Introduction: Solid Lipid Nanoparticles (SLNs) are emerging as effective carriers for enhancing drug delivery through controlled release and improved skin permeation. Lipids are the primary building blocks of lipid nanoparticles. First-generation solid lipid nanoparticles are prepared from solid lipids, which are biocompatible and acceptable to the human body. They are often derived from natural sources or synthesised through artificial processes. However, the use of natural, vegan, biocompatible lipids in SLN systems remains limited. This study aimed to explore soy wax, a vegan wax, as a novel lipid for the preparation of Solid lipid nanoparticles. Diclofenac Sodium (DFS) was used as a model drug. Methods: The empty and drug-loaded SLNs were prepared using high-shear homogenization followed by probe ultrasonication (20 kHz, 50% amplitude, pulse mode) and optimized for particle size, polydispersity index, zeta potential, drug loading, and encapsulation efficiency. The optimized formulation was formulated into a gel, and ex vivo skin permeation and in vivo anti-inflammatory activity were evaluated to assess the suitability of the soy wax-based SLN for encapsulating diclofenac sodium. Results: Based on the results, DFS-SLN 8 Batch was selected as the optimized formula, prepared with a 2% surfactant, a 1:2 drug-to-lipid ratio, and 4 minutes of sonication. The optimized soy wax-based SLNs exhibited a mean particle size of 106.3 ± 2.84 nm, a PDI of 0.239 ± 0.004, a surface charge of - 20.4 ± 6.19 mV, and a high encapsulation capacity of 87.40%. SLN-based gel displayed anomalous transport with an 81.34% drug release. Ex vivo skin permeation studies revealed 10.2 ± 0.65% drug permeation and 61.65 ± 1.50% cutaneous deposition. discussion: The in vivo anti-inflammatory study showed that the developed formulation had similar anti-inflammatory properties to those of the marketed product. Discussion: The present study demonstrates the successful development of soy wax–based SLNs as a vegan, biocompatible carrier system for topical delivery. The use of soy wax offers a promising alternative to conventional synthetic or animal-derived lipids, addressing the growing demand for sustainable and ethically acceptable pharmaceutical excipients. The formulations appeared as uniform, milkywhite dispersions upon cooling, indicating successful solidification of the lipid phase. Drug incorporation increased the particle size of empty soywax SLNs, attributed to drug entrapment within the lipid matrix. The optimized formulation exhibited nanoscale particle size, narrow size distribution, and adequate surface charge, indicating good physical stability and suitability for dermal application. The enhanced skin retention with limited permeation suggests effective localized drug delivery. The in vivo anti-inflammatory study showed that the developed formulation exhibited anti-inflammatory properties comparable to those of the marketed product. Conclusion: Soy wax–based Solid Lipid Nanoparticles (SLNs) were successfully developed and characterized. The optimized formulation exhibited a nanoscale particle size, an acceptable zeta potential, a uniform distribution, and sustained drug release in in vitro studies. In vivo anti-inflammatory studies showed that the developed formulation produced effects comparable to the marketed product. These results demonstrate the potential of soy wax as a promising, biocompatible carrier system for dermal delivery.
Chauhan et al. (Fri,) studied this question.