Development of DH-I-180-3 loaded lipid nanoparticle for photodynamic therapy.

Photodynamic therapy (PDT) is a promising noninvasive treatment modality for cancer. Photosensitizer and specific wave length of light are the key component of PDT. DH-I-180-3, a second generation photosensitizer, was incorporated into lipid nanoparticle for simultaneous fluorescent imaging and targeting therapy. Solid lipid nanoparticle (SLN) and nanostructured lipid carriers (NLC) based on poloxamer 188 as surfactant and lecithin as co-surfactant were prepared using solvent evaporation and hot homogenization technique. Stearic acid and Capmul(®) MCM C8 were utilized as solid lipid and liquid lipid, respectively. The particle size of SLN and NLCs was around 200 nm and decreased when a part of stearic acid was replaced with Capmul(®) MCM C8. Drug loading efficacy was significantly enhanced when the percentage amount of liquid lipid increased. All the polydispersity indices of the SLN/NLCs were below 0.3, and displayed a narrow particle size distribution. Zeta potentials of all the lipid nanoparticles were below -30 mV, maintaining sufficient repulsive force and achieving enhanced physical stability. No significant change in the particle size and polydispersity index was observed from lyophilized SLN/NLCs. When the photocytotoxic effects of the formulations were evaluated in MCF-7 cells, GI 50 of SLN was less than half of DH-I-180-3 solution, and NLCs containing either 5 or 15%w/w of Capmul(®) MCM C8 exerted higher cytotoxicity than SLN. The fluorescence microscope images displayed enhanced cellular accumulation of DH-I-180-3 loaded in SLN and NLCs, which was closely correlated with the photocytotoxicity results. It was concluded that the incorporation of DH-I-180-3 into the nanoparticles enhanced their targeting efficacy and improved photocytotoxicity.

Development of drug-in-adhesive patch formulations for transdermal delivery of fluoxetine: In vitro and in vivo evaluations.

The aim of this study was to develop drug-in adhesive (DIA) patch formulations for the transdermal delivery of fluoxetine (FX). The DIA patch formulations containing FX were prepared and optimized with various pressure sensitive adhesives, drug contents and enhancers. Among the various formulations, DuroTak 87-502B-based patch formulation containing 20% (w/w) FX with no enhancer was selected for in vivo pharmacokinetic study based on in vitro permeation studies using hairless mouse, rat and human cadaver skins. The Cmax of FX after the transdermal administration of the optimized patch formulation in rats was 52.38 ng/ml, and plasma concentration of FX was maintained for 36 h. Moreover, the predicted human Css (55.79 ng/ml) and Cmax (27.35 ng/ml) were in good agreement with the reported plasma levels (15-55 ng/ml) of oral FX in clinical applications. These results suggest that the optimized patch formulation could be further developed for clinical applications, providing the therapeutic plasma level of FX over an extended period. To the best of our knowledge, our results are the first reported in vitro and in vivo data on the preparation and optimization of FX-loaded DIA patch, showing its feasibility as an effective transdermal delivery system for FX.