Redox-Reaction Based Spectrophotometric Assay of Isoniazid in Pharmaceuticals

Table 5

Results of recovery study via standard addition method with tablet.

Method	Tablets studied	INH in; tablet; µg mL^−1	Pure; INH; Added; µg mL^−1	Total; Found; µg mL^−1	Pure INH recovered*; percent ± SD
A	Isokin-300	2.96	1.5	4.41	99.28±2.03
		2.96	3.0	6.01	100.9±3.12
		2.96	4.5	7.56	101.3±2.99
B	Isokin-300	1.01	0.5	1.51	99.85±2.25
		1.01	1.0	2.04	101.3±2.32
		1.01	1.5	2.55	101.7±3.14

∗Mean value of three determinations.