title: Preparation and characterization of trace elements-multidoped injectable biomimetic materials for minimally invasive treatment of osteoporotic bone trauma.
abstract: It has always been a clinical challenge to use the proper implants or biomaterials to restore function to traumatized bone defects in patients with osteoporosis. In this study, we prepared the alginate-chitosan/trace elements-multidoped octacalcium phosphate-bioglass (AT-CS/teOCP-BG) hydrogel composite as an injectable biomaterial and evaluated its physicochemical properties and biological performance. Trace amount of silicon, strontium, and zinc was first doped into the structure of OCP porous microspheres via a wet chemical reaction. The AT-CS complex was mechanically mixed with teOCP and then neutralized by the ionic products of bioglass 58S particles dissolution. Formulations of this novel composite presented in wet state have teOCP-BG contents ranging from 7.8 to 25.4% and AT-CS content of below 3.2%. The composite retained gel in culture medium at 37°C, and the ratio of storage modulus and loss modulus (G'/G″) exhibited a marked increase with decreasing the amount of BG, signifying a pH-dependent enhancement of rheological properties and gel stability. After injection into rat femoral bone marrow cavity with minimal tissue invasion, new bone ingrowth was observed from radiologic images in the ovariectomized (OVXed) rats, which was significantly greater than that found in sham-operated animals within 8 weeks postoperatively. The fast bone regeneration phenomenon was observed in the OVXed rats by radiographic and microcomputerized tomography examination and histological analysis. These findings suggest that the AT-CS/teOCP-BG system might be used as an injectable biomaterial for minimally invasive treatment of osteoporosis-related (micro-)trauma.
authors.affiliation: Zhejiang-California International NanoSystems Institute, Zhejiang University, Hangzhou, China.
authors.forename: Xianyan
authors.initials: X
authors.lastname: Yang
authors.forename: Yilai
authors.initials: Y
authors.lastname: Gan
authors.forename: Xin
authors.initials: X
authors.lastname: Gao
authors.forename: Li
authors.initials: L
authors.lastname: Zhao
authors.forename: Changyou
authors.initials: C
authors.lastname: Gao
authors.forename: Xinli
authors.initials: X
authors.lastname: Zhang
authors.forename: Yanbo
authors.initials: Y
authors.lastname: Feng
authors.forename: Kang
authors.initials: K
authors.lastname: Ting
authors.forename: Zhongru
authors.initials: Z
authors.lastname: Gou
mesh_terms: D000818:Animals; D040761:Biomimetic Materials / Q000138:chemical synthesis* / Q000494:pharmacology / Q000627:therapeutic use*; D015519:Bone Density / Q000187:drug effects; D002130:Calcium Phosphates / Q000494:pharmacology; D002516:Ceramics / Q000494:pharmacology; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology*; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000737:chemistry; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D007267:Injections; D007477:Ions; D008422:Materials Testing / Q000379:methods*; D008855:Microscopy, Electron, Scanning; D010024:Osteoporosis / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012212:Rheology / Q000187:drug effects; D014131:Trace Elements / Q000494:pharmacology / Q000627:therapeutic use*; D014867:Water / Q000737:chemistry; D055114:X-Ray Microtomography
chemical_list: C022107:Bioglass; D002130:Calcium Phosphates; D007477:Ions; D014131:Trace Elements; D014867:Water; C022045:octacalcium phosphate; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate