AQbD integrated High-Performance Thin Layer Chromatographic Method for Quantitative Estimation of Tavaborole in the presence of its degradants and the matrix of nanostructured lipid carriers

Background: Tavaborole (TAV), a benzoxaborole derivative, is an FDA-approved antifungal agent for treating onychomycosis, a common and persistent fungal infection of the toenails.

Objective: This study aimed to develop a robust stability-indicating HPTLC method to determine TAV in nanostructured lipid carriers (NLC) using a comprehensive approach that includes risk assessment, and Analytical Quality by Design.

Methods: The critical method parameters influencing the HPTLC results were screened using a Placket-Burman screening design followed by its optimization using a central composite optimization design. The developed method was validated as per ICH recommendation.

Results: Optimized method utilized pre-coated aluminum-backed HPTLC plates using 10 µL/band injection volume, and the plate was developed using an isocratic mobile phase consisting of toluene: ethyl acetate: formic acid (75:25:1%v/v/v) in twin trough chamber pre-saturated for 20 mins with vapors of 10 mL of mobile phase. The separated components were detected at a wavelength of 221 nm. The developed HPTLC method resulted in a retardation factor of 0.49 ± 0.04 for TAV. Validation results revealed the HPTLC method's specificity (peak purity ≥ 0.999), linearity over a concentration range of 2-10 μg/band, sensitivity (LOD 0.209 μg and LOQ 0.635 μg), accuracy (99.68 - 101.43%w/w), and precision (%RSD < 2.0).

Conclusion: The developed robust stability-indicating HPTLC method was successfully implemented for the sustainable testing of the TAV in the NLC formulations and stability testing.