In situ gelation of PEG-PLGA-PEG hydrogels containing high loading of hydroxyapatite: in vitro and in vivo characteristics.
Thermosensitive hydrogels are renowned carriers that are used to deliver a variety of drugs with the aim of combating diseases. In this study, the injectability of thermosensitive hydrogels comprised of poly(ethylene glycol)-poly(lactic acid-co-glycolic acid)-poly(ethylene glycol) (PEG-PLGA-PEG, PELGE) and hydroxyapatite (HA) were examined for their ability to deliver bone morphological protein 2 (BMP-2). The physicochemical characteristics of PELGE, HA, and PELGE/HA hydrogel composites were investigated by (1)H NMR, GPC, FTIR, XRD, SEM, and TEM. The rheological properties, injectability, in vitro degradation, and in vivo biocompatibility were investigated. The hydrogel with a weight ratio of 4:6 of polymer to HA was found to be resistant to auto-catalyzed degradation of acidic monomers (LA, GA) for a period of 70 days owing to the presence of alkaline HA. Injectability was quantitatively determined by the ejected weight of the hydrogel composite at room temperature and was a close match to the weight amount predetermined by the syringe pump. The results not only revealed that the PELGE/HA hydrogel composite presented a minor tissue response in the subcutis of ICR mice at eight weeks, but they also indicated an acceptable tolerance of the hydrogel composite in animals. Thus, PELGE/HA hydrogel composite is expected to be a promising injectable orthopedic substitute because of its desirable thermosensitivity and injectability.
Department of Chemistry, Center for Nanotechnology and Center for Biomedical Technology at Chung-Yuan Christian University, Chung Li, Taiwan 32023, Republic of China.
Mei-Chun
MC
Lai
Kung-Chin
KC
Chang
Sheng-Chieh
SC
Hsu
Ming-Chieh
MC
Chou
Wei-I
WI
Hung
You-Rong
YR
Hsiao
Hung-Maan
HM
Lee
Ming-Fa
MF
Hsieh
Jui-Ming
JM
Yeh
D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D055396:Bone Morphogenetic Protein 2 / Q000737:chemistry*; D002454:Cell Differentiation; D017886:Durapatite / Q000737:chemistry*; D020100:Hydrogels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D051379:Mice; D008813:Mice, Inbred ICR; D010012:Osteogenesis; D044367:Phase Transition; D011092:Polyethylene Glycols / Q000737:chemistry*; D011098:Polyglactin 910 / Q000737:chemistry*; D013696:Temperature; D023822:Tissue Engineering
D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D020100:Hydrogels; C520330:polyethylene glycol-poly(lactic-co-glycolic acid)-polyethylene glycol; D011098:Polyglactin 910; D011092:Polyethylene Glycols; D017886:Durapatite