title: Covalently antibacterial alginate-chitosan hydrogel dressing integrated gelatin microspheres containing tetracycline hydrochloride for wound healing.
abstract: An antibacterial and biodegradable composite hydrogel dressing integrated with microspheres is developed for drug delivery and wound healing. The mechanism of gelation is attributed to the Schiff-base reaction between aldehyde and amino groups of oxidized alginate (OAlg) and carboxymethyl chitosan (CMCS). To enhance antibacterial and mechanical properties, tetracycline hydrochloride (TH) loaded gelatin microspheres (GMs) were fabricated by an emulsion cross-linking method, followed by integrating into the OAlg-CMCS hydrogel to produce a composite gel dressing. In vitro gelation time, swelling, degradation, compressive modulus and rheological properties of the gel dressing were investigated as the function of microsphere ratios. With increasing ratios of microspheres from 10 to 40mg/mL, the composite dressing manifested shorter gelation time and lower swelling ratios, as well as higher mechanical strength. Comparing to other formulations, the gel dressing with 30mg/mL microspheres showed more suitable stabilities and mechanical properties for wound healing. Also, in vitro drug release results showed that the loaded TH could be sustained release from the composite gel dressing by contrast with pure hydrogels and microspheres. Furthermore, powerful bacteria growth inhibition effects against Escherichia coli and Staphylococcus aureus suggested that the composite gel dressing, especially the one with 30mg/mL GMs containing TH, has a promising future in treatment of bacterial infection.
authors: School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
authors: Huinan
authors: H
authors: Chen
authors: School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China. Electronic address: xingxiaodong07@njust.edu.cn.
authors: Xiaodong
authors: X
authors: Xing
authors: School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China. Electronic address: hptan@njust.edu.cn.
authors: Huaping
authors: H
authors: Tan
authors: School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
authors: Yang
authors: Y
authors: Jia
authors: School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
authors: Tianle
authors: T
authors: Zhou
authors: Department of Orthopaedics, Jinling Hospital, Nanjing 210002, China.
authors: Yong
authors: Y
authors: Chen
authors: Department of Orthopaedics, Jinling Hospital, Nanjing 210002, China.
authors: Zhonghua
authors: Z
authors: Ling
authors: School of Material Engineering, Jinling Institute of Technology, Nanjing 211169, China.
authors: Xiaohong
authors: X
authors: Hu
mesh_terms: D000464:Alginates / Q000737:chemistry*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D001458:Bandages; D048271:Chitosan / Q000737:chemistry*; D019245:Compressive Strength; D055119:Elastic Modulus; D005612:Freeze Drying; D005780:Gelatin / Q000737:chemistry*; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate / Q000138:chemical synthesis / Q000737:chemistry*; D007700:Kinetics; D008826:Microbial Sensitivity Tests; D008863:Microspheres; D012212:Rheology; D017550:Spectroscopy, Fourier Transