LAUSR

Abstract In this study, hydrogels containing ibuprofen-loaded solid lipid nanoparticles (IBU-loaded SLNs) were developed to enhance the skin penetration of ibuprofen and for the local treatment of inflammation in experimental rats. IBU-loaded SLNs were prepared using cetostearyl alcohol as a solid lipid material in the oil phase, Tween 80 as an emulsifier in the aqueous phase, and NaOH as a solubilization enhancer. The optimized IBU-loaded SLN dispersions were also characterized according to the average particle size (from 98 ± 3 nm to 101 ± 1 nm), polydispersity index (from 0.119 ± 0.004 to 0.181 ± 0.019), zeta potential (from −2.66 ± 0.14 mV to −3.46 ± 0.75 mV), and encapsulation efficiency (from 56.88% to 58.89%). The gelling agent xanthan gum showed a crucial role in forming a homogeneous and stable network for incorporating and maintaining IBU-loaded SLNs on the skin, as examined via scanning electron microscopy and rheological properties analysis. Subsequently, IBU-loaded SLN-based hydrogels with an IBU:cetostearyl alcohol ratio of 1:1 exhibited the highest enhancement of in vitro permeation through the skin (a flux of 529.67 μg/cm2/h) and efficacy in treating inflammation in rats, compared with other prepared hydrogels and the commercial product Nurofen® 5% Gel.