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1.
Artigo em Inglês | MEDLINE | ID: mdl-33540148

RESUMO

A rapid, reliable and eco-friendly method for the determination of three sex hormones in five kinds of milk was developed and validated by combining vortex-assisted liquid-liquid microextraction (VALLME) and magnetic solid-phase extraction (MSPE). Deep eutectic solvents (DESs) such as choline chloride/urea were considered as the extraction solvent in VALLME and multi-walled carbon nanotubes (MMWCNTs) were used as the adsorbent which could adsorb DESs on the surface. The optimum experimental conditions were as follows: amount of MMWCNTs for 10 mg, volume of acetone for 4 mL, no sodium chloride and extraction pH at 7. After the optimization of several main variables, satisfactory sensitivity levels were achieved as low as 1.0-1.3 ng mL-1 and 2.5-4.5 ng mL-1 for the limit of method detections and the limit of method quantitation, respectively. The recoveries of the three hormones in different milk samples were in the range of 80.1%-116.4%. Consequently, this method is suitable for monitoring the trace amount of sex hormones in milk matrices.


Assuntos
Hormônios Esteroides Gonadais/análise , Microextração em Fase Líquida/métodos , Nanopartículas de Magnetita/química , Leite/química , Extração em Fase Sólida/métodos , Animais , Bovinos , Resíduos de Drogas/análise , Resíduos de Drogas/química , Resíduos de Drogas/isolamento & purificação , Hormônios Esteroides Gonadais/química , Hormônios Esteroides Gonadais/isolamento & purificação , Limite de Detecção , Modelos Lineares , Nanotubos de Carbono/química , Reprodutibilidade dos Testes , Solventes
2.
Artigo em Inglês | MEDLINE | ID: mdl-30878759

RESUMO

ATP-Binding Cassette, subfamily B, member 6 (ABCB6) is a transporter that is upregulated by elevated intracellular porphyrin concentrations. In the Harderian gland (HG), the synthesis of porphyrins appears to be under the influence of gonadal steroids and to exhibit a dimorphic pattern. To explore whether ABCB6 is also influenced by sex steroids, we isolated its specific cDNA sequence and investigated its mRNA levels in the HGs of hamsters. ABCB6's cDNA sequence presents an open reading frame (ORF) of 2529 bp that encodes a predicted 842-amino acid (aa) protein with a molecular weight of 93 kDa. Multiple sequence alignments showed that ABCB6's aa sequence is highly conserved and shares the highest homology (93%) with mouse ABCB6. RT-qPCR analysis indicated that ABCB6 is expressed in all the tissues examined, exhibiting high expression levels in the liver, adrenal glands, and testis. The mRNA concentrations of ABCB6 in HGs were very similar between males and in females; similarly, gonadectomy and treatment with sex steroids appear to scarcely affect ABCB6 mRNA levels. The intraglandular content of ABCB6 mRNA showed discrete, though non-significant, variations through the estrous cycle. The results provide evidence that gonadal steroids have a minimal physiological role on the regulation of ABCB6 expression and might indicate that this transporter has a small effect on porphyrin trafficking in the HGs of hamsters.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Glândula de Harder/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Cricetinae , Feminino , Hormônios Esteroides Gonadais/isolamento & purificação , Masculino , Mesocricetus , Alinhamento de Sequência
3.
Biomed Microdevices ; 21(1): 16, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30747285

RESUMO

We present an open microfluidic platform that enables stable flow of an organic solvent over an aqueous solution. The device features apertures connecting a lower aqueous channel to an upper solvent compartment that is open to air, enabling easy removal of the solvent for analysis. We have previously shown that related open biphasic systems enable steroid hormone extraction from human cells in microscale culture and secondary metabolite extraction from microbial culture; here we build on our prior work by determining conditions under which the system can be used with extraction solvents of ranging polarities, a critical feature for applying this extraction platform to diverse classes of metabolites. We developed an analytical model that predicts the limits of stable aqueous-organic interfaces based on analysis of Laplace pressure. With this analytical model and experimental testing, we developed generalized design rules for creating stable open microfluidic biphasic systems with solvents of varying densities, aqueous-organic interfacial tensions, and polarities. The stable biphasic interfaces afforded by this device will enable on-chip extraction of diverse metabolite structures and novel applications in microscale biphasic chemical reactions.


