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Ion selective electrodes, potentiometry, and potentiometric titrations.

A rapid and precise continuous-flow method is described for the determination of isoniazid (0050–200 µg ml–1) based on the chemiluminescence produced during its reaction with N-bromosuccinimide in alkaline medium The emission intensity is greatly enhanced by the presence of ammonia The procedure is automated and samples can be analysed at a rate of 112 solutions per hour with a relative error of about 2% When applied to tablets, the method is relatively free from interferences from common excipients and co-existing compounds The results obtained for the assay of commercial preparations compared well with those obtained by an official chemical method and demonstrated good accuracy and precision

Continuous-flow chemiluminescence determination of isoniazid by oxidation with N-bromosuccinimide

Flow injection determination of isoniazid using N-bromosuccinimide- and N-chlorosuccinimide-luminol chemiluminescence systems.

Novel approach to reaction-rate based determinations by use of transient redox effects

Comparison of Analysis of Isoniazid and its Dosge Forms by Several Methods

A potentiometric procedure for the assay of isonicotinic acid hydrazide (isoniazid) with vanadium(V) at room temperature is described. The reduction of vanadium(V) to vanadium(IV) by isoniazid in an acidic medium is catalysed by osmium tetroxide, and the application of this method to the assay of isoniazid in pharmaceutical preparations is considered. Oxalic acid interferes in the determination, although commonly used excipients such as starch, dextrin, sucrose, glucose, lactose and gum acacia do not interfere.

G. Bala Bhaskara Rao

Papers

A potentiometric procedure for the assay of isonicotinic acid hydrazide (isoniazid)