Spectrophotometric determination of procaine hydrochloride by means of iron (3+)-4-aminobenzohydroxamic acid complex.
A rapid, simple and reproducible method is presented, for the determination of procaine hydrochloride in bulk and in pharmaceutical preparations containing also corbadrine or caffeine. The method is based on the conversion of procaine into the corresponding hydroxamic acid which reacts with iron (III) forming a complex of violet colour stable at pH 2.0, with a maximum absorption at a wavelength of 540 nm, and with molar absorptivity (epsilon = 0.43 X 10(3) l mol-1 cm-1). The minimum detectable amount was 1.47 X 10(-4) M/l, and Lambert-Beer law is obeyed in the range 2.93 X 10(-4) - 4.106 X 10(-3) M/l. By the application of Bent-French method it has been established that the stoichiometric ratio of 4-aminobenzohydroxamic acid and iron (3+) in the complex is 3:1. No interference with degradation product of procaine (4-aminobenzoic acid) was observed.
Novaković
J
J
Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Belgrade, Yugoslavia.
D005290:Ferric Compounds / Q000032:analysis*; D006877:Hydroxamic Acids / Q000032:analysis*; D007202:Indicators and Reagents; D011343:Procaine / Q000032:analysis*; D013056:Spectrophotometry, Ultraviolet
D005290:Ferric Compounds; D006877:Hydroxamic Acids; D007202:Indicators and Reagents; C065269:iron(3+)-4-aminobenzohydroxamic acid complex; D011343:Procaine