Assuntos
Hormônios Esteroides Gonadais/isolamento & purificação , Microfluídica , Linhagem Celular Tumoral , Hormônios Esteroides Gonadais/metabolismo , Humanos , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Microfluídica/instrumentação , Microfluídica/métodos , Propriedades de Superfície
4.
J Chromatogr A ; 1580: 12-21, 2018 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-30391035

RESUMO

A hexafluroisopropanol (HFIP)-alkyl carboxylic acid high-density supramolecular solvent (SUPRAS) was proposed and combined with dispersive liquid-liquid microextraction (DLLME) for extraction and preconcentration of steroid sex hormones in human urine prior to analysis by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Octanoic acid was used as extraction agent and HFIP, with the properties of high density, strong hydrogen bond donor and high hydrophobicity, was used as dispersing agent of DLLME as well as coacervation-inducing agent and density-regulating agent of octanoic acid. HFIP-octanoic acid SUPRAS was spontaneously formed in the process of DLLME and located in the bottom of a urine solution due to its density higher than water. Thus, the SUPRAS phase at trace volume was easy to be collected after centrifugation using normal centrifuge tubes. Five hormones (four estrogens and progesterone) were chosen as analytes. Urine hydrolysis time, extraction conditions and derivatization conditions for estrogens were optimized. Under the optimal conditions, only 0.07 mL of organic solvent (HFIP) was consumed. An external standard calibration method was used for quantification, and a linear relationship was obtained with correlation coefficients higher than 0.9957 and p values for linear trend less than 0.0001. Limits of detection of the method based on a signal-to-noise ratio of 3 were 0.01-0.10 µg L-1. The recoveries ranged from 82.7% to 120.2%, and intra-day and inter-day relative standard deviations of the method were less than 15%. The matrix effects of 84.0%-105.7% showed no urine matrix interferences with MS detection, which was mainly due to the restricted access property of HFIP-octanoic acid SUPRAS with reverse micelle aggregates. The absence of matrix effects contributed to the reliable quantitation by external calibration, avoiding the use of expensive isotopically labeled internal standards. The novel SUPRAS-based DLLME method, coupled with HPLC-MS/MS, was applied for determination of target hormones in real urine.


Assuntos
Ácidos Carboxílicos/química , Hormônios Esteroides Gonadais/isolamento & purificação , Microextração em Fase Líquida , Propanóis/química , Urinálise/métodos , Urina/química , Cromatografia Líquida de Alta Pressão , Hormônios Esteroides Gonadais/análise , Humanos , Interações Hidrofóbicas e Hidrofílicas , Limite de Detecção , Solventes/química , Espectrometria de Massas em Tandem
5.
Electrophoresis ; 38(12): 1632-1643, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28304112

RESUMO

The goal of this study was to assess various analytical approaches for the simultaneous and efficient extraction of steroid hormones (cortisone, cortisol, prednisolone, corticosterone, testosterone, 17α-methyltestosterone, epitestosterone, progesterone) from urine samples prior to separation based on field-amplified sample stacking MEKC (FASS-MEKC). FASS-MEKC successfully allowed the compounds to be separated within 12 min using a BGE composed of 5 mM sodium tetraborate, 150 mM boric acid, 50 mM SDS, and 15% methanol. Therefore, many procedures such as solid-phase microextraction, SPE, and dispersive liquid-liquid microextraction (DLLME) were tested and compared using a multivariate tool, namely, cluster analysis. Finally, DLLME-FASS-MEKC was validated and proved a good linearity of calibration curves (R2 above 0.9948) in a concentration range from 50 to 1000 ng/mL for all analytes. The LOD was established at 15 ng/mL, whereas the LOQ was 50 ng/mL. The intra- and interday precision, expressed as RSD%, did not exceed 9.97%. The DLLME-FASS-MEKC method was successfully applied to the analysis of urine samples from healthy volunteers and sportsmen. This methodology could prove to be useful in clinical studies and/or doping control depending on the steroid concentrations required in biomedical applications.


