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1.
Braz. J. Pharm. Sci. (Online) ; 59: e20314, 2023. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1447570

RESUMO

Abstract Betamethasone (BET) is a synthetic glucocorticoid recommended for pregnant women at imminent risk of preterm birth before 34 weeks to reduce neonatal complications. There are different techniques to describe BET plasma quantification. However, none quantified the plasmatic concentration of BET in dichorionic (DC) twin pregnancies using LC-MS. Our objectives were to develop and validate a method for quantifying BET by LC-MS for pharmacokinetic (PK) and placental transfer studies in DC twin pregnancies. Blood samples were collected after intramuscular administration of a single BET dose containing 6 mg disodium phosphate + 6 mg acetate. BET was determined in plasma by liquid-liquid extraction. The method showed linearity in the range of 2-250 ng/mL, as well as precision and accuracy with a coefficient of variation and relative standard errors ≤ 15%. Additionally, the method presented selectivity and did not present matrix or carry-over effect. Stability tests also presented coefficient of variation and relative standard errors ≤ 15%. This is the first study which describe maternal and fetal plasma concentrations of BET in a DC twin pregnancy. The BET PK parameters were AUC0-∞, CL/F, Vd/F, Cmax, Tmax of 292.20 h*ng/mL, 39.08 L/h, 278.72 L, 25.55 ng/mL and 0.58 h, respectively. The placental transfer ratios of umbilical vein/maternal vein and intervillous space/maternal vein were 0.14 and 0.19 and 0.40 and 0.27 for both twins, respectively. However, a clinical study with more subjects is imperative to confirm this higher concentration of BET in the intervillous space


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Plasma/metabolismo , Betametasona/antagonistas & inibidores , Extração Líquido-Líquido/instrumentação
2.
Braz. J. Pharm. Sci. (Online) ; 58: e201066, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1420467

RESUMO

Abstract A simple and selective liquid chromatography tandem with mass spectrometry (LC-MS/ MS) method for quantification of lobetyolin in rat plasma was developed and validated. Chromatographic separation was achieved on a Thermo ODS C18 reversed-phase column using 0.1% aqueous formic acid-methanol (50:50, v/v) in an isocratic elution mode at a flow rate of 0.4 mL.min-1. LC/MS performance was done in a positive ion ESI mode and the MS/MS transitions were monitored at m/z 419.3 [M+Na]+ → m/z 203.1 for lobetyolin and m/z 394.9 [M+Na]+ → m/z 231.9 for IS, respectively. The assay exhibited a linear dynamic range over 1.0-500 ng.mL-1 for lobetyolin in plasma. Both the precision (%RSD) and accuracy (RE%) were within acceptable criteria (<15%). Recoveries ranged from 87.0% to 95.6%, and the matrix effects were from 91.0% to 101.3%. After oral administration, the peak plasma concentration of lobetyolin was obtained as 60.1 ng.mL-1 at 1.0 h. The proposed LC-MS/MS method could be applied to a pharmacokinetic study employing 66 samples from 6 Wistar rats


Assuntos
Animais , Masculino , Feminino , Ratos , Espectrometria de Massas/instrumentação , Cromatografia Líquida/instrumentação , Estudo de Validação
3.
Biomed Pharmacother ; 132: 110900, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33113433

