title: Influence of ultrasonic processing on the macromolecular properties of poly (D,L-lactide-co-glycolide) alone and in its biocomposite with hydroxyapatite.
abstract: In this work poly(D,L-lactide-co-glycolide) (PLGA) and a poly(d,l-lactide-co-glycolide)/hydroxyapatite (PLGA/HAp) composite processed in an ultrasonic field at higher (25 degrees C) and lower (8 degrees C) temperatures were studied with respect to the molecular properties of the obtained materials. The processing of the PLGA and the PLGA/HAp composite in an ultrasonic field resulted in a change of molar mass averages of the polymer/polymeric part of these materials, while an amorphous structure and a 50:50 lactide-to-glycolide co-monomer ratio were preserved without the formation of crystalline oligomers. However, mobility of polymeric chains obtained after ultrasonic processing was lower indicating ordering the structure of polymeric chains as a result of processing. Additionally, it was observed that the mobility of the PLGA macromolecules was lower within the composite in comparison with the mobility of the chains within the PLGA alone in the case when both were obtained after ultrasonic processing. This was a consequence of the structure formation through the interactions between the PLGA and the HAp. Based on these results different degradation rate of PLGA in composite can be expected, which is important in the application of this material for the controlled drug delivery of medicaments.
authors.affiliation: Institute of Technical Sciences of the Serbian Academy of Sciences and Arts, Knez Mihailova 35/IV, 11000 Belgrade, Serbia. marija.vukomanovic@itn.sanu.ac.rs
authors.forename: Marija
authors.initials: M
authors.lastname: Vukomanović
authors.forename: Miodrag
authors.initials: M
authors.lastname: Mitrić
authors.forename: Sreco D
authors.initials: SD
authors.lastname: Skapin
authors.forename: Ema
authors.initials: E
authors.lastname: Zagar
authors.forename: Janez
authors.initials: J
authors.lastname: Plavec
authors.forename: Nenad
authors.initials: N
authors.lastname: Ignjatović
authors.forename: Dragan
authors.initials: D
authors.lastname: Uskoković
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry* / Q000528:radiation effects*; D017886:Durapatite / Q000737:chemistry* / Q000528:radiation effects*; D019344:Lactic Acid / Q000737:chemistry* / Q000528:radiation effects*; D046911:Macromolecular Substances / Q000737:chemistry / Q000528:radiation effects; D011100:Polyglycolic Acid / Q000737:chemistry* / Q000528:radiation effects*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D013010:Sonication
chemical_list: D001672:Biocompatible Materials; D046911:Macromolecular Substances; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D017886:Durapatite