Assuntos
Hormônios Esteroides Gonadais/urina , Cromatografia Capilar Eletrocinética Micelar , Doping nos Esportes , Eletroforese Capilar , Hormônios Esteroides Gonadais/isolamento & purificação , Limite de Detecção , Microextração em Fase Líquida , Sensibilidade e Especificidade , Congêneres da Testosterona/urina
6.
J Sep Sci ; 39(18): 3571-7, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27470965

RESUMO

An iron-embedded porous carbon material (MIL-53-C) was fabricated by the direct carbonization of MIL-53. The MIL-53-C possesses a high surface area and good magnetic behavior. The structure, morphology, magnetic property, and porosity of the MIL-53-C were studied by scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, and N2 adsorption. With the use of MIL-53-C as the magnetic solid-phase extraction adsorbent, a simple and efficient method was developed for the magnetic solid-phase extraction of three hormones from water and human urine samples before high-performance liquid chromatography with UV detection. The developed method exhibits a good linear response in the range of 0.02-100 ng/mL for water and 0.5-100 ng/mL for human urine samples, respectively. The limit of detection (S/N = 3) for the analytes was 0.005-0.01 ng/mL for water sample and 0.1-0.3 ng/mL for human urine sample. The limit of quantification (S/N = 10) of the analytes were in the range of 0.015-0.030 and 0.3-0.9 ng/mL, respectively.


Assuntos
Hormônios Esteroides Gonadais/isolamento & purificação , Magnetismo/métodos , Estruturas Metalorgânicas/química , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Carbono/química , Cromatografia Líquida de Alta Pressão , Hormônios Esteroides Gonadais/química , Hormônios Esteroides Gonadais/urina , Humanos , Limite de Detecção , Magnetismo/instrumentação , Porosidade , Extração em Fase Sólida/instrumentação , Poluentes Químicos da Água/química
7.
Pesqui. vet. bras ; 35(3): 304-310, 03/2015. tab, graf
Artigo em Português | LILACS | ID: lil-751976

RESUMO

A comunicação do estado reprodutivo nos primatas da família Callithrichidae, depende principalmente dos comportamentos sócio-sexuais como um sistema de sinalização primário, uma vez que nestas espécies a ovulação não é percebida pelos machos. Neste trabalho, os padrões de comportamentos sócio-sexuais foram analisados em conjunto com as concentrações de metabólitos fecais dos esteróides sexuais progesterona (MFP), estradiol (MFE) e testosterona (MFT) em casais cativos de Sagüi-de-tufos-pretos (Callithrix penicillata), nas diferentes fases do ciclo ovariano. O grupo estudado era composto por quarto casais adultos, mantidos no Centro de Reabilitação de Animais Selvagens da prefeitura de São Paulo. Os padrões comportamentais foram registrados pelo método de amostragem focal por intervalo de tempo a cada 30 segundos, cinco vezes por semana, totalizando 14.400 registros por animal. A mensuração das concentrações de metabólitos fecais dos esteroides sexuais foram realizados pelo método de enzima imunoensaio (EIE). Os resultados obtidos dessas concentrações possibilitaram a determinação endócrina das fases do ciclo ovariano (folicular e luteal) e de suas respectivas durações, assim como a determinação da fase periovulatória. Foram caracterizados 31 ciclos ovarianos completos, com duração de 24,3±4,1 dias (média ±DP), sendo que a fase folicular compreendeu 13,04±4,8dias e a fase lútea 11,2±4,2 dias. Os comportamentos sócio-sexuais (marcação por cheiro, cheirar genitália, catação e apresentação sexual) e a variável "proximidade" mostraram-se significativamente mais prevalentes na fase periovulatória do que nas demais fases do ciclo. Não houve alteração das concentrações de MFT dos machos ao longo de todo o período estudado. A análise conjunta das concentrações de metabólitos fecais de esteróides sexuais e dos comportamentos sócio-sexuais possibilitou um melhor entendimento das relações endócrino-comportamentais e reprodutivas de C. penicillata.


