Development of Sensitive Analytical (RP-HPLC-PDA, UV/VIS) Method for the Determination of N-Isonicotynoyl-N′-(2-Fluorobenzal)Hydrazone in Aqueous Phase

The stability and quality of pharmaceutical substances are assured by systematic evaluation using various analytical techniques. Biologically active compounds retain and exhibit maximum potency during their shelf life. Once the drug expiry period is crossed, deterioration, decrease of therapeutic activity, and increased toxicity can occur. The purpose of the present study was to develop a simple, rapid and reproducible analytical method for the determination of N-isonicotynoyl-N′-(2-fluorobenzal)hydrazone – a synthesized by us halogenated isoniazid derivative with high tuberculostatic activity – in aqueous phase, on the basis of RP-HPLC-PDA and UV/VIS spectrophotometry investigations. The proposed RP-HPLC-PDA procedure is characterized by short retention time (3.1 min), high precision (RSD < 3.52%), and good linearity (R 2 > 0.9941). HPLC patterns display well-resolved peaks without interference. Despite high linearity (R 2 = 0.9978) of the UV/VIS spectrophotometry, greater LOQ and LOD values indicated unsuitability of this method for the detection and quantification of N-isonicotynoyl-N′-(2-fluorobenzal)hydrazone at low concentrations (< 10 μg/mL).