Chemometric-Assisted Spectrophotometric Method for the Simultaneous Determination of Ciprofloxacin and Doxycycline Hyclate in Pharmaceutical Formulations

Table 2

Composition of validation set and predicted results obtained in synthetic mixtures by PCR and PLS methods.

CIP	DOX	PCR				PLS
		CIP		DOX		CIP		DOX
Actual conc. (μg/mL)		Predicted (μg/mL)	% recovery	Predicted (μg/mL)	% recovery	Predicted (μg/mL)	% recovery	Predicted (μg/mL)	% recovery
5	13	4.99	99.72	12.96	99.69	4.99	99.73	12.96	99.66
7	10	7.04	100.60	10.00	100.00	7.04	100.61	10.01	100.05
5	7	5.09	101.75	7.00	100.00	5.09	101.76	7.00	100.00
7	7	7.18	102.60	7.09	101.29	7.18	102.61	7.09	101.30
7	13	7.03	100.50	13.23	101.77	7.04	100.52	13.23	101.79
5	10	4.95	98.95	9.90	99.00	4.95	98.96	9.90	99.00
3	7	2.72	90.52	6.68	95.43	2.72	90.55	6.68	95.40
3	13	2.88	95.98	12.70	97.69	2.88	96.00	12.70	97.66
3	10	2.79	92.88	9.65	96.50	2.79	92.89	9.65	96.49
R^2		0.998		0.994		0.998		0.994
Intercept		0.376		0.210		0.379		0.210
Slope		0.932		0.988		0.931		0.988
RMSECV		0.278		0.794		0.283		0.824
RMSEP		0.142		0.219		0.143		0.208

R², correlation coefficient; RMSECV, root-mean-square error of cross-validation; RMSEP, root-mean-square error of prediction.