Assessment of Eco-Whiteness and Green Analytical Profiles of Microfluidic Paper Analytical Device and Spectrophotometric Methods for the Determination of Olanzapine in Pharmaceuticals

Abstract

This study presents the development and validation of three analytical methods for estimating the antipsychotic drug olanzapine (OLP) in pharmaceutical preparations. The first method is a conventional spectrophotometric technique based on a redox reaction between olanzapine and ferric chloride, followed by complexation with potassium ferricyanide, which produces Prussian blue with an absorption peak at 717 nm. In parallel, two microfluidic paper analytical device (µPAD) platforms were fabricated using wax printing with two different designs, enabling miniaturized, low-cost, and environmentally friendly modifications of the same colorimetric reaction. The spectrophotometric method (Method I) showed excellent linearity within the range of 0.1–10 μg/mL, with a limit of detection (LOD) of 0.03 μg/mL. The µPAD methods (Methods II and III) showed linear ranges of 0.5–5 and 1–5 μg/mL, with LODs of 0.3 and 0.26 μg/mL, respectively. All methods demonstrated satisfactory precision (RSD < 2%). The greenness of the methods was evaluated using various assessment tools, including the analytical eco-scale, ChlorTox, analytical GREEnness (AGREE) metrics, and AGREEprep. The results showed an excellent greenness profile, and white analytical chemistry was also evaluated by the Red-Green-Blue 12 algorithm, which gave excellent whiteness scores above 85 for all methods. The proposed µPAD systems offer an environmentally friendly, portable, and highly reproducible alternative for point-of-care or on-site drug analysis. The results of this investigation showed that OLP in dosage forms may be reliably assessed using the suggested methods.