RESUMO
INTRODUCTION: Vaginal route is often used in topical antifungal formulations. Vaginal permeability assays are generally performed as in vitro tests. METHOD: An in vivo vaginal permeability assay was developed using female rabbits. Fenticonazole permeability was evaluated by assessing fenticonazole bioavailability in plasma by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS). Toxicity was monitored histopathologically after 8 consecutive days of antifungal treatment (20â¯mg/animal). RESULTS: The method of quantification was linear with a lower limit of quantification (LLOQ) of (0.1â¯ng/mL). The area-under-the-curves (AUC) of fenticonazole on day 1 and 8 of treatment were 280.3⯱â¯86.1â¯ng/mLâ¯∗â¯h and 805.7⯱â¯252.4â¯ng/mLâ¯∗â¯h, respectively. The calculated systemic bioavailability was 12.73%⯱â¯0.14%. No signs of toxicity were observed both macroscopically and histologically after 8â¯days fenticonazole treatment. DISCUSSION: The plasma levels of fenticonazole observed in rabbits are similar to that observed in human. Rabbit vagina may be a suitable model to evaluate vaginal antifungal formulations.
Assuntos
Antifúngicos/administração & dosagem , Antifúngicos/efeitos adversos , Imidazóis/administração & dosagem , Imidazóis/efeitos adversos , Vagina/metabolismo , Administração Intravaginal , Animais , Antifúngicos/sangue , Área Sob a Curva , Disponibilidade Biológica , Cromatografia Líquida/métodos , Feminino , Imidazóis/sangue , Permeabilidade , Coelhos , Espectrometria de Massas em Tandem/métodosRESUMO
A simple, selective and sensitive method based on high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS) has been developed for the determination of dapaconazole in human plasma using tioconazole as internal standard. The drugs were extracted from plasma by liquid-liquid extraction with ether/hexane (80/20, v/v). The chromatography separation was performed on a Genesis(®) C18 reversed phase analytical column 4µm (100×2.1mm i.d.) with a mobile phase of methanol/acetonitrile/water (80/10/10, v/v/v)+ammonium acetate (0.5mM). Dapaconazole was quantified using a mass spectrometer with an electrospray source in the ESI positive mode (ES+) configured for multiple reaction monitoring (MRM) to monitor the transitions 415.1>159.2 and 387.0>131.0 for dapaconazole and tioconazole, respectively. The method had a chromatography run time of 3.8min and a linear calibration curve over the range 0.2-100ng/mL (r=0.9998). The lower limit of quantification (LLOQ) was 0.2ng/mL. The precision and accuracy values of the assay were within ±10%. The stability tests indicate no significant degradation under the conditions of the experiment. This method was used for a phase I study of topical administration of dapaconazole tosylate in healthy human male volunteers.
Assuntos
Antifúngicos/sangue , Cromatografia Líquida de Alta Pressão/métodos , Imidazóis/sangue , Monitoramento de Medicamentos/métodos , Humanos , Limite de Detecção , Masculino , Espectrometria de Massas em Tandem/métodosRESUMO
A rapid, sensitive and specific method to quantify cyproheptadine in human plasma using amitriptyline as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by liquid-liquid extraction using a diethyl-ether/dichloromethane (70/30; v/v) solvent. After removing and drying the organic phase, the extracts were reconstituted with a fixed volume of acetonitrile/water (50/50 v/v)+0.1% of acetic acid. The extracts were analyzed by high performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC-MS/MS). Chromatography was performed isocratically using an Alltech Prevail C18 5 µm analytical column, (150 mm x 4.6 mm I.D.). The method had a chromatographic run time of 4 min and a linear calibration curve ranging from 0.05 to 10 ng/mL (r2 > 0.99). The limit of quantification was 0.05 ng/mL. This HPLC/MS/MS procedure was used to assess the bioequivalence of cyproheptadine in two cyproheptadine + cobamamide (4 mg + 1 mg) tablet formulations (Cobactin® [cyproheptadine + cobamamide] test formulation supplied from Zambon Laboratórios Farmacêuticos Ltda. and Cobavital® from Solvay Farma (standard reference formulation)). A single 4 mg + 1 mg [cyproheptadine + cobamamide] dose of each formulation was administered to healthy volunteers. The study was conducted using an open, randomized, two-period crossover design with a 1-week washout interval. Since the 90% CI for Cmax and AUCs ratios were all within the 80-125% bioequivalence limit proposed by the US Food and Drug Administration, it was concluded that the cyproheptadine test formulation (Cobactin®) is bioequivalent to the Cobavital® formulation for both the rate and the extent of absorption of cyproheptadine.