Application of a Stability-Indicating HPTLC Method for Simultaneous Quantitative Determination of Olmesartan Medoxomil and Hydrochlorothiazide in Pharmaceutical Dosage Forms

Table 1

Linearity parameters for calibration curve.

Parameter	Olmesartan medoxomil	Hydrochlorothiazide
Retention factor (𝑅𝑓)	0.29	0.52
Linearity range (ng/band)	80–480	25–150
Regression equation (𝑦=𝑚𝑥+𝑏)	𝑦=1.32𝑥+0.95	𝑦=3.54𝑥+1.02
Correlation coefficient (𝑟)	0.9996	0.9999
Limit of detection (ng/band)	18.12	6.31
Limit of quantification (ng/band)	56.35	18.56
Standard deviation of slope^a (𝑆𝑎)	0.9813	0.9012
Standard deviation of intercept^a (𝑆𝑏)	1.2013	1.1430
Regression coefficient (𝑟^2)	0.999	0.998
Peak purity index (𝑃)	0.9986	0.9995
Method precision^a (RSD %)	0.92	0.84

^aMean of five replicates, RSD: relative standard deviation.