title: Effect of gamma irradiation on structural and biological properties of a PLGA-PEG-hydroxyapatite composite.
abstract: Gamma irradiation is able to affect various structural and biological properties of biomaterials In this study, a composite of Hap/PLGA-PEG and their ingredients were submitted to gamma irradiation doses of 25 and 50 KGy. Various properties such as molecular weight (GPC), thermal behavior (DSC), wettability (contact angle), cell viability (MTT assay), and alkaline phosphatase activity were studied for the composites and each of their ingredients. The results showed a decrease in molecular weight of copolymer with no change in the glass transition and melting temperatures after gamma irradiation. In general gamma irradiation can increase the activation energy ΔH of the composites and their ingredients. While gamma irradiation had no effect on the wettability of copolymer samples, there was a significant decrease in contact angle of hydroxyapatite and composites with increase in gamma irradiation dose. This study showed an increase in biocompatibility of hydroxyapatite with gamma irradiation with no significant effect on cell viability in copolymer and composite samples. In spite of the fact that no change occurred in alkaline phosphatase activity of composite samples, results indicated a decrease in alkaline phosphatase activity in irradiated hydroxyapatites. These effects on the properties of PLGA-PEG-hydroxyapatite can enhance the composite application as a biomaterial.
authors.affiliation: Department of Dental Biomaterials, School of Dentistry, Tehran University of Medical Sciences, End of North Kargar Street, Tehran, Iran.
authors.forename: Sima
authors.initials: S
authors.lastname: Shahabi
authors.affiliation: Department of Resin and Additives, Institute for Color Science and Technology, 55 Vafamanesh Street, HosseinabadSquare, P.O. Box 16765-654, Tehran, Iran.
authors.forename: Farhood
authors.initials: F
authors.lastname: Najafi
authors.affiliation: Laser Research Center of Dentistry, School of Dentistry, Tehran University of Medical Sciences, End of North Kargar Street, Tehran, Iran.
authors.forename: Abbas
authors.initials: A
authors.lastname: Majdabadi
authors.affiliation: Department of Dental Biomaterials, School of Dentistry, Tehran University of Medical Sciences, End of North Kargar Street, Tehran, Iran.
authors.forename: Tabassom
authors.initials: T
authors.lastname: Hooshmand
authors.affiliation: New Technologies Research Center (NTRC), Amirkabir University of Technology, 424 Hafez Avenue, Tehran, Iran.
authors.forename: Masoumeh
authors.initials: M
authors.lastname: Haghbin Nazarpak
authors.affiliation: Iranian Center for Medical Laser Research, ACECR Tehran Medical Sciences Branch, Tehran, Iran.
authors.forename: Batool
authors.initials: B
authors.lastname: Karimi
authors.affiliation: Department of Dental Biomaterials, School of Dentistry, Tehran University of Medical Sciences, End of North Kargar Street, Tehran, Iran.
authors.forename: Seyyed Mostafa
authors.identifier: 0000-0001-8737-8927
authors.initials: SM
authors.lastname: Fatemi
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D002152:Calorimetry, Differential Scanning; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002850:Chromatography, Gel; D017886:Durapatite / Q000737:chemistry* / Q000494:pharmacology / Q000528:radiation effects*; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects; D005720:Gamma Rays; D005898:Glass / Q000737:chemistry; D019344:Lactic Acid / Q000737:chemistry* / Q000494:pharmacology / Q000528:radiation effects*; D051379:Mice; D008855:Microscopy, Electron, Scanning; D008970:Molecular Weight; D011092:Polyethylene Glycols / Q000737:chemistry* / Q000494:pharmacology / Q000528:radiation effects*; D011100:Polyglycolic Acid / Q000737:chemistry* / Q000494:pharmacology / Q000528:radiation effects*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D012984:Software; D044366:Transition Temperature; D017155:Wettability; D014961:X-Ray Diffraction
chemical_list: D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D011092:Polyethylene Glycols; D017886:Durapatite; D000469:Alkaline Phosphatase