title: Development and characterization of GRGDSPC-modified poly(lactide-co-glycolide acid) porous microspheres incorporated with protein-loaded chitosan microspheres for bone tissue engineering.
abstract: Scaffolds that can achieve cell adhesion and controlled release of protein drugs are very promising in bone tissue engineering. Due to their biocompatibility and injectablity, poly(lactide-co-glycolide acid) (PLGA) porous microspheres (PLGA-pMS) present potential scaffolds in bone tissue engineering. However, their application is hampered by the burst release of protein drugs and hydrophobicity that leads to poor cell adhesion. To overcome these drawbacks, we developed novel PLGA-pMS by incorporating bovine serum albumin (BSA) loaded chitosan microspheres (CS-MS) in Gly-Arg-Gly-Asp-Ser-Pro-Cys (GRGDSPC) modified PLGA-pMS (CS-MS/PLGA-pMS). GRGDSPC was used to enhance the hydrophilicity and cell affinity of the porous microspheres. Results showed that PLGA-pMS had a size of 446.77±19.46μm, with an average surface pore size of 21.56±3.02μm, whereas CS-MS had a size of 15.98±0.96μm and 16.35±0.38μm (5% and 10% TPP-prepared CS-MS, respectively). A scanning electron microscope (SEM) and a confocal laser scanning microscope (CLSM) revealed that CS-MS were partly embedded in the PLGA matrices and the integrity of CS-MS was retained. Thermogravimetry analyzer (TGA) also demonstrated that CS-MS were incorporated into PLGA-pMS. The CS-MS/PLGA-pMS had a size of 454.02±16.09μm, with a BSA encapsulation efficiency of 53.19±1.67% and 62.16±3.44% (5% and 10% TPP-prepared CS-MS, respectively). CS-MS/PLGA-pMS exhibited a sustained FITC-BSA release for 28 days. Modification of GRGDSPC significantly improved adhesion of MG-63 cells on the porous microspheres. In conclusion, CS-MS/PLGA-pMS may act as potential bifunctional scaffolds for bone tissue engineering.
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Second Military Medical University, Shanghai 200433, PR China.
authors: Chun
authors: C
authors: Tao
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Second Military Medical University, Shanghai 200433, PR China.
authors: Jingbin
authors: J
authors: Huang
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Second Military Medical University, Shanghai 200433, PR China.
authors: Ying
authors: Y
authors: Lu
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Second Military Medical University, Shanghai 200433, PR China.
authors: Hao
authors: H
authors: Zou
authors: Department of Medical Imaging, Changhai Hospital, Second Military Medical University, Shanghai 200433, PR China.
authors: Xinyi
authors: X
authors: He
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Second Military Medical University, Shanghai 200433, PR China. Electronic address: tulipcy51@sina.com.
authors: Yan
authors: Y
authors: Chen
authors: Department of Pharmaceutical Sciences, School of Pharmacy, Second Military Medical University, Shanghai 200433, PR China. Electronic address: yqzhong68@163.com.
authors: Yanqiang
authors: Y
authors: Zhong
mesh_terms: D001846:Bone Development; D002448:Cell Adhesion; D048271:Chitosan / Q000737:chemistry*; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008863:Microspheres; D009842:Oligopeptides / Q000737:chemistry*; D010006:Osteoblasts / Q000166:cytology; D011100:Polyglycolic Acid / Q000737:chemistry*; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D016062:Porosity; D011506:Proteins / Q000737:chemistry*; D013818:Thermogravimetry; D023822:Tissue Engineering
chemical_list: C112077:Gly-Arg-Gly-Asp-Ser-Pro-Cys; D009842:Oligopeptides; D011506:Proteins; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid; D048271:Chitosan
keywords: Bone tissue engineering; Chitosan; Microspheres; Poly(lactide-co-glycolide acid); RGD peptide