The communication of the female reproductive status in Callithrichidae relies mainly on the socio-sexual behavior, as generally the ovulation is concealed in this primate family by a primary signaling system. In this study the socio-sexual behavior patterns was analyzed in association with the concentration of fecal metabolites of sex steroid hormones progesterone (MFP), estradiol (MFE) and testosterone (MFT) in captive couples of Black-Tufted-Marmoset (Callithrix penicillata), during the different phases of the ovarian cycle. The studied group was composed of four adult couples kept in the São Paulo City Wild Animals Rehabilitation Center. The behavioral patterns were record by focal samplings, with 30 seconds intervals for each observation, five days a week, totalizing 14.400 registers per animal. The measurement of fecal metabolites of progesterone (MFP), estradiol (MFE) and testosterone (MFT) proceeded by enzyme immune assay (EIA). The results allowed to determine the duration of the ovarian cycle and to characterize three different phases (follicular, periovulatory and luteal). It was possible to determine 31 complete cycles that lasted 24.3±4.1 days (Mean ± SD). The follicular and luteal phases lasted 13.04±4.8 and the luteal phase 11.2±4.2 days. The behavioral patterns (scent marking, sniff genitals, grooming and sexual presentation) were more prevalent in the periovulatory phase as the behavioral variable "proximity" as well. There were no variations in the concentration of MFT in the males during the period studied. The associated analyses of the fecal metabolite of sex steroids and the socio-sexual behaviors led to a better understanding of the factors involved in the reproduction of C. penicillata.


Assuntos
Animais , Callithrix/fisiologia , Comportamento Sexual Animal/fisiologia , Hormônios Esteroides Gonadais/isolamento & purificação , Comportamento Social , Estradiol , Progesterona , Testosterona
8.
J Sep Sci ; 37(9-10): 1094-102, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24596023

RESUMO

In this study, we investigate the separation of a variety of mixtures of drugs, metabolites, and related analogs including representatives of the carbamazepine, methylated xanthine, steroid hormone, nicotine, and morphine families using several automated chromatographic method development screening systems including ultra high performance liquid chromatography, core-shell HPLC, achiral supercritical fluid chromatography (SFC), and chiral SFC. Of the 138 column and mobile phase combinations examined for each mixture, a few chromatographic conditions afford the best overall performance, with a single achiral SFC method (4.6 × 250 mm, 3.0 µm GreenSep Ethyl Pyridine, 25 mM isobutylamine in methanol/CO2) affording good separation for all samples. Four of these mixtures were also resolved by achiral SFC on the Luna HILIC and chiral SFC Chiralpak IB columns using methanol or ethanol with 25 mM isobutylamine as polar modifiers. Modifications of standard chromatography screening conditions afforded fast separation methods (from 1 to 5 min) for baseline resolution of all components of each of these challenging sets of closely related compounds.


Assuntos
Carbamazepina/isolamento & purificação , Hormônios Esteroides Gonadais/isolamento & purificação , Derivados da Morfina/isolamento & purificação , Nicotina/isolamento & purificação , Xantina/isolamento & purificação , Carbamazepina/química , Carbamazepina/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia com Fluido Supercrítico , Hormônios Esteroides Gonadais/química , Hormônios Esteroides Gonadais/metabolismo , Estrutura Molecular , Derivados da Morfina/química , Derivados da Morfina/metabolismo , Nicotina/química , Nicotina/metabolismo , Xantina/química , Xantina/metabolismo
9.
J Sep Sci ; 37(4): 345-51, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24339351

RESUMO

The chromatographic behavior of steroid hormones on four cholesterol-bonded stationary phases with different structures in binary methanol/water mobile phases was studied. Of the stationary phases tested, the commercially available stationary phases Cogent UDC cholesterol™ and COSMOSIL cholester™ provided better separations of steroid hormones in comparison to homemade aminocholesterol and diaminocholesterol stationary phases. The results show that the temperature has a significant influence on the retention and selectivity for steroid hormones separation. The temperature increase may cause changes in the elution order. From the dependences of the retention (ln k) on temperature (1/T), the standard partial molar enthalpy and standard partial molar entropy were calculated and their enthalpic and entropic contributions to the retention were compared. The enthalpic effects principally control the retention mechanism.


