Topical Delivery of Puerarin Using Nanostructured Lipid Carrier Gel: Formulation, Characterization, and in Vitro Assessment

Objectives: Puerarin is one of the oldest and most significant edible crude herbs in traditional Oriental medicine and is used as a muscle relaxant, antipyretic, anti-inflammatory, and antidysentery, as well as in the treatment of cardiovascular diseases. Puerarin topical gel based on nanostructured lipid carriers (NLCs) was developed to treat inflammation. This research will focus on preparing and evaluating transdermal drug delivery system formulations using appropriate excipients. Furthermore, NLCs will be incorporated into a transdermal gel to achieve specific delivery. Finally, the performance and efficacy of the optimized transdermal gel containing puerarin-loaded NLC will be thoroughly evaluated. Methods: Propylene glycol served as a co-surfactant, Tween 20 as a surfactant, oleic acid as a liquid lipid, and stearic acid as a solid lipid made up of NLC. Particle size, differential scanning calorimetry, scanning electron microscopy, and Fourier transform infrared spectroscopy were used to characterize the NLCs using solvent emulsification procedures. Results: The NLC exhibited impressive entrapment efficiency across all formulations, ranging from 45.90% to 87.80%. Formulation F1 emerged as the optimal NLC composition with an average particle size of 61.70 nm and a polydispersity index of 0.345, indicating a homogeneous particle size distribution. The stability of Formulation F1 was further confirmed by its high-magnitude zeta potential of −13.0 mV. Subsequently, Formulation F6 of the puerarin-loaded NLC gel underwent successful gelling and was evaluated for various parameters which demonstrated optimum results, suggesting the suitability of the nanoparticulate dispersion for further development. Conclusion: The puerarin NLC gel exhibits potential for extended medication availability in skin tissues and may be applied more effectively to treat inflammatory diseases.