Green Preparation of Naproxen‐Loaded Solid Lipid Nanoparticles Based on Glyceryl Behenate to Improve Transdermal Absorption

ABSTRACT Naproxen is one of the non‐steroidal anti‐inflammatory drugs which show some side effects via oral administration. Percutaneous delivery of this drug can reduce these adverse effects. The bioavailability of naproxen could be promoted by several methods including administration of naproxen‐loaded nanoparticles. In this research solid lipid nanoparticles (SLN) based on glyceryl behenate were developed as drug carriers and after characterization, the percutaneous absorption of optimum nanoparticles was compared with plain topical naproxen preparation. Naproxen‐loaded SLNs were prepared by emulsification followed by ultrasonication method. Several nanoparticles were formulated with different amounts of glyceryl behenate as lipid phase and some ratios of Tween 60 and Span 80 as emulsifiers. Selected formulation showed a mean particle size of 259.6 ± 10.2 nm, a polydispersity index (PDI) of 0.39 ± 0.04, a zeta potential of −10.7 ± 0.6 mV and a drug loading of 63.9% ± 5.6%. These data were confirmed by SEM (Scanning Electron Microscope) analysis. DSC (Differential Scanning Calorimetry) and FTIR (Fourier Transform Infrared) spectroscopy proved the drug loading and showed no chemical interaction between formulation ingredients. The percutaneous absorption study via rat skin showed significant drug absorption of naproxen SLN after 24 h via rat skin which was 261.22 ± 86.25 μg/cm 2 of rat skin, in comparison with simple naproxen solution, 41.66 ± 10.88 μg/cm 2 of rat skin ( p  < 0.0001). This observation was made regarding the drug retained in the skin after 24 h ( p  < 0.0001). These results indicated SLN prepared based on glyceryl behenate can improve naproxen permeation via skin and can be used as a novel system for dermal drug delivery.