Assuntos
Colesterol/química , Hormônios Esteroides Gonadais/isolamento & purificação , Metanol/química , Termodinâmica , Água/química
10.
Talanta ; 115: 349-60, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054602

RESUMO

An analytical method based on on-line SPE-LC-APCI-MS/MS has been developed for the detection and quantification of eight selected estrogenic and progestagenic steroid hormones; estrone (E1), 17ß-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2), levonorgestrel (LEVO), medroxyprogesterone (MEDRO), norethindrone (NORE) and progesterone (PROG) in wastewater matrices. The injection volume could range from 1 to 10-mL according to the expected concentration of steroid hormones in matrix. The method characteristics are: analysis time per sample (<15 min), acceptable recovery values (71-95%), good precision (RSD ≤ 10%) and limits of detection at the low-nanogram per liter levels in affluent and effluent wastewaters (8-60 ng L(-1)). In particular, a detailed discussion of optimization parameters impacting overall performance of the method has been presented (sample collection, filtration and storage). All optimization and validation experiments for the on-line SPE method and chromatographic separation were performed in environmentally-relevant wastewater matrices. This method represents a compromise between analysis time, higher sample throughput capabilities, sample volume and simplicity for the analysis of both progestagenic and estrogenic steroid hormones in a single run, with LODs and LOQs sufficiently low to detect and quantify them in environmental wastewater matrices. Thus, the applicability of the method was tested on affluent and effluent wastewaters from two wastewater treatment facilities using different processes (biological and physico-chemical) to evaluate their removal efficiency for the detected steroid hormones.


Assuntos
Hormônios Esteroides Gonadais/isolamento & purificação , Extração em Fase Sólida/métodos , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Cromatografia Líquida/métodos , Humanos , Limite de Detecção , Reprodutibilidade dos Testes , Solventes , Manejo de Espécimes , Espectrometria de Massas em Tandem/métodos , Fatores de Tempo
11.
Talanta ; 115: 367-73, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-24054604

RESUMO

In this paper, a new working approach is described for the analysis of steroids as environmental water pollutants. As novelty to the field, steroids were identified and quantified both in the dissolved and in the suspended phases, as their trimethylsilyl-(oxime)-ether derivatives, applying a recently developed tandem gas chromatographic mass spectrometric (GC-MS/MS) method, applying multiple reaction monitoring (MRM) acquisition, suitable for their quantitation in the low ng/L level, in wastewater and in Danube River samples. In addition to the analysis of filtrates obtained by the common solid phase extraction (SPE) enrichment, even the insoluble, isolated by filtration prior to the SPE, and usually discarded part of steroids were identified and quantified, simultaneously, for the first time. For this purpose a new, time, labor, cost efficient and quantitative, ultrasound assisted extraction process was developed. Reproducibility, reliability and practical utility of the ultrasound assisted extraction process were proved by the proportionality of the extracted suspended steroids obtained from different sample volumes: prepared from 0.5L and 1.0 L influent wastewater, as well as from 3 L, 5 L and 10 L Danube River water samples. Steroids' concentrations, identified and quantified in suspended conditions, showed proportionality, characterized with the relative standard deviation percentages (RSD%) of analyses: varying in case of Danube River water in the range of 0.92-6.0%, with an average of 4.10% RSD, while in the case of influent wastewater in the range of 1.59-5.8%, with an average of 4.03% RSD. Partition of steroids, between the dissolved and suspended phases of influent and effluent wastewaters and river water samples, meaning, the total amounts of steroids that the ecosystem is liable to, were defined in river water samples for the first time. Distribution of found steroids revealed that their considerable and/or overwhelming part (relating to their total amounts), are present in suspended phases: in average, 71% from wastewater and 64% from Danube River samples.


Assuntos
Hormônios Esteroides Gonadais/isolamento & purificação , Rios/química , Extração em Fase Sólida/métodos , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Cromatografia Gasosa/métodos , Humanos , Hungria , Limite de Detecção , Reprodutibilidade dos Testes , Solubilidade , Solventes , Sonicação , Suspensões , Espectrometria de Massas em Tandem/métodos , Fatores de Tempo
12.
Toxicol Appl Pharmacol ; 272(1): 127-36, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23714657

