Validation of spectrophotometric and colorimetric method for the specific quantification of sofosbuvir From luminar capsule microneedle in liver tissue through ex vivo and in vivo applications

An antiviral prodrug that has received regulatory approval and primarily employed in the treatment of hepatitis C is sofosbuvir (SOF). It is therefore imperative to develop advanced delivery methods for SOF in order to address existing absor ption issue and maximize the efficacy. In this study, we developed microneedle-integrated SOF (MN-SOF) which were elongated with branches and coated capsules to form luminar capsule microneedles (LUCAMs). To facilitate the formulation of LUCAMs, analytical methods for SOF in ethanol, artificial intestinal fluid (AIF), and artificial gastric fluid (AGF) were developed using a UV-vis spectrophotometer and colorimetric techniques in liver tissue. These methods were validated by combi ning the samples with ammonium metavanadate reagent. The validation process was conducted in order to ensure the accuracy, precision, linearity, specificity, and sensitivity of the methods. These methods exhibited a correlation coefficient of 0.9999, with a coefficient of variation below 25%. The methods demonstrate high accuracy and precision, with relative standard deviation (RSD) values ranging from 0.67% to 9.42% across different medium. The limit of detection (LOD) and limit of quantification (LOQ) values of SOF on each calibration curve of ethanol, artificial gastric fluid (AGF), artificial intestinal fluid (AIF), and rabbit liver tissue are 0.54μg/mL and 1.65μg/mL; 0.54μg/mL and 1.64μg/mL; 0.39μg/mL and 1.21μg/mL; 0.27μg/mL and 0.83μg/mL. As a significant outcome, the analytical method was validated and demonstrated suitability for determining the amount of SOF in the LUCAMs formulation through in vitro solubility, ex vivo permeation profiles, and in vivo drug delivery studies.