B. Gala et al., DIRECT KINETIC DETERMINATION OF BROMHEXINE HYDROCHLORIDE IN PHARMACEUTICAL FORMULATIONS, Analytical letters, 26(12), 1993, pp. 2607-2617
A very simple, automatic, fast method for the photometric determinatio
n of bromhexine hydrochloride based on the application of kinetic meth
odology and the stopped-flow mixing technique to the coupling reaction
between the diazotized bromhexine derivative and (N-(1-naphthyl)ethyl
enediamine is proposed. The high initial rate of this reaction allows
analytical measurements to be made within only 0.5-1 s, which makes th
e method applicable to automatic routine analyses. The calibration gra
ph is linear over the range 1.5-65.0 mug mL-1 and the precision (as %R
SD) is less than 2%. The presence of antibiotics such as penicillins a
nd cephalosporins in a 100-fold excess has no effect on the analyte de
termination. The proposed method was satisfactorily used for direct an
alysis of pharmaceutical formulations containing these antibiotics.