RESUMO

Bisphenols are a group of chemicals structurally similar to bisphenol-A (BPA) in current use as the primary raw material in the production of polycarbonate and epoxy resins. Some bisphenols are intended to replace BPA in several industrial applications. This is the case of bisphenol-S (BPS), which has an excellent stability at high temperature and resistance to sunlight. Studies on the endocrine properties of BPS have focused on its interaction with human estrogen receptor alpha (hERα), but information on its interaction with other nuclear receptors is scarce. The aim of this study was to investigate interactions of BPS, BPF, BPA and its halogenated derivatives, tetrachlorobisphenol A (TCBPA), and tetrabromobisphenol A (TBBPA), with human estrogen receptors (hERα and hERß), androgen receptor (hAR), and pregnane X receptor (hPXR), using a panel of in vitro bioassays based on competitive binding to nuclear receptors (NRs), reporter gene expression, and cell proliferation assessment. BPS, BPF, and BPA efficiently activated both ERs, while TCBPA behaved as weak hERα agonist. Unlike BPF and BPA, BPS was more active in the hERß versus hERα assay. BPF and BPA were full hAR antagonists (BPA>BPF), whereas BPA and BPS were weak hAR agonists. Only BPA, TCBPA, and TBBPA, were hPXR agonists (TCBPA>TBBPA>BPA). These findings provide evidence that BPA congeners and derivatives disrupt multiple NRs and may therefore interfere with the endocrine system. Hence, further research is needed to evaluate the potential endocrine-disrupting activity of putative BPA substitutes.


Assuntos
Compostos Benzidrílicos/farmacologia , Fenóis/farmacologia , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Sulfonas/farmacologia , Ligação Competitiva/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Disruptores Endócrinos/toxicidade , Receptor alfa de Estrogênio/efeitos dos fármacos , Receptor beta de Estrogênio/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônios Esteroides Gonadais/isolamento & purificação , Humanos , Luciferases/metabolismo , Plasmídeos/genética , Receptor de Pregnano X , Receptores Androgênicos/efeitos dos fármacos , Receptores de Esteroides/efeitos dos fármacos
13.
J Chromatogr A ; 1283: 39-45, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23465128

RESUMO

A sensitive analytical method is presented for the simultaneous determination of four synthetic estrogens and six steroid hormones in sludge-amended soil. The method employs matrix solid-phase dispersion (MSPD) followed by isotope dilution gas chromatography-tandem mass spectrometry injecting a large volume sample (10µL) after trimethylsilyl derivatization, using the solvent vent mode. It affords good resolution, high sensitivity and reproducibility and freedom from interferences even from complex matrices as soil amended with sewage sludge. The limits of detection (LODs) ranged from 10 to 300pgg(-1) with testosterone and progesterone having the highest limits. Soil amended with sewage sludge was spiked at 2, 10, 25 and 50ngg(-1) and the recoveries after MSPD with acetonitrile:methanol (90:10, v/v), ranged from 80 to 110% with relative standard deviations ≤9%. The method was applied to the analysis of six soil samples collected from agricultural plots and forested fields that had been amended with sewage sludge using isotopically labeled surrogates. Three of the synthetic estrogens studied were found at least in one of the six samples analyzed and trans-androsterone and estrone were the only natural hormones detected, although at very low levels (≤0.4ngg(-1)).


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Hormônios Esteroides Gonadais/análise , Esgotos/química , Poluentes do Solo/análise , Extração em Fase Sólida/métodos , Hormônios Esteroides Gonadais/química , Hormônios Esteroides Gonadais/isolamento & purificação , Limite de Detecção , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Preparações Farmacêuticas/isolamento & purificação , Reprodutibilidade dos Testes , Poluentes do Solo/química , Poluentes do Solo/isolamento & purificação , Espectrometria de Massas em Tandem
14.
J Chromatogr Sci ; 50(4): 349-57, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22407346

RESUMO

Studying the plasma steroid profile offers information about the possible existence of endocrinological alterations. This study describes the development and validation of gas chromatographic-mass spectrometric and gas tandem mass spectrometric methods for the simultaneous identification of 17 steroid hormones in human plasma using five different solvents. The n-hexane/ethyl acetate solvent mixture, in a proportion of 70/30 (v/v) provided the best results. The extracts were derivatized with N-methyl-N-trimethylsilyl-trifluoroacetamide. The obtained limits of detection were below 1 ng/mL in the majority of the studied steroids and the limits of quantification were below 5 ng/mL; the method obtained good linearity, reproducibility, repeatability, accuracy and recoveries above 95% in most cases.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Hormônios Esteroides Gonadais/sangue , Espectrometria de Massas em Tandem/métodos , Acetatos , Albuminas , Hormônios Esteroides Gonadais/isolamento & purificação , Hexanos , Humanos , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Anal Chim Acta ; 678(1): 108-16, 2010 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-20869511

