Development and optimization of a novel drug free nanolipid vesicular system for treatment of osteoarthritis

The goal of this study is to improve the transdermal delivery of phosphatidylcholine (PC) via constructing a novel nanolipid vesicular system (NLVS) with high level of permeability through the stratum corneum (SC).

In our study, a novel drug free NLVS was developed. The system depends on PC boundary cartilage lubrication to relieve osteoarthritic pain without developing gastrointestinal problems associated with anti-inflammatory drug.

A full two-level (2³) factorial design is applied to optimize the quality of the prepared NLVS. The selected independent variables are the concentration of PC, the concentration of edge activator (EA), and EA type. The developed NLVS was evaluated for in-vitro, ex-vivo as well as in-vivo efficacy in rat animal model.

Based on the factorial design, the selected formulation variables significantly affect the tested responses. The prepared NLV formulations have a particle size (PS)in the range of 10.34 to 496.3 nm, polydispersity index (PdI) values less than one, and negative zeta potential (ZP) range of -1.42 to -32.01 mV. In-vitro and ex-vivo study results reveal that the designed NLVS is effective in sustaining PC release and enhancing its transdermal permeation over 24 h. The optimal permeation flux through ex-vivo study is 0.415 mg/cm²/h following zero-order kinetics. Moreover, in-vivo study of the optimized formulations demonstrated remarkable reduction in inflammatory mediators associated with osteoarthritis (OA).

The results indicate that the optimized drug free NLVS significantly augment transdermal delivery of PC and have a potential role in treatment of OA without the risk of systemic side effects.