Two-step nanoprecipitation for  the production of protein-loaded PLGA nanospheres

Publication date: 2012 Source:Results in Pharma Sciences, Volume 2 Author(s): Moraima Morales-Cruz, Giselle M. Flores-Fernández, Myreisa Morales-Cruz, Elsie A. Orellano, José A. Rodriguez-Martinez, Mercedes Ruiz, Kai Griebenow One of the first methods to encapsulate drugs within polymer nanospheres was developed by Fessi and coworkers in 1989 and consisted of one-step nanoprecipitation based on solvent displacement. However, proteins are poorly encapsulated within polymer nanoparticles using this method because of their limited solubility in organic solvents. To overcome this limitation, we developed a two-step nanoprecipitation method and encapsulated various proteins with high efficiency into poly(lactic-co-glycolic)acid (PLGA) nanospheres (NP). In this method, a protein nanoprecipitation step is used first followed by a second polymer nanoprecipitation step. Two model enzymes, lysozyme and α-chymotrypsin, were used for the optimization of the method. We obtained encapsulation efficiencies of >70%, an amount of buffer-insoluble protein aggregates of typically <2%, and a high residual activity of typically >90%. The optimum conditions identified for lysozyme were used to successfully encapsulate cytochrome c(Cyt-c), an apoptosis-initiating basic protein of similar size, to verify reproducibility of the encapsulation procedure. The size of the Cyt-c loaded-PLGA nanospheres was around 300–400nm indicating the potential of the deliver...
Source: Results in Pharma Sciences - Category: Drugs & Pharmacology Source Type: research