RESUMO

A method was developed for simultaneous determination of residues of 17 sex hormones in egg products. Target compounds were extracted from samples with methanol in an ultrasonic bath, effectively separated from lipids in the extracts by ZnCl(2) depositing filtration and purified using a C(18) solid-phase extraction (SPE) and followed by NH(2) SPE cartridge. The analytes were quantified by liquid chromatography using a BEH C(18) column coupled to an electrospray ionization tandem mass spectrometer (LC-ESI-MS/MS) operating in negative mode for estrogens and in positive multiple reaction monitoring mode for androgens. The parameters of the mass spectrometer and the composition of mobile phase and additives were also optimized to enhance detection sensitivity. Average recoveries of the target compounds varied from 70.0% to 121.0% with relative standard deviations ranging from 2.3% to 11.2% at two fortification levels. The limits of detection (LOD) of the method were from 0.002 µg kg(-1) to 0.23 µg kg(-1) and the limits of quantification (LOQ) were in the range of 0.007-0.76 µg kg(-1).


Assuntos
Cloretos/química , Cromatografia Líquida de Alta Pressão/métodos , Ovos/análise , Hormônios Esteroides Gonadais/análise , Extração em Fase Sólida/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Compostos de Zinco/química , Análise de Alimentos , Hormônios Esteroides Gonadais/isolamento & purificação
16.
Electrophoresis ; 30(4): 599-606, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19170057

RESUMO

Butyl acrylate (BA)- and lauryl acrylate (LA)-based monolithic stationary phases for CEC were synthesized, using a redox system as initiator of polymerization. BA monoliths were initiated with ammonium peroxodisulfate, whereas LA columns were obtained with lauroyl peroxide as initiator. In both cases, TEMED was used to activate the process. The influence of porogenic solvent composition on both morphological and electrochromatographic properties of the resulting monoliths was investigated. Excellent efficiencies (minimum plate heights of 4.2-6.3 microm for BA columns and 2.6-5.3 microm for LA stationary phases, for a PAHs mixture) were achieved. The capability of separation of both types of monolithic beds was compared by the analysis of complex mixtures of polycyclic aromatic hydrocarbons and anabolic steroids.


Assuntos
Acrilatos/química , Eletrocromatografia Capilar/métodos , Sulfato de Amônio/química , Etilenodiaminas/química , Hormônios Esteroides Gonadais/química , Hormônios Esteroides Gonadais/isolamento & purificação , Peróxidos Lipídicos/química , Microscopia Eletrônica de Varredura , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/isolamento & purificação , Reprodutibilidade dos Testes
17.
Biomed Chromatogr ; 22(1): 34-43, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17624919

RESUMO

A sensitive liquid chromatography-electrospray ionization-tandem mass spectrometric (LC-ESI-MS/MS) method for the simultaneous determination of five 3-oxo-4-ene-neuroactive steroids, i.e. androstenedione, testosterone (T), progesterone (PROG), 20alpha-dihydroprogesterone and 20beta-dihydroprogesterone, in rat brain has been developed and validated. The brain steroids were extracted with methanol-acetic acid, purified using solid-phase extraction cartridges and subjected to LC-ESI-MS/MS. The method does not require derivatization. Deuterium-labeled T and PROG were used as the internal standards, and quantification was based on the selected reaction monitoring mode. This method allowed the reproducible and accurate quantification of the brain neuroactive steroids using 100 mg of tissue; the intra- and inter-assay relative standard deviations were below 4.7 and 4.3%, respectively, and the accuracy values were 97.6-103.2% for all the steroids. The limits of quantitation were 0.1 ng/g tissue for all the steroids. The application of this developed method for the analysis of changes in the brain neuroactive steroid levels by immobilization stress is also presented.


