Table 1 Linear regression and system suitability parameters for the simultaneous determination of the drugs under study using the proposed HPLC method

Flow rate (mL/min)

1.00

1.00

1.00

1.00

Retention time (min) ± RSD

1.45 ± 0.06

2.29 ± 0.08

4.68 ± 0.06

6.11 ± 0.16

Resolution (Rs) (> 2)*

–

2.95

9.89

4.33

Selectivity factor ( ∝) (≥ 1)*

2.07

2.85

1.94

1.77

Tailing factor (T) (≤ 2)*

1.19

1.12

1.09

1.11

Linearity range (μg/mL)

10–200

10–200

10–200

10–200

Linearity equation

Y = 5446 X + 11,558

Y = 20,459 X − 30,059

Y = 26,631 X − 6047.4

Y = 27,127 X − 29,402

R²

0.9998

0.9998

0.9998

0.9999

Accuracy (%R ± RSD) (n = 3)

98.39 ± 1.23

99.97 ± 0.76

100.35 ± 0.66

99.80 ± 1.07

LOD (μg mL⁻¹)

2.38

2.01

2.00

2.42

LOQ (μg mL⁻¹)

7.20

6.09

6.07

7.34