Background: PARTIAL Least Squares (PLS) and Principal Component Regression (PCR)
are two well-known chemometric methods based on dimension reduction techniques. They can be very
practical analyzing a large data set of multiple correlated predictor variables.
Objective: In the presented work, the resolving power of spectrophotometric assisted mathematical
techniques was implemented for the simultaneous determination of two active ingredients; Ephedrine
Hydrochloride (EPH) and naphazoline nitrate (NAPH), in a matrix of excipients.
Methods: To build the PLS and PCR models, a calibration set was prepared where the two drugs, in
combination with the interfering parabens, were modeled by multilevel multifactor design. The proposed
models successfully predicted the concentrations of both drugs in validation samples with low
Root Mean Squared Error of Prediction (RMSEP).
Results: The results revealed the ability of the mentioned multivariate calibration models to analyze
EPH and NAPH in the presence of the interfering parabens with high selectivity in the concentration
ranges of 4.00-20.00 μg mL-1 and 1.00-9.00 μg mL-1, respectively.
Conclusion: A commercially available nasal spray was successfully analyzed using the developed
methods without interfering with other dosage form additives.