Application of capillary zone electrophoresis to determine second-generation H1 antihistaminic drugs, loratadine and rupatadine

Abstract The second generation of H1 antihistamines from the piperidine group are often used for treating allergic diseases due to their action on histaminic receptors, the primary mediator of allergy. Moreover, the antihistamines have anti-inflammatory action, mediated through platelet-activating factor blocking activity. A simple and rapid capillary zone electrophoresis method was developed and validated for the determination of loratadine (LOR) and rupatadine (RUP) in tablets. The analyses were carried out using a fused silica capillary of 50.2 cm (40 cm effective length), 75 µm i.d. The background electrolyte was composed of boric acid 35 mmol/L, pH 2.5. Voltage of 20 kV, hydrodynamic injection of 3447.3 Pa for 3s, temperature at 25 ºC, and UV detection at 205 nm were applied. Electrophoretic separation was achieved at 1.8 and 2.8 min for RUP and LOR, respectively. The method was linear for both drugs in a range of 50.0 to 400.0 µg/mL (r>0.99). The limits of detection and quantification were 46.37 and 140.52 µg/mL, for LOR and 29.60 and 89.69 µg/mL for RUP respectively. The precision was less than 5.0 % for both drugs. The average recovery was approximately 100 %. The proposed novel method can significantly contribute to the rapid detection of counterfeit products and in quality control of drug products containing antihistamines

Simultaneous determination of ethinyl estradiol and drospirenone in oral contraceptive by high performance liquid chromatography

A simple, rapid, economical and reliable high performance liquid chromatographic method has been developed and successfully applied in simultaneous determination of ethinyl estradiol and drospirenone in coated tablets. The HPLC method was performed on a LiChroCART® 100RP column (125x4 mm i.d., 5 µm) with acetonitrile:water 50:50 (v/v) as mobile phase, pumped at a flow rate of 1.0 mL.min-1. The fluorescence detection for ethinyl estradiol was made at λex= 280 nm and λem= 310 nm and a UV detection for drospirenone was made at 200 nm. The elution time for ethinyl estradiol and drospirenone were 4.0 and 5.7 min, respectively. The method was validated in accordance to USP 34 guidelines. The proposed HPLC method presented advantages over reported methods and is suitable for quality control assays of ethinyl estradiol and drospirenone in coated tablets.

Um método simples, rápido, econômico e confiável foi desenvolvido empregando a cromatografia líquida de alta eficiência para a determinação simultânea de etinilestradiol e drospirenona em comprimidos revestidos. O método foi realizado utilizando coluna LiChroCART® 100RP (125 x 4 mm d.i., 5 µm), a fase móvel constituída de acetonitrila:água, 50:50 (v/v) com vazão de 1,0 mL.min-1. A detecção foi realizada empregando fluorescência em λex= 280 nm e λem= 310 nm para o etinilestradiol e na região de UV em 200 nm para a drospirenona. O etinilestradiol e a drospirenona tiveram tempo de retenção de 4,0 e 5,7 min, respectivamente. O método foi validado de acordo com as diretrizes da USP 34. O método proposto apresentou vantagens sobre os relatados na literatura e pode ser considerado adequado para o controle de qualidade do etinilestradiol e da drospirenona em comprimidos revestidos.