Method Development for Simultaneously Determining Indomethacin and Nicotinamide in New Combination in Oral Dosage Formulations and Co-Amorphous Systems Using Three UV Spectrophotometric Techniques
Table 1
Analytical performance data for the proposed methods.
Parameter
Indomethacin
Nicotinamide
Method
ZCD2
DWD1
SS
ZCD2
DWD1
RS
Wavelength (nm)
318.0
264.5–275.0
268.0
276.5
254.0–266.0
261.5
Linearity range (μg/mL)
2.5–50.0
2.5–40.0
2.5–40.0
2.5–50.0
2.5–50.0
2.5–60.0
Determination coefficient
0.9998
0.9997
0.9997
0.9997
0.9999
0.9999
Slope
0.00324
0.00761
0.04292
0.01681
0.01602
0.02367
Intercept
0.00015
0.00179
0.00051
0.00029
0.00190
−0.00524
SD of slope
0.00002
0.00006
0.00032
0.00010
0.00007
0.00008
SD of intercept
0.00040
0.00127
0.00694
0.00268
0.00183
0.00255
95% confidence range of slope
(0.00321–0.00328)
(0.00747–0.00775)
(0.04215–0.04369)
(0.01658–0.01705)
(0.01586–0.01619)
(0.02349–0.02386)
95% confidence range of intercept
(−0.00081–0.00110)
(−0.00131–0.00489)
(−0.01646–0.01749)
(−0.00604–0.00663)
(−0.00243–0.00623)
(−0.01112–0.00064)
LOD (μg/mL)
0.41
0.55
0.53
0.53
0.38
0.36
LOQ (μg/mL)
1.25
1.66
1.62
1.59
1.14
1.08
System suitability
0.77
0.33
0.15
0.83
0.23
0.41
The range is represented by lower limit–upper limit. RSD% of six repetitions of concentration of 20 μg/mL for each of IND and NCT.