Enhanced Transdermal Co-Delivery of Diacerein and Aceclofenac for Osteoarthritis Using a Novel D-optimal Design-Based Nanoemulgel
摘要
This research aimed to develop and optimize an innovative nanoemulsion (NE) and nanoemulgel (NEG) formulation for enhanced transdermal co-delivery of diacerein (DCN) and aceclofenac (ACE) using a D-optimal mixture design approach. A DCN-and ACE-loaded NE was prepared by a spontaneous emulsification using an oil mix (Triacetin: Capmul MCM C8, 2:1 w/w) and surfactant/co-surfactant mixture (Kolliphor-EL: Transcutol P, 1:1 w/w). The optimized NE was then converted into an NEG using hydroxypropyl methylcellulose. The optimized NE was found to be thermodynamically stable, featuring spherical, nanoscale globules as confirmed by FE-SEM and TEM imaging. An in vitro release using dialysis membrane and an ex vivo permeation study using Wistar rat skin demonstrated significantly higher drug release, flux, and skin deposition for the optimized NEG than plain gels. The NEG showed good stability, with acute skin toxicity and histopathology studies confirming it to be non-irritating and non-toxic. An in vivo pharmacokinetic study in Wistar rats revealed markedly higher systemic exposure of rhein (the active metabolite of DCN), ACE, and diclofenac (the active metabolite of ACE) from the optimized NEG compared to a marketed oral tablet, with statistically significant enhancement in AUC (p < 0.05). The enhanced exposure is attributed to bypassing first-pass metabolism and improved transdermal flux. This nanoemulgel platform offers a promising technique for the transdermal delivery of drugs with poor oral and transdermal bioavailability and significant oral side effects by improving patient compliance through reduced dosing frequency and enhancing therapeutic effectiveness.