ASSAY OF ISONIAZID UTILIZING ISOCRATIC HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Ronald Bartzatt*, Nagat Mohamed, Carolyn Fochek, Alyna Nguyen and Purnima Gajmer

ABSTRACT

Isoniazid is a first-line drug for the treatment of tuberculosis. Isoniazid is considered a small molecule drug, having molar mass of 137.1 grams per mole. This drug has a pyridine ring, carbonyl carbon, and hydrazide functional group. The drug isoniazid was identified and assayed from aqueous based mixtures, these include mixtures having: 1) Water, 1% (v/v) ethanol, and 0.174 molar acetic acid; 2) Normal saline (0.9%) mixtures; and 3) Mixtures having cellulose and/or starch as excipients. The standard curve ranged from 6.4521 x 10-5 molar isoniazid to 4.6917x 10-3 molar isoniazid (a 73-fold range in concentration). The dead volume for this instrumentation is 1.5 mL. The dead time is 1.5 minutes, with isoniazid eluting at 2.8 minutes. The limit of quantitation (LOQ) is 3.3461 x 10-4 molar, with limit of detection (LOD) of 1.0038 x 10-4 molar isoniazid. The drug isoniazid was successfully identified and assayed from normal saline mixtures and aqueous dissolved mixtures have cellulose and starch for analogy to excipients of tablet and capsule pharmaceutical preparations. The assay of isoniazid using isocratic high performance liquid chromatography will be useful for the quality control monitoring within pharmaceutical manufacturing, following and verification for patient compliance, confirmation of drug presence in various other medicinal formulations, and assay method for averting adulterants.

Keywords: Isoniazid, tuberculosis, HPLC, high performance liquid chromatography.