system biological studies. Chromatography- mass spectrometry machines, which have the characteristics of high resolution and high sensitivity, are widely used for metabolomics analysis, both qualitatively and quantitatively. With the fast development of the chromatography-mass spectrometry technology, metabolomics analysis has been successfully applied in various biological research fields. Here, we introduce the different chromatography-mass spectrum machines used for metabolomics analysis and their applications to various biological issues by mainly using the metabolomics platform in Institute of Genetics and Developmental Biology as a case study.


Assuntos
Metabolômica/instrumentação , Metabolômica/tendências , Cromatografia , Genômica , Espectrometria de Massas , Proteômica
20.
J Chromatogr A ; 1604: 460470, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31492467

RESUMO

Small organic acids are widely used within the pharmaceutical industry but can be difficult to analyse. Ion chromatography is a suitable technique for the analysis of these acids but method development can be hindered as mass spectrometry is not often used as a detector; this means that peak tracking and peak purity cannot be performed. The authors report method development for the analysis of 2-butynoic acid, where by using electrospray ionisation mass spectrometry, peak purity was investigated and the presence of co-eluting impurities determined. Optimisation of the additives in the make-up flow to the mass spectrometer was shown to have an impact on the response observed. A standard series of organic acids were analysed spiked in to 2-butynoic acid at levels representative of impurities, the presence of the 2-butynoic acid did not impact the linearity or limit of detection observed for the acids; R2 values greater than 0.98 were obtained for all acids with and without the presence of 2-butynoic acid with a limit of detection at 1 ppb for all but one of the acids.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia , Ácidos Graxos Insaturados/análise , Espectrometria de Massas por Ionização por Electrospray , Compostos Orgânicos/análise
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