Assuntos
Química Encefálica , Hormônios Esteroides Gonadais/isolamento & purificação , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , 20-alfa-Di-Hidroprogesterona/isolamento & purificação , Ácido Acético/química , Androstano-3,17-diol/isolamento & purificação , Animais , Deutério/química , Hormônios Esteroides Gonadais/classificação , Masculino , Metanol/química , Progesterona/química , Progesterona/isolamento & purificação , Ratos , Ratos Wistar , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Extração em Fase Sólida , Testosterona/isolamento & purificação
18.
Zhongguo Zhong Yao Za Zhi ; 32(19): 2000-3, 2007 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-18161290

RESUMO

OBJECTIVE: To study the method of extraction of sex hormone from antler velvet with supercritical CO2. METHOD: Supercritical fluid extraction (SFE) was used to extract sex hormone from antler velvet and radioimmunoassay (RIA) was used to analyze the extracts. The chemical compositions in extracts were identified by GC-MS, TLC and HPLC, respectively. RESULT: The experimental results indicated that the extraction yield was 1.56% when 85% ethanol was used as co-solvent at temperature of 65 degrees C and extraction pressure of 30 MPa. Estradiol and progesterone in the extracts were 3.07, 776.18 ng x g(-1) respectively. CONCLUSION: It is feasible to extract hormone from antler velvet with supercritical CO2.


Assuntos
Chifres de Veado/química , Cromatografia com Fluido Supercrítico/métodos , Hormônios Esteroides Gonadais/isolamento & purificação , Materia Medica/química , Animais , Dióxido de Carbono , Estradiol/isolamento & purificação , Etanol , Progesterona/isolamento & purificação , Radioimunoensaio
19.
J Biosci Bioeng ; 103(1): 27-31, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17298897

RESUMO

An efficient treatment process for screened cow manure waste, particularly for the degradation of natural steroid hormones, was developed. The first step in this process was a draw-and-fill process for thermophilic anaerobic digestion. After fourfold dilution with tap water, continuous feeding was performed for the aerobic treatment of the effluent from the anaerobic treatment. Batchwise ozone oxidation was then carried out for the degradation of the natural steroid hormones that remained in the effluent from the aerobic treatment. A yeast two-hybrid assay was performed to evaluate hormonal degradation. Significant reductions in the concentrations of total VFA, BOD(5), COD(Cr), TOC, TS, VSS, and natural steroid hormones were demonstrated in the effluent from the biological treatments. The removal ratios of such concentrations were 99.7%, 90%, 79%, 84%, 51%, 58%, and 99%, respectively. Although the concentrations of the remaining TOC and COD(Cr) remained constant, natural steroid hormones were completely removed by ozone oxidation.


Assuntos
Archaea/metabolismo , Fezes/química , Fezes/microbiologia , Hormônios Esteroides Gonadais/química , Hormônios Esteroides Gonadais/metabolismo , Resíduos Industriais/prevenção & controle , Esterco/microbiologia , Agricultura/métodos , Animais , Biodegradação Ambiental , Bovinos , Hormônios Esteroides Gonadais/isolamento & purificação , Oxirredução , Ozônio/química
20.
J Steroid Biochem Mol Biol ; 99(4-5): 203-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16644209

RESUMO

Previous in vitro experiments showed that both, Taenia crassiceps and Taenia solium cysticerci have the ability to metabolize exogenous androstenedione to testosterone. Here we evaluate on the capacity of both cysticerci to synthesize several sex steroid hormones, using different hormonal precursors. Experiments using thin layer chromatography (TLC) showed that both cysticerci were able to produce (3)H-hydroxyprogesterone, (3)H-androstenedione and (3)H-testosterone when (3)H-progesterone was used as the precursor. They also synthesized (3)H-androstenediol and (3)H-testosterone when (3)H-dehydroepiandrosterone was the precursor. In addition, both cysticerci interconverted (3)H-estradiol and (3)H-estrone. These results, strongly suggest the presence and activity of the Delta4 and Delta5 steroid pathway enzymes, 3beta-hydroxysteroid dehydrogenase/Delta(5-4) isomerase-like enzyme (3beta-HSD), that converts androstenediol into testosterone; and the 17beta-hydroxysteroid dehydrogenase that interconverts estradiol and estrone, in both types of cysticerci.


Assuntos
Hormônios Esteroides Gonadais/metabolismo , Taenia solium/metabolismo , Taenia/metabolismo , Teníase/veterinária , Androgênios/metabolismo , Animais , Estrogênios/metabolismo , Hormônios Esteroides Gonadais/isolamento & purificação , Suínos , Doenças dos Suínos/parasitologia , Taenia solium/isolamento & purificação , Teníase/metabolismo
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