Estimation of Tadalafil Using Derivative Spectrophotometry in Bulk Material and in Pharmaceutical Formulation

Table 2

Accuracy studies.

Drug	Methods	Initial amount  [𝜇g/mL]	Amount added  [𝜇g/mL]	Amount recovered  [𝜇g/mL, 𝑛=3]	% Recovered	% RSD
Tadalafil	A	10	8	18.07	100.91	0.52
		10	10	20.16	101.63	0.65
		10	12	22.13	101.11	0.47
	B	10	8	18.06	100.75	0.89
		10	10	20.10	101.06	1.22
		10	12	22.06	100.50	0.29
	C	30	24	54.13	100.54	0.18
		30	30	60.13	100.44	0.16
		30	36	66.06	100.16	0.19
	D	30	24	54.11	100.48	0.16
		30	30	60.10	100.35	0.12
		30	36	66.07	100.21	0.29

𝑛: number of estimations.