Application of Cerium (IV) as an Oxidimetric Agent for the Determination of Ethionamide in Pharmaceutical Formulations

Table 5

Results of recovery experiment through standard-addition method.

Method	Tablet studied	ETM in tablet (mg; μg/mL)	Pure ETM; added (mg; μg/mL)	Total found (mg; μg/mL)	Pure ETM; recovered (percent ± SD)
Titrimetry	Ethide 250	2.99; 2.99; 2.99	1.5; 3.0; 4.5	4.55; 5.92; 7.48	101.43 ± 1.42; 98.97 ± 0.84; 100.11 ± 0.68
Spectrophotometry	Ethide 250	1.51; 1.51; 1.51	0.75; 1.50; 2.25	2.33; 3.21; 3.82	103.22 ± 2.44; 104.82 ± 2.53; 102.14 ± 2.35

Mean value of three determinations.