Transdermal Delivery of Curcumin-Loaded Solid Lipid Nanoparticles as Microneedle Patch: an In Vitro and In Vivo Study.

Curcumin is well known for its neuroprotective effect, and also able to alleviate Parkinsonian features. Clinical application of curcumin is limited due to its low bioavailability. Hence, we hypothesized that the microneedles (MN) containing drug-loaded solid lipid nanoparticles (SLNs) may be able to improve its bioavailability and efficacy. The SLNs were prepared with microemulsion technique using glyceryl monostearate as a lipid and tween 80 as a stabilizer. The particle size, polydispersity index, zeta potential, and entrapment efficiency of prepared SLNs were determined. The optimized formulation was incorporated into microneedle arrays using micromolding technique and fabricated microneedle patch were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, optical microscopy, ex vivo permeation studies, histology studies, and fluorescent microscopy. The fabricated microneedle patch was also evaluated for neuroprotective activity and skin irritation potential. Fourier transform infrared spectroscopy studies of SLNs and microneedles confirmed the chemical compatibility of excipients with curcumin. The developed microneedles were also found to be non-irritant with decreased degree of bradykinesia, high motor coordination, and balance ability. The study provided a theoretical basis for the use of novel microneedle containing curcumin-loaded solid lipid nanoparticles as a useful tool for the treatment of Parkinson's disease.