Accelerated blood clearance of pegylated liposomal topotecan: influence of polyethylene glycol grafting density and animal species.

Upon repeated administration, empty pegylated liposomes lose long-circulating characteristics, referred to as accelerated blood clearance (ABC) phenomenon. However, pegylated liposomal cytotoxic drug formulations could not elicit the phenomenon. In the study, it was found that repeated injection of pegylated liposomal topotecan could induce ABC phenomenon in Wistar rats, beagle dogs, and mice, which might be associated with the formation of empty liposomes in circulation because of the rapid drug release rate.

Sulfosalicylate mediates improved vinorelbine loading into LUVs and antineoplastic effects.

Liposomal vinorelbine formulation is desirable, as it might improve the therapeutic activity of vinorelbine. However, because of its lipophilic and membrane-permeable properties, vinorelbine is hard to be formulated into liposomes using conventional drug-loading technologies. To improve vinorelbine retention, ammonium salts of several anionic agents were employed to prepare liposomal vinorelbine formulations.

Liposomes incorporating sodium deoxycholate for hexamethylmelamine (HMM) oral delivery: development, characterization, and in vivo evaluation.

Liposomes incorporating sodium deoxycholate (NaDC) were prepared by the method of reverse phase evaporation and used for drug delivery by the oral route. Hexamethylmelamine (HMM), an anti-tumor agent, was chosen as a model drug and encapsulated into liposomes incorporating NaDC (NaDC-Lip). Several properties of NaDC-Lip containing HMM (HMM NaDC-Lip), such as particle size, entrapment efficiency, pinacyanol chloride (PIN) spectral characteristics with various molar ratio of NaDC/PC, as well as the vesicle stability measurements with calcein were evaluated.

N-trimethyl chitosan-coated multivesicular liposomes for oxymatrine oral delivery.

Background: Multivesicular liposomes (MVLs), uncoated and coated with N-trimethyl chitosan (TMC), have been studied for their potential use for drug delivery by the oral route.

Method: Synthesized TMC was characterized by infrared spectroscopy, revealing the presence of trimethyl groups, and by proton nuclear magnetic resonance spectroscopy, allowing the calculation of the degree of substitution quaternization (70.2%).