Development and Validation of a Versatile UPLC-PDA Method for Simultaneous Determination of Paracetamol, Tizanidine, Aceclofenac, and Nimesulide in Their New Combinations

Table 6

Application of the UPLC method for the determination of the studied drugs in laboratory-prepared mixtures.

Mixture number	Concentration taken (µg·mL^−1)				Concentration found (µg·mL^−1)				% recovery
	PAR	TIZ	ACF	NIM	PAR	TIZ	ACF	NIM	PAR	TIZ	ACF	NIM
1	162.5	2.0	100.0	50.0	162.42	2.02	98.98	50.90	99.95	101.00	98.98	101.80
2	81.25	1.0	50.0	100.0	81.54	0.985	49.36	98.01	100.36	98.50	98.72	98.01
3	162.5	1.0	50.0	50.0	160.99	0.972	49.59	48.87	99.07	97.20	99.18	97.74
4	243.75	2.0	—	75.0	241.88	1.96	—	73.99	99.23	98.00	—	98.65
5	325.0	2.0	—	100.0	322.76	1.99	—	100.23	99.31	99.50	—	100.23
6	100.0	—	—	100.0	97.88	—	—	97.41	97.88	—	—	97.41
7	162.5	—	—	50.0	159.62	—	—	49.77	98.23	—	—	99.54
8	—	3.5	50.0	—	—	3.37	51.33	—	—	96.29	102.66	—
9	—	2.0	100.0	—	—	1.92	97.75	—	—	96.00	97.75	—
								Mean	99.15	98.07	99.46	99.05
								SD	0.875	1.781	1.872	1.573
								RSD	0.877	1.821	1.882	1.588

Average of three determinations.