Sensitive Spectrophotometric Determinations of Paracetamol and Protriptyline HCl Using 3-Chloro-7-hydroxy-4-methyl-2H-chromen-2-one

Table 1

Spectral and statistical data for the determination of drugs.

Parameters	Drugs
	PCT	PTP
𝜆max (nm)	545	468
Beer’s law limits (µg/mL)	10.00–60.00	40.00–160.00
Molar absorptivity (L mol^−1 cm^−1)	0.12 × 10^4	0.55 × 10^4
Sandell’s sensitivity (µg cm^−2)	0.11 × 10^−2	0.54 × 10^−2
Limit of detection* (µg mL^−1)	0.0578	0.1527
Limit of quantification* (µg mL^−1)	0.1753	0.5840
Regression equation**	𝑌=𝑎+𝑏𝑋	𝑌=𝑎+𝑏𝑋
Slope (𝑏)	0.0065	0.0017
Intercept (𝑎)	0.0280	0.0025
Correlation coefficient (𝑟)	0.9963	0.9994

∗Limit of detection calculated according to ICH guidelines.
 ^∗∗𝑌 is the absorbance and 𝑋 concentration in µg mL⁻¹.