Yiqian Huang

Bio: Yiqian Huang is an academic researcher from Beijing University of Chemical Technology. The author has contributed to research in topics: Bone regeneration & Medicine. The author has an hindex of 8, co-authored 20 publications receiving 232 citations.

Calcium silicate scaffolds promoting bone regeneration via the doping of Mg2+ or Mn2+ ion

Abstract: Biodegradation and bioinductivity are important factors to decide scaffold efficiency in inducing tissue regeneration. For bone regeneration, calcium silicate (CS) is attractive for its degradation to release Ca2+ and Si4+ ions, which are inductive for osteogenesis and angiogenesis. The doping of Mg2+ or Mn2+ can further strengthen the capacity of CS bioceramic in promoting osteogenesis and angiogenesis. Therefore, CS scaffolds were made by soaking polymeric foam in precursor sol-gels containing different amounts of doping elements and subsequent calcination. Mechanical properties of the scaffolds were improved by gelatin coating. In comparison with the un-doped scaffold, the Mg-doped scaffolds demonstrated lower compression strengths, while the Mn-doped scaffolds displayed higher compression strengths. The ion doping would decrease the degradation and the ion release rates, showing negative dependence on the doping amounts of Mg2+ or Mn2+. The Mg-doped scaffolds promoted the osteogenic and angiogenic differentiation of bone marrow mesenchymal stromal cells (BMSCs) more efficiently than the Mn-doped scaffolds, and both of them had stronger promotion effects on cell activities than the CS scaffold. In vivo evaluations were conducted using the rat calvarial defect model, from which, significant vascularization and new bone formation were identified with the Mg-doped CS scaffolds being implanted for 12 weeks, and the Mn-doped CS scaffolds displayed slightly inferior results. Both the Mg- and Mn-doped CS scaffolds could enhance bone regeneration more efficiently than the CS scaffold. CS scaffolds doped with bioactive elements were deemed as good candidates for bone tissue engineering benefiting from their adjustable biodegradation and bioinductivity.

Vancomycin- and Strontium-Loaded Microspheres with Multifunctional Activities against Bacteria, in Angiogenesis, and in Osteogenesis for Enhancing Infected Bone Regeneration.

Abstract: Biomaterials that have capacities to simultaneously induce bone regeneration and kill bacteria are in demand because bone defects face risks of severe infection in clinical therapy. To meet the demand, multifunctional biodegradable microspheres are fabricated, which contain vancomycin to provide antibacterial activity and strontium-doped apatite to provide osteocompatibility. Moreover, the strontium component shows activity in promoting angiogenesis, which further favors osteogenesis. For producing the microspheres, vancomycin is loaded into mesoporous silica and embedded in polylactide-based microspheres via the double emulsion technique and the strontium-doped apatite is deposited onto the microspheres via biomineralization in strontium-containing simulated body fluid. Sustained release behaviors of both vancomycin and Sr2+ ions are achieved. The microspheres exhibit strong antibacterial effect against Staphylococcus aureus, while demonstrating excellent cell/tissue compatibility. Studies of differentiation confirm that the introduction of strontium element strengthens the angiogenic and osteogenic expressions of mesenchymal stromal cells. Subcutaneous injection of the microspheres into rabbit's back confirms their effectiveness in inducing neovascularization and ectopic osteogenesis. Finally, an infected rabbit femoral condyle defect model is created with S. aureus infection and the multifunctional microspheres are injected, which display significant antibacterial activity in vivo and achieve efficient new bone formation in comparison with biomineralized microspheres without vancomycin loading. The vancomycin- and strontium-loaded microspheres, being biomineralized, injectable, and biodegradable, are attractive because of their flexibility in integrating multiple functions into one design, whose potentials in treating infected bone defects are highly expected.

Mimicking the electrophysiological microenvironment of bone tissue using electroactive materials to promote its regeneration

Abstract: The process of bone tissue repair and regeneration is complex and requires a variety of physiological signals, including biochemical, electrical and mechanical signals, which collaborate to ensure functional recovery. The inherent piezoelectric properties of bone tissues can convert mechanical stimulation into electrical effects, which play significant roles in bone maturation, remodeling and reconstruction. Electroactive materials, including conductive materials, piezoelectric materials and electret materials, can simulate the physiological and electrical microenvironment of bone tissue, thereby promoting bone regeneration and reconstruction. In this paper, the structures and performances of different types of electroactive materials and their applications in the field of bone repair and regeneration are reviewed, particularly by providing the results from in vivo evaluations using various animal models. Their advantages and disadvantages as bone repair materials are discussed, and the methods for tuning their performances are also described, with the aim of providing an up-to-date account of the proposed topics.

Simultaneous Reduction and Surface Functionalization of Graphene Oxide by MusselInspired Chemistry

Abstract: his study presents a method of simultaneous reduction and surface funcionalization of graphene oxide by a one-step poly(norepinephrine) funcionalization. The pH-induced aqueous functionalization of graphene oxide y poly(norepinephrine), a catecholamine polymer inspired by the robust dhesion of marine mussels, chemically reduced and functionalized graphene xide. Moreover, the polymerized norepinephrine (pNor) layer provided mulifunctionality on the reduced graphene oxide that includes surface-initiated olymerization and spontaneous metallic nanoparticle formation. This facile urface modifi cation strategy can be a useful platform for graphene-based ano-composites.

Short communication Spectrophotometric determination of alendronate in pharmaceutical formulations via complex formation with Fe(III) ions

Abstract: The formation of the complex between alendronate, non-chromophoric bisphosphonate drug important for the treatment of a variety of bone diseases, and iron(III) chloride in perchloric acid solution was studied. The stoichiometric ratio of alendronate to Fe(III) ions in the chromophoric complex was determined to be 1:1. The conditional stability constant was log Kave =4.50 (SD =0.15), indicating that the Fe(III)–alendronate complex is a complex of medium stability. The optimum conditions for this reaction were ascertained and a spectrophotometric method was developed for the determination of alendronate in the concentration range 8.1–162.5 gm l − 1 , the detection limit being 2 gm l − 1 . The method was validated for the direct determination of alendronate in tablet

Metal-Based Nanostructures/PLGA Nanocomposites: Antimicrobial Activity, Cytotoxicity, and Their Biomedical Applications.

Abstract: Among the different synthetic polymers developed for biomedical applications, poly(lactic-co-glycolic acid) (PLGA) has attracted considerable attention because of its excellent biocompatibility and biodegradability. Nanocomposites based on PLGA and metal-based nanostructures (MNSs) have been employed extensively as an efficient strategy to improve the structural and functional properties of PLGA polymer. The MNSs have been used to impart new properties to PLGA, such as antimicrobial properties and labeling. In the present review, the different strategies available for the fabrication of MNS/PLGA nanocomposites and their applications in the biomedical field will be discussed, beginning with a description of the preparation routes, antimicrobial activity, and cytotoxicity concerns of MNS/PLGA nanocomposites. The biomedical applications of these nanocomposites, such as carriers and scaffolds in tissue regeneration and other therapies are subsequently reviewed. In addition, the potential advantages of using MNS/PLGA nanocomposites in treatment illnesses are analyzed based on in vitro and in vivo studies, to support the potential of these nanocomposites in future research in the biomedical field.