Development and Validation of a Simple, Green Infrared Spectroscopic Method for Quantitation of Sildenafil Citrate in Siloflam Tablets of Unknown Manufacturing Formula

Table 4

Results of quantitation on batch N531.

Replicates	Sample weight (mg)	Paracetamol weight (mg, purity: 99.7%)	Calculated R value (%)	Mass content of sildenafil in tablet (%, m/m)
1	267.28	100.08	49.95	37.3
2	269.33	100.21	50.88	38.4
3	270.14	100.13	50.53	37.7
4	269.66	100.22	50.86	38.3
5	268.47	100.37	50.36	37.8
6	268.35	100.04	51.06	38.8
Average (1–6)				38.1
RSD (%) (1–6)				1.4