Sequential Spectrophotometric Method for the Simultaneous Determination of Amlodipine, Valsartan, and Hydrochlorothiazide in Coformulated Tablets

Table 3

Statistical comparison for the results obtained by the proposed spectrophotometric method and the reported method [23] for the analysis of AML, VAL, and HCT in Exforge HCT tablets.

Value	Proposed method			Reported method^a
	AML	VAL	HCT	AML	VAL	HCT
Mean	100.37	99.90	99.61	100.21	100.23	100.03
SD	1.252	1.015	1.141	0.733	0.730	0.693
RSD%	1.247	1.016	1.145	0.731	0.728	0.693
𝑛	9	9	9	9	9	9
Variance	1.567	1.030	1.302	0.537	0.533	0.480
Student’s 𝑡 test^b	0.343 (2.16)	0.788 (2.131)	0.927 (2.16)	—	—	—
𝐹 value^b	2.921 (3.438)	1.933 (3.438)	2.710 (3.438)	—	—	—

aHPLC method using Luna C₁₈ column, a mobile phase consisting of methanol-phosphate buffer (30 mM, pH 5.5) (62 : 38 by volume) at a flow rate of  1 mL/min, and UV detection at 234 nm.
bThe values in the parenthesis are the corresponding theoretical values of  𝑡 and 𝐹 at  𝑃=0.05.