Principles of White Analytical Chemistry and Design of Experiments to Development of Stability-Indicating Chromatographic Method for the Simultaneous Estimation of Thiocolchicoside and Lornoxicam.

Background: A variety of chromatographic methods have been published for the stability evaluation of thiocolchicoside (THC) and lornoxicam (LNX). Nevertheless, the development of chromatographic methods requires the use of neurotoxic and teratogenic organic solvents that are detrimental to the environment and harmful to human life.

Objectives: Using the principles of design of experiments (DoE), a novel white analytical chemistry-driven stability-indicating high-performance thin-layer chromatographic (SI-HPTLC) method has been developed for the concurrent stability study of THC and LNX. To protect the environment and human life, the stability-indicating HPTLC method was developed using safe organic solvents.

Method: Potential analytical method risk parameters (AMRPs) and analytical method performance attributes (AMPAs) were screened using the fractional factorial design. The response surface analysis and optimization of critical AMRPs and AMPAs was carried out using full factorial design. Navigation of the method operable design region (MODR) was used to develop the SI-HPTLC technique. The developed method was validated in accordance with the International Council for Harmonization (ICH) Q2 (R1) guideline.

Results: The developed method's greenness was evaluated using the AGREE (Analytical Procedure Greenness) tool and ESA (Eco-Scale Assessment). The Blue (B) model was used to assess the proposed method's cost and time efficiency and user-friendliness. For the stability studies of THC and LNX, the 12 principles of WAC (white analytical chemistry) were used to evaluate the published and proposed chromatographic techniques.

Conclusions: Compared to previously published chromatographic techniques for studying the stability of THC and LNX, the suggested approach was found to be more affordable, environmentally friendly, and user-friendly.

Highlights: The development of a stability-indicating HPTLC method using a novel white analytical chemistry approach and organic solvents with low toxicity potential. Application of the developed method for analysis of the forced degraded sample and fixed-dose combinations of THC and LNX.