RESUMO

Hancornia speciosa is a medicinal plant with proven antihypertensive activity. The cyclitol l-(+)-bornesitol is the main constituent of its leaves and is a potent inhibitor of the angiotensin-converting enzyme. We herein investigated the pharmacokinetic properties of bornesitol administered orally to Wistar rats, as well as bornesitol permeation in Caco-2 cells. Bornesitol was isolated and purified from an ethanol extract of H. speciosa leaves. An ultra-high performance liquid chromatography coupled with electrospray ionization mass spectrometry (UPLC-ESI-MS/MS) method was developed and validated to quantify bornesitol in rat plasma based on Multiple Reaction Monitoring, using pentaerythritol as an internal standard. Pharmacokinetics was evaluated by the administration of single doses via intravenous in bolus (3 mg/kg) and gavage (3, 15 and 25 mg/kg). Bornesitol permeation was assayed in a transwell Caco-2 cells model, tested alone, or combined with rutin, or as a constituent of H. speciosa extract, using a developed and validated UPLC-ESI-MS/MS method. All assayed validation parameters (selectivity, residual effect, matrix effect, linearity, precision, accuracy and stability of analyte in plasma and solution) for the bioanalytical method met the acceptance criteria established by regulatory guidelines. Bornestiol reached peak plasma concentration within approximately 60 min after oral administration with a half-life ranging from 72.15 min to 123.69 min. The peak concentration and area under the concentration-time curve of bornesitol did not rise proportionally with the increasing doses, suggesting a non-linear pharmacokinetics in rats and the oral bioavailability ranged from 28.5%-59.3%. Bornesitol showed low permeability in Caco-2 cells, but the permeability apparently increased when it was administered either combined with rutin or as a constituent of H. speciosa extract. In conclusion, bornesitol was rapidly absorbed after a single oral administration to rats and followed a non-linear pharmacokinetics. The obtained data will be useful to guide further pre-clinical development of bornesitol-containing herbal preparations of H. speciosa as an antihypertensive agent.


Assuntos
Anti-Hipertensivos/farmacocinética , Apocynaceae , Cromatografia Líquida de Alta Pressão , Ciclitóis/farmacocinética , Extratos Vegetais/farmacocinética , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Administração Oral , Animais , Anti-Hipertensivos/administração & dosagem , Anti-Hipertensivos/sangue , Anti-Hipertensivos/isolamento & purificação , Apocynaceae/química , Disponibilidade Biológica , Células CACO-2 , Ciclitóis/administração & dosagem , Ciclitóis/sangue , Ciclitóis/isolamento & purificação , Humanos , Injeções Intravenosas , Absorção Intestinal , Mucosa Intestinal/metabolismo , Masculino , Modelos Biológicos , Dinâmica não Linear , Permeabilidade , Extratos Vegetais/administração & dosagem , Extratos Vegetais/sangue , Extratos Vegetais/isolamento & purificação , Ratos Wistar
4.
Artigo em Inglês | MEDLINE | ID: mdl-31877429

RESUMO

A simple and fast bioanalytical method for the quantification of kavain in mice plasma was developed using liquid chromatography (LC)-tandem mass spectrometry (MS/MS). A full method validation was performed, according to regulatory guidelines, employing isotopically labeled kavain as the internal standard (racemic-kavain-d3). For the quantification, [M+H]+ was formed using an electrospray ionization (ESI) source in the positive ion mode and multiple reaction monitoring (MRM) was employed using a quadrupole-linear ion trap (4000 QTRAP®) instrument. The monitored MRM transitions were 231.0 â†’ 115.1 and 231.0 â†’ 152.8 for kavain; and 234.2 â†’ 199.2 for the internal standard. A linear response was obtained at the concentration range of 10 to 200 ng/mL with intra- and inter-day variations within the acceptable criteria for all quality control samples. After validation, the method was successfully applied for the quantification of kavain in mice plasma after oral administration of the kavain standard and Kava-kava extract. The plasma concentration over time results were applied for a pharmacokinetics study. The obtained pharmacokinetic parameters indicated a considerably higher bioavailability for kavain when Kava-kava extract was administered due to a pharmacokinetic synergism between the analyte and the other compounds present in the extract.


Assuntos
Cromatografia Líquida/métodos , Pironas/sangue , Pironas/farmacocinética , Espectrometria de Massas em Tandem/métodos , Animais , Feminino , Kava , Limite de Detecção , Modelos Lineares , Camundongos , Extratos Vegetais , Pironas/química , Reprodutibilidade dos Testes
5.
Braz. J. Pharm. Sci. (Online) ; 54(2): e17163, 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951946

