Transdermal delivery system of nanostructured lipid carriers loaded with Celastrol and Indomethacin: optimization, characterization and efficacy evaluation for rheumatoid arthritis

AbstractCo-encapsulation of drugs provides a convenient means for treating different symptoms of a disease. Celastrol (Cel) shows potent anti-arthritic activity and Indomethacin (Indo) is effective in relieving inflammatory pain. Nanostructured lipid carriers loaded with Celastrol and Indomethacin (Cel-Indo-NLCs) were prepared by emulsification evaporation–solidification method, optimized by the Box–Behnken design and characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and powder X-ray diffraction analysis (PXRD). Visualization of transdermal translocation of Cel-Indo-NLCs was achieved by confocal laser scanning microscope (CLSM). Further, Cel-Indo-NLCs were incorporated into Carbopol 940 for transdermal delivery. The in vitro studies were evaluated by using the Franz diffusion cells. Cel-Indo-NLCs depicted small particle size (26.92 ± 0.62 nm) and PDI (0.201 ± 0.01), high entrapment efficiency (96.56 ± 1.41%) and drug load (3.65 ± 0.05%). Moreover, Cel-Indo-NLCs sho...