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ciproeptadina/sangue , Ciproeptadina/farmacocinética , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Administração Oral , Adolescente , Adulto , Área Sob a Curva , Estudos Cross-Over , Ciproeptadina/administração & dosagem , Combinação de Medicamentos , Estabilidade de Medicamentos , Feminino , Humanos , Limite de Detecção , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Comprimidos , Equivalência TerapêuticaRESUMO
A rapid, sensitive and specific method for quantifying ciprofibrate in human plasma using bezafibrate as the internal standard (IS) is described. The sample was acidified prior extraction with formic acid (88%). The analyte and the IS were extracted from plasma by liquid-liquid extraction using an organic solvent (diethyl ether/dichloromethane 70/30 (v/v)). The extracts were analyzed by high performance liquid chromatography coupled with electrospray tandem mass spectrometry (HPLC-MS/MS). Chromatography was performed using Genesis C18 4 µm analytical column (4.6 × 150 mm i.d.) and a mobile phase consisting of acetonitrile/water (70/30, v/v) and 1mM acetic acid. The method had a chromatographic run time of 3.4 min and a linear calibration curve over the range 0.1-60 µg/mL (r>0.99). The limit of quantification was 0.1 µg/mL. The intra- and interday accuracy and precision values of the assay were less than 13.5%. The stability tests indicated no significant degradation. The recovery of ciprofibrate was 81.2%, 73.3% and 76.2% for the 0.3, 5.0 and 48.0 ng/mL standard concentrations, respectively. For ciprofibrate, the optimized parameters of the declustering potential, collision energy and collision exit potential were -51 V, -16 eV and -5 V, respectively. The method was also validated without the use of the internal standard. This HPLC-MS/MS procedure was used to assess the bioequivalence of two ciprofibrate 100mg tablet formulations in healthy volunteers of both sexes. The following pharmacokinetic parameters were obtained from the ciprofibrate plasma concentration vs. time curves: AUC(last), AUC(0-168 h), C(max) and T(max). The geometric mean with corresponding 90% confidence interval (CI) for test/reference percent ratios were 93.80% (90% CI=88.16-99.79%) for C(max,) 98.31% (90% CI=94.91-101.83%) for AUC(last) and 97.67% (90% CI=94.45-101.01%) for AUC(0-168 h). Since the 90% CI for AUC(last), AUC(0-168 h) and C(max) ratios were within the 80-125% interval proposed by the US FDA, it was concluded that ciprofibrate (Lipless 100mg tablet) formulation manufactured by Biolab Sanus Farmacêutica Ltda. is bioequivalent to the Oroxadin (100 mg tablet) formulation for both the rate and the extent of absorption.
Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ácidos Fíbricos/farmacocinética , Espectrometria de Massas por Ionização por Electrospray/métodos , Adolescente , Adulto , Feminino , Ácidos Fíbricos/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Espectrometria de Massas em Tandem/métodos , Adulto JovemRESUMO
OBJECTIVE: To assess the comparative bioavailability of two formulations (16 mg tablet) of betahistine (CAS 5579-84-0) in healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, two-period crossover design with a 1-week washout interval. Plasma samples were obtained for up to 36 h post dose. Plasma 2-pyridylacetic acid concentrations were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS) with positive ion electrospray ionization using multiple reaction monitoring (MRM). From the 2-pyridylacetic acid plasma concentration vs. time curves, the following pharmacokinetic parameters were obtained for AUCIast and Cmax. RESULTS: The limit of quantification was 4 ng/mL for plasma 2-pyridylacetic acid analysis. The geometric mean and 90% confidence interval (CI) of test/reference percent ratios were: 98.94% (92.21%-106.16%) for Cmax, 95.42% (91.74%-99.25%) for AUClast. CONCLUSION: Since the 90% CI for Cmax and AUCs ratios were all within the 80-125% interval proposed by the US Food and Drug Administration Agency, it was concluded that the test formulation is bioequivalent to the reference for both the rate and the extent of absorption.