title: Design and characterisation of new nanoparticulate polymer blends for drug delivery.
abstract: The aim of the present work was the design of novel nanoparticle compositions based on poly(lactic acid/glycolic acid) (PLGA): poloxamer and PLGA: poloxamine blend matrices. For this purpose, we have applied a modified solvent diffusion technique that allows the preparation of the nanoparticles without the use of high energy sources. Nanoparticles have been prepared with different PLGA: poloxamer and PLGA: poloxamine ratios using PEO-derivatives with different molecular weights (Mw) and hydrophilia-lipophilia balance (HLB) values. Our results show that the physicochemical characteristics of the nanoparticles, such as size and zeta potential, are influenced by the type of PEO-derivative associated to the PLGA matrix. The 1H-NMR analysis of the different nanoparticle compositions showed that the extent of incorporation of the PEO-derivative depends strongly on its HLB and also on the nanoparticles preparation conditions. The capacity of these nanoparticles as drug delivery devices was evaluated using bovine insulin as a model drug. The insulin-encapsulation efficiency was shown to be dependent on the composition of the nanoparticles, those containing hydrophilic PEO-derivatives being the most effective in entrapping the drug molecules. The formation of the blend system displayed positive effects on the release characteristics of the nanoparticles. Nanoparticles exhibited a reduced initial burst and a nearly linear, constant release rate over a time period of two weeks.
authors.affiliation: Department of Pharmacy and Pharmaceutical Technology, School of Pharmacy, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain.
authors.forename: N
authors.initials: N
authors.lastname: Csaba
authors.forename: L
authors.initials: L
authors.lastname: González
authors.forename: A
authors.initials: A
authors.lastname: Sánchez
authors.forename: M J
authors.initials: MJ
authors.lastname: Alonso
mesh_terms: D000818:Animals; D002417:Cattle; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004337:Drug Carriers / Q000138:chemical synthesis* / Q000737:chemistry*; D016503:Drug Delivery Systems; D015195:Drug Design; D066298:In Vitro Techniques; D007328:Insulin / Q000008:administration & dosage; D019344:Lactic Acid / Q000737:chemistry; D008422:Materials Testing; D008854:Microscopy, Electron; D049329:Nanostructures / Q000737:chemistry; D010316:Particle Size; D020442:Poloxamer / Q000737:chemistry; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D004337:Drug Carriers; D007328:Insulin; D011108:Polymers; D020442:Poloxamer; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid