Molecular Inclusion Complex of Curcumin–β-Cyclodextrin Nanoparticle to Enhance Curcumin Skin Permeability from Hydrophilic Matrix Gel

Curcumin (CUR) has various pharmacological effects, but its extensive first-pass metabolism and short elimination half-life limit its bioavailability. Therefore, transdermal application has become a potential alternative to delivery CUR. To increase CUR solubility for the development of a transparent homogenous gel and also enhance the permeation rate of CUR into the skin, β-cyclodextrin–curcumin nanoparticle complex (BCD–CUR-N) was developed. CUR encapsulation efficiency was increased by raising the percentage of CUR to BCD up to 20%. The mean particle size of the best CUR loading formula was 156 nm. All evaluation data using infrared spectroscopy, Raman spectroscopy, powder X-ray diffractometry, differential thermal analysis and scanning electron microscopy confirmed the successful formation of the inclusion complex. BCD–CUR-N increased the CUR dissolution rate of 10-fold (p < 0.01). In addition, the improvement of CUR permeability acrossed skin model tissue was observed in gel containing the BCD–CUR-N and was about 1.8-fold when compared with the free CUR gel (p < 0.01). Overall, CUR in the form of the BCD–CUR-N improved the solubility further on the penetration of CUR.