Diclofenac Loaded Lipid Nanovesicles Prepared by Double Solvent Displacement for Skin Drug Delivery

Purpose Herein, we detail a promising strategy of nanovesicle preparation based on control of phospholipid self-assembly: the Double Solvent Displacement. A systematic study was conducted and diclofenac as drug model encapsulated. In vitro skin studies were carried out to identify better formulation for dermal/transdermal delivery. Methods This method consists in two solvent displacements. The first one, made in a free water environment, has allowed triggering a phospholipid pre-organization. The second one, based on the diffusion into an aqueous phase has led to liposome formation. Results Homogeneous liposomes were obtained with a size close to 100 nm and a negative zeta potential around -40 mV. After incorporation of acid diclofenac, we obtained nanoliposomes with a size between 101 +/- 45 and 133 +/- 66 nm, a zeta potential between 34 +/- 2 and 49 +/- 3 mV, and the encapsulation efficiency (EE%) was between 58 +/- 3 and 87 +/- 5%. In vitro permeation studies showed that formulation with higher EE% dispayed the higher transdermal passage (18,4% of the applied dose) especially targeting dermis and beyond. Conclusions Our results suggest that our diclofenac loaded lipid vesicles have significant potential as transdermal skin drug delivery system. Here, we produced cost effective lipid nanovesicles in a merely manner according to a process easily transposable to industrial scale.