Development and validation of a novel analytical approach based on 2D diffuse light reflection for the quantitative determination of ribavirin in aqueous solutions

Aim: In the present work, an original analytical approach based on two-dimensional diffuse reflectance spectroscopy is proposed for the quantitative determination of ribavirin (RBV) in aqueous solutions with different hydrogen isotopic composition. Materials and methods: The proposed approach is based on the kinetics of diffuse light reflection from a heterogeneous sample surface, followed by chemometric processing of dynamic speckle patterns. Mathematical descriptors analogous to those used in QSAR approaches were calculated and used as analytical parameters, including Wiener (W) and Balaban (J) indices in the Trinajstić modification: d₁, d₂, d₃, as well as two triads of standard deviations sd₁, sd₂, sd₃; r₁, r₂, r₃ (ri = di/sdi). Ribavirin is a synthetic nucleoside analogue with pronounced antiviral activity and acts as an antimetabolite. Results: A correlation was established between the calculated descriptors and ribavirin concentration in the studied aqueous solutions with variations in hydrogen isotopic composition: for BD (r = 0.982) and for DDW (r = 0.997). It was shown that the isotopic composition of water significantly affects the characteristics of the analytical signal, while the use of DDW as a solvent provides higher linearity. The precision of the method is characterized by RSD values of about 7% under repeatability conditions. Conclusion: The obtained results demonstrate the applicability of the analytical approach based on 2D diffuse reflectance in pharmaceutical analysis for the quantitative determination of drug substances in aqueous media. The proposed method is characterized by rapidity, universality, and potential for further development of cost-effective non-destructive analytical control techniques.