Development and Optimization of Nanolipid-Based Formulation of Diclofenac Sodium: In Vitro Characterization and Preclinical Evaluation.

In the present research study, we formulate bilosomes (BMs) of diclofenac (DC) for oral delivery for enhancement of therapeutic efficacy (anti-inflammatory disease). The BMS were prepared by thin film hydration method and optimized by Box-Behnken design (BBD) using cholesterol (A), lipid (B), surfactant (C), and bile salt (D) as formulation factors. Their effects were evaluated on vesicle size (Y 1 ) and entrapment efficacy (Y 2 ). The optimized DC-BMs-opt showed a vesicle size of 270.21 ± 3.76 nm, PDI of 0.265 ± 0.03, and entrapment efficiency of 79.01 ± 2.54%. DSC study result revealed that DC-BMs-opt exhibited complete entrapment of DC in BM matrix. It also depicted significant enhancement ( p < 0.05) in release (91.82 ± 4.65%) as compared to pure DC (36.32 ± 4.23%) and DC-liposomes (74.54 ± 4.76%). A higher apparent permeability coefficient (2.08 × 10 -3 cm/s) was also achieved compared to pure DC (6.6 × 10 -4 cm/s) and DC-liposomes (1.33 × 10 -3 cm/s). A 5.21-fold and 1.43-fold enhancement in relative bioavailability was found relative to pure DC and DC liposomes (DC-LP). The anti-inflammatory activity result showed a significant ( p < 0.05) reduction of paw edema swelling compared to pure DC and DC-LP. Our findings revealed that encapsulation of DC in BMs matrix is a good alternative for improvement of therapeutic efficacy.