RESUMO

ABSTRACT A simple, sensitive and specific liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the quantification of cabozantinib (CZ) in human plasma using cabozantinib-d4 (CZD4) as an internal standard (IS). Chromatographic separation was performed on Xbridge C18, 50 x 4.6 mm, 5 mm column with an isocratic mobile phase composed of 10mM Ammonium formate and Methanol in the ratio of (20:80 v/v), at a flow-rate of 0.7 mL/min. CZ and CZD4 were detected with proton adducts at m/z 502.2 ® 391.1 and 506.3 ® 391.2 in multiple reaction monitoring (MRM) positive mode respectively. Liquid-Liquid extraction method was used to extract the drug and IS. The method was validated over a linear concentration range of 5.0-5000.0 pg/mL with correlation coefficient (r2) ≥ 0.9994. This method demonstrated intra and inter-day precision within 1.95 to 2.37 and 2.93 to 9.3 % and Accuracy within 101.4 to 102.4 and 99.5 to 104.8 %. Cabozantinib was found to be stable throughout freeze-thawing cycles, bench top and postoperative stability studies


Assuntos
Plasma , Farmacocinética , Estudo de Validação , Proteínas Tirosina Quinases , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos
6.
Biomed Chromatogr ; 31(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27557455

RESUMO

We have developed and validated a fast and sensitive ultra high-performance liquid chromatography with positive ion electrospray ionization tandem mass spectrometry method for determining N-butylscopolamine levels in human plasma using propranolol as an internal standard. The acquisition was set up in the multiple reaction monitoring mode with the transitions m/z 360.3 → 138.0 for N-butylscopolamine and m/z 260.2 → 116.1 for IS. This method uses a liquid-liquid extraction process with dichloromethane. The analyte and IS were chromatographed on a C18 , 50 × 2.1 mm, 1.7 µm column through isocratic elution with acetonitrile-5 mm ammonium acetate (adjusted to pH 3.0 with formic acid). The method was linear in the 1-1000 pg/mL range for N-butylscopolamine and was selective, precise, accurate and robust. The validated method was successfully applied to perform a bioequivalence study of the reference (Buscopan® , from Boehringer Ingelheim) and the test sample coated-tablet formulations (from Foundation for Popular Remedy), both containing 10 mg of N-butylscopolamine bromide administered as a single dose. Using 58 healthy volunteers and accounting for the high intra-individual variability confirmed by statistical calculations (38%), the two formulations were considered bioequivalent because the rate and extent of absorption (within 80-125% interval), satisfying international requirements.


Assuntos
Brometo de Butilescopolamônio/sangue , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Humanos
7.
Clin Exp Pharmacol Physiol ; 42(3): 305-13, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25491375

RESUMO

1. A rapid method using liquid chromatography tandem mass spectrometry for the quantification of olanzapine (OLZ) in human plasma was developed and validated. Venlafaxine was used as the internal standard (IS), and the samples were extracted from 400-µL human plasma with methyl tert-butyl ether for liquid-liquid extraction. 2. Chromatography was performed using an ACE C18, 125 × 4.6-mm i.d., 5-µm column. The mobile phase consisted of water with 0.1% formic acid for solvent A and acetonitrile with 0.1% formic acid for solvent B (50 : 50 v/v) in isocratic mode. The flow rate was 1.2 mL/min. The retention times for OLZ and the IS were 0.78 and 1.04 min, respectively. Tandem mass spectrometry operating in positive electrospray ionization mode with multiple reaction monitoring was used to detect OLZ and the IS (m/z: 313.1 > 256.1 and 278.1 > 260.2, respectively). 3. No significant matrix effects were observed on OLZ and the IS retention times, and the mean recovery of OLZ was 90.08%. The assay was linear in the concentration range of 1-20 ng/mL (R(2) = 0.9976). The intra- and inter-day precision were < 11.60% and the accuracy was < 1.66%. 4. This validated method was successfully applied to a pharmacokinetic study in which 10-mg OLZ tablets were administered to healthy volunteers and their plasma OLZ levels were monitored over time. The tests showed that the OLZ test and reference drug (Zyprexa(®)) were bioequivalent, as 90% of the confidence intervals were within the 80-125% interval proposed by regulatory agencies.


Assuntos
Benzodiazepinas/sangue , Benzodiazepinas/farmacocinética , Análise Química do Sangue/métodos , Espectrometria de Massas em Tandem , Adolescente , Adulto , Cromatografia Líquida , Estabilidade de Medicamentos , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Olanzapina , Distribuição Tecidual , Adulto Jovem
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