Albumin coupled lipid nanoemulsions of diclofenac for targeted delivery to inflammation.

Diclofenac lipid nanoemulsions (DLNEs) were prepared with different compositions. Based on size, PDI, zeta potential, and in vitro drug release, the optimized DLNEs (DLNE-4 and DLNE-7) were developed and evaluated for drug content, entrapment efficiencies, and stability in comparison to the control formulation (DLNE-1). The albumin was coupled to DLNE-7 globules (DLNE-8) by water soluble carbodiimide (EDC) method, purified, and quantified by modified Bradford method. The pharmacokinetic study was conducted in inflammation (granuloma air pouch model) induced rats. The maximum peak concentration of DLNE-8 was almost fourfold to fivefold in comparison to drug solution in granuloma air pouch fluid (GAPF). The therapeutic availability (TA) of DLNE-8 was 2.89, 2.34, and 1.66 times that of drug solution, DLNE-4 and DLNE-7, respectively. The GAPF/serum ratio of diclofenac from DLNE-8 was above one at all time points indicating the targeting potential of albumin ligated LNEs to inflammatory sites. FROM THE CLINICAL EDITOR: This study demonstrates targeted delivery of diclofenac to an inflammatory environment using the granuloma air pouch model and diclofenac nanoemulsions with different compositions.

Brain specific delivery of pegylated indinavir submicron lipid emulsions.

The aim of this study was to develop stable parenteral pegylated indinavir submicron lipid emulsions (SLEs) for improving brain specific delivery. The O/W SLEs were prepared by homogenization and ultra sonication process. The sizes of oil globules varied from 241.5 to 296.4nm and zeta potential from -26.6 to -42.4mV. During in vitro drug release studies the cumulative amount of drug released within 12h from SLE-5, DSP2-3 and DPP5-3 was 71.8±0.76, 66.09±1.45 and 68.33±1.29, respectively. The total drug content and entrapment efficiencies were determined. The optimized formulations were stable for the effect of centrifugal stress, thermal stress, dilution stress and storage. In vivo pharmacokinetic and tissue distribution studies were performed in Swiss albino mice, the therapeutic availability (TA) of DSP2-3 was 3.59 times and 2.36 times in comparison to drug solution and SLE-5 respectively, where as DPP5-3 showed TA 2.8 and 1.84 times the drug solution and SLE-5, respectively. The brain to serum ratio of indinavir from DSP2-3 and DPP5-3 varied between 0.4 and 0.7 at all time points indicated the preferential accumulation of drug in brain. In conclusion, pegylated SLEs improved brain specific delivery of indinavir and will be useful in treating chronic HIV infection.