Physostigmine-loaded liposomes for extended prophylaxis against nerve agent poisoning

Publication date: Available online 30 October 2018Source: International Journal of PharmaceuticsAuthor(s): Ju-Hwan Park, Jae-Young Lee, Ki-Taek Kim, Hae-Eun Joe, Hyun-Jong Cho, Young-Kee Shin, Dae-Duk KimAbstractPre-administration of physostigmine can prevent poisoning against nerve agent exposure by reversibly binding to cholinesterase. However, its cholinesterase protection-based prophylactic effect can be eliminated rapidly due to short biological half-life. Liposomes are useful for encapsulating hydrophilic drugs like physostigmine, and can be used for sustained release after parenteral injection. Thus, physostigmine liposomes were prepared by the pH-gradient condition-based remote-loading method for subcutaneous injection. In addition, polyethylene glycol (PEG)-lipid was applied to further extend the release of physostigmine and its prophylactic action. In vitro release of physostigmine, pharmacokinetics and duration of prophylactic effect were then evaluated. Physostigmine was dissolved in distilled water and used as a solution group for comparison. The prepared liposomes showed spherical shape and their particle size was around 130 μm. Addition of PEG-lipid in liposomes significantly increased the entrapment efficiency of physostigmine. Both control and PEG liposomes exhibited sustained release pattern compared to the solution. Moreover, the release of PEG liposomes was relatively slower than that of the control liposomes. Pharmacokinetic study in rats revealed that p...
Source: International Journal of Pharmaceutics - Category: Drugs & Pharmacology Source Type: research