*2.7. In Vitro Dissolution Studies*

FEN dissolution studies were performed to compare the dissolution kinetics of various SLH formulations, crystalline FEN and APO-fenofibrate. The studies were performed in 0.0125 M SLS solution, as FEN is a neutral drug and practically insoluble in aqueous media [32]. However, using SLS significantly enhances its solubility, and its use as a dissolution media has been evaluated for multiple FEN-containing formulations in order to achieve sink conditions [33–36]. Dissolution was performed using a Vankel USP II apparatus (Agilent Technologies, Santa Clara, CA, USA), 450 mL of media was maintained at 37 ◦C and rotating at 50 rpm. An equivalent of 10 mg of FEN of formulation was added to the dissolution vessel. Three-milliliter aliquots were removed at 1, 5, 10, 15, 30, 45, 60, and 90 min, replaced by fresh media, and filtered using 0.45 µm syringe filter prior to appropriate dilution with mobile phase and analysis with HPLC.
