Development of a liposomal nanodelivery system for nevirapine

Abstract

BackgroundThe treatment of AIDS remains a serious challenge owing to high genetic variation of Human Immunodeficiency Virus type 1 (HIV-1). The use of different antiretroviral drugs (ARV) is significantly limited by severe side-effects that further compromise the quality of life of the AIDS patient. In the present study, we have evaluated a liposome system for the delivery of nevirapine, a hydrophobic non-nucleoside reverse transcriptase inhibitor. Liposomes were prepared from egg phospholipids using thin film hydration. The parameters of the process were optimized to obtain spherical liposomes below 200 nm with a narrow polydispersity. The encapsulation efficiency of the liposomes was optimized at different ratios of egg phospholipid to cholesterol as well as drug to total lipid. The data demonstrate that encapsulation efficiency of 78.14% and 76.25% were obtained at egg phospholipid to cholesterol ratio of 9:1 and drug to lipid ratio of 1:5, respectively. We further observed that the size of the liposomes and the encapsulation efficiency of the drug increased concomitantly with the increasing ratio of drug and lipid and that maximum stability was observed at the physiological pH. Thermal analysis of the drug encapsulated liposomes indicated the formation of a homogenous drug-lipid system. The magnitude of drug release from the liposomes was examined under different experimental conditions including in phosphate buffered saline (PBS), Dulbecco's Modified Eagle's Medium (DMEM) supplemented with 10% fetal bovine serum or in the presence of an external stimulus such as low frequency ultrasound. Within the first 20 minutes 40, 60 and 100% of the drug was released when placed in PBS, DMEM or when ultrasound was applied, respectively. We propose that nevirapine-loaded liposomal formulations reported here could improve targeted delivery of the anti-retroviral drugs to select compartments and cells and alleviate systemic toxic side effects as a consequence.

Tretinoin-loaded liposomal formulations: from lab to comparative clinical study in acne patients

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EpCAM-targeted liposomal si-RNA delivery for treatment of epithelial cancer

“…In contrast, the levels of plasma protein adsorbed on the liposomal carriers over the same period of time were found to be significantly higher. This may be due to the presence of a large number of proteins with varying sizes and isoelectric points in the plasma, which can contribute to an accelerated adsorption of proteins (Chono et al, 2008;Ramana et al, 2010).…”

Effective-Loading of Platinum–Chloroquine into PEGylated Neutral and Cationic Liposomes as a Drug Delivery System for Resistant Malaria Parasites

“…The absorbance was converted into drug concentration using a standard curve. The EE was calculated using the previously reported equation 26) : EE Drug encapsulated / Total drug) 100% =( × For PtCQ-loaded liposomes prepared using the remoteloading method, the samples were cooled and applied onto a gel filtration column (CL-4B, Sigma-Aldrich) equilibrated with HBS to remove unencapsulated PtCQ. The liposome fraction of the eluate was collected, the concentration of lipid was determined again, and the concentration of the encapsulated drug was measured as described above.…”