Novel Reagents for the Spectrophotometric Determination of Isoniazid

Abstract

Isoniazid is an antitubercular drug, widely used for tuberculosis. Owing to its importance in therapeutics, the present study aims to develop simple method for the spectrophotometric determination of isoniazid (INH). Two novel reagents, epichlorohydrine (ECH) and 4-hydroxyphenaylchloride (HPC) are used for the spectrophotometric determination of INH. Based on the nucleophilic substitution reactions of INH with EPI & HPC in basic medium, rapid, simple, inexpensive, precise, and accurate visible spectrophotometric method is proposed for the determination of INH in bulk drug and in formulations. Method involves the reaction of INH with EPI and HPC in basic medium to form yellow-colored chromogen, measuring the absorbances at 405 and 402 nm for INH-EPI & INH-HPC, respectively. The optimum experimental conditions have been studied. The absorbance was found to increase linearly with the concentration of the drug and formed the basis for quantification. The calibration graphs were linear from 2.00–22.00 μg mL−1and 20.00–120.00 μg mL−1for INH-EPI & INH-HPC, respectively. The apparent molar absorptivity and Sandell's sensitivity are calculated to be0.51×104&0.10×104 L mol−1 cm−1and 0.027 & 0.134 μg cm−2for INH-EPI & INH-HPC, respectively. The procedure is used to determine INH in pharmaceutical products. The associated pharmaceutical materials do not interfere in the measurements.

Electrochemical and Spectroscopic Characteristics of Artemisinin Antimalarial Drug: Charge Transfer Redox Process

“…and ). The molar absorptivity of artemisinin was 2877.6 mol −1 cm −1 L, which is close to that of similarly related compounds . All measurements here were made at room temperature (23°C).…”

Simultaneous Spectrophotometric Estimation of Artesunate and Mefloquine

“…41 to give the stock solution containing 1000 g/mL of ART and 2000 g/mL of MEF. Various dilutions of the tablet stock solutions were scanned and the absorbance of these solutions were measured at 240 nm and 222 nm, respectively, and the concentrations of the two drugs in the sample solutions were calculated using (1) and (2). e analysis procedure was repeated six times.…”

Two new spectrophotometric methods for the determination of isoniazid in bulk form and tablet dosage form

“…Apart from the use of derivative spectroscopy and partial least squares 16,17 , the majority of spectrophotometric methods for the quantification of isoniazid takes advantage of the varied functionality and moderate reactivity of the drug which also serve to improve sensitivity and selectivity of the resulting methods. Thus, isoniazid because of its activated amino pyridine skeleton, has been used as coupling agents with diazotized reagents such as dapsone and 1-amino anthraquinone zinc chloride 18,19 ; in Schiff base formation with cis-cinnamaldehyde 20 , 4-dimethylaminocinnamaldehyde 21 and as substrate for nucleophilic substitution reactions with epichlorohydrine and 4-hydroxyphenaylchloride 22 . The donor capability of the drug has also been employed in charge-transfer complexation with various acceptors including chloranil, bromanil 23 etc.…”