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

Table 2

Results of accuracy.

Recovery study level	Replicate	Quantity Siloflam tablet powder (containing 37.94% sildenafil citrate) (mg)	Quantity of paracetamol (purity 99.7%) (mg)	Found R value of mixture (%)	Sildenafil citrate recovery (mg)	Recovery rate (%)	Mean recovery, RSD (%)
1; (R value about 35%)	1	180.46	131.07	34.41	68.54	100.1	100.1
	2	180.35	131.52	34.06	67.74	99.0
	3	180.53	131.64	33.86	67.18	98.1
	4	184.16	129.62	35.44	70.95	101.6
	5	181.18	130.13	34.93	69.63	101.3
	6	182.42	130.21	34.90	69.58	100.5	1.3
2; (R value about 50%)	1	268.15	99.28	51.02	103.10	101.3	100.6
	2	268.38	99.25	50.97	102.86	101.0
	3	266.25	99.06	50.93	102.51	101.5
	4	268.92	99.33	51.02	103.16	101.1
	5	263.55	100.29	49.72	98.89	98.9
	6	267.32	99.74	50.38	100.96	99.5	1.1
3; (R value about 65%)	1	335.69	71.68	64.15	127.88	100.4	99.8
	2	334.62	71.22	63.77	124.96	98.4
	3	339.25	69.43	65.45	131.14	101.9
	4	337.47	71.51	64.00	126.77	99.0
	5	334.18	71.56	63.87	126.10	99.5
	6	335.22	71.89	63.86	126.64	99.6	1.2