RESUMO
This paper reports for the first time, a method for simultaneous determination of naphazoline (NPZ) and zinc (Zn) using an analytical separation technique (capillary electrophoresis with capacitively coupled contactless conductivity detection -CE-C4D). A single run is possible every 55s (sampling rate=65h-1). The separation by CE-C4D was achieved on a fused silica capillary (50cm length - 10cm effective, 50µm i.d.) with a background electrolyte (BGE) composed by 20mmolL-1 of 2-(morpholin-4-yl)ethane-1-sulfonic acid (MES) and 20mmolL-1 of histidine (HIS) (pH 6.0). Detection limits were estimated at 20 and 30µmolL-1 and recovery values for spiked samples were 98 and 102% for NPZ and Zn, respectively. The developed procedure was compared to HPLC (NPZ) and FAAS (Zn) and no statistically significant differences were observed (95% confidence level).
Assuntos
Eletroforese Capilar/métodos , Nafazolina/análise , Zinco/análise , Cromatografia Líquida de Alta Pressão , Capacitância Elétrica , Condutividade Elétrica , Eletrólitos/química , Limite de DetecçãoRESUMO
A capillary zone electrophoresis (CZE) method has been developed to separate and quantitate naphazoline (NAPH), dyphenhydramine (DIP) and phenylephrine (PHE) in nasal solutions. Samples were diluted 1:25 in ultrapure water and injected at the anodic end. A central composite design has been used to optimise the experimental conditions for a complete and fast separation of the active ingredients studied. Critical parameters such as voltage, pH and buffer concentration have been studied to evaluate how they affect responses such as resolution and migration times. Separation was performed on a silica capillary with 75 microm I.D. and 70 cm total length at an applied voltage of 17.7 kV with a phosphate run buffer of pH 3.72 and 0.063 mol l(-1). Calibration curves were prepared for NAPH, DIP and PHE. For each analyte, the correlation coefficients were >0.999 (n=15). The RSD% of six replicate injections for each analyte were reasonably good. The method was applied to the quantitation of the three components in a commercial dosage form. The proposed method has the advantage of needing a very simple sample pretreatment and being faster than a typical HPLC chromatographic method.
Assuntos
Difenidramina/análise , Nafazolina/análise , Fenilefrina/análise , Administração Intranasal , Algoritmos , Eletroforese Capilar , Excipientes , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Soluções Farmacêuticas , Reprodutibilidade dos Testes , Espectrofotometria UltravioletaRESUMO
The complementary use of partial least-squares (PLS) multivariate calibration and artificial neural networks (ANNs) for the simultaneous spectrophotometric determination of three active components in a pharmaceutical formulation has been explored. The presence of non-linearities caused by chemical interactions was confirmed by a recently discussed methodology based on Mallows augmented partial residual plots. Ternary mixtures of chlorpheniramine, naphazoline and dexamethasone in a matrix of excipients have been resolved by using PLS for the two major analytes (chlorpheniramine and naphazoline) and ANNs for the minor one (dexamethasone). Notwithstanding the large number of constituents, their high degree of spectral overlap and the occurrence of non-linearities, rapid and simultaneous analysis has been achieved, with reasonably good accuracy and precision. No extraction procedures using non-aqueous solvents are required.