Biocompatible Magnesium Implant Double-Coated with Dexamethasone-Loaded Black Phosphorus and Poly(lactide-co-glycolide)

Abstract

Magnesium (Mg) and its alloys have presented a paradigm for biodegradability in the field of biomedical devices. However, biodegradation of Mg and its alloys cause the formation of hydrogen gas and basic molecules in the body. Here we developed a surface modification method for Mg implants by double-coating with osteogenic dexamethasone (Dex)-loaded black phosphorus (BP) and poly­(lactide-co-glycolide) (PLGA). According to electrochemical and biodegradation tests, the prepared Mg-Dex/BP/PLGA showed remarkably enhanced resistance against corrosion possibly by the neutralization of basic molecules from Mg implants with acidic molecules from BP and PLGA with increasing biodegradation. Scanning electron microscopy, cell proliferation tests, Alizarin Red staining, and alkaline phosphatase activity tests confirmed that MC3T3-E1 cells significantly proliferated and were differentiated on the Mg-Dex/BP/PLGA surface. Taken together, the facile surface modification of Mg implants could be effectively harnessed for protecting the Mg surface from corrosion and inducing the osseointegration of preosteoblasts onto the Mg implant.

In Vivo Study of Local and Systemic Responses to Clinical Use of Mg–1Ca Bioresorbable Orthopedic Implants

“…Gas bubble formation is believed to present a negative influence on wound healing. The theory behind this process is that gas bubbles might induce tissue dissection and thus cause a delayed wound closing [ 22 , 25 ]. However, in our study, none of the cases displayed delayed wound healing, with per secundam closing, up until euthanasia.…”

Progress in bioactive surface coatings on biodegradable Mg alloys: A critical review towards clinical translation

“…12 (b, c) is characterized by its clear spatial defect-free appearance. Despite efficient corrosion inhibition, a few generic limitations like high susceptibility towards hydrolysis, entrapment of H 2 during in-vitro immersion, and poor adhesion towards Mg substrate hampers its usage for orthopedic implant application [ 300 ]. Recent attempts have overcome these problems, but the outcomes still do not fulfill the clinical requirements [ 301 , 302 ].…”

Black phosphorous nanomaterials as a new paradigm for postoperative tumor treatment regimens

“…Enhancing ALP activity in human mesenchymal stem cells to promote their osteogenic differentiation [115] PLGA shell Sr 2+ ions PTT-triggered Sr 2+ release, phosphonate/phosphate supplementation [118] Hydroxyapatite scaffolds Zn 2+ ions PTT-triggered Zn 2+ release, phosphonate/phosphate supplementation, Zn-sensitized antibacterial effect [119] PLLA electrospun fibrous scaffold BMP2 BP-enhanced biomineralization, BMP2-enhanced recruitment of osteoblast precursor cells [120] Mg implants with BP and PLGA double coating dexamethasone Dexamethasone-enhanced osteogenic effects [121] Aptamer-functionalized matrix vesicles No Aptamer-mediated osteoblast targeting effects, BPenhanced biomineralization [126] PLLA nanofibrous scaffold HA-SiO 2 nanoparticles Porous structures enable migration and infiltration of bone marrow-derived mesenchymal stem cells, PTT-induced release of bone nutrients [127] ECM-mimetic hydrogel Calcium phosphate nanoparticles PTT-induced release of bone nutrients [128] Gelatin-arginine hydrogel No Sustained P supplementation [129] Fig healing would require abundant and continuous supply of bone-related nutrients, especially phosphate ions and calcium (Table 4). Interestingly, photothermal-capable BP-based nanomaterials present multiple features that are highly relevant for guiding and enhancing bone regeneration to repair the postoperative bone defects.…”

“…The released Zn 2+ ions could not only promote local osteogenesis but also enhance the photothermal susceptibility of peri-implant bacteria through inducing envelope stress, thus minimizing the risk of post-implantation infection. In addition to metal ions, BP nanosheets could also be used as the carrier substrate for small-molecule bone regeneration stimulants such as bone morphogenetic protein 2 (BMP-2), therapeutic peptides and dexamethasone [120][121][122]. Nevertheless, it is worth noting that bone tumor is a highly complex disease and the potential impact of these bone regeneration stimulants on tumor cells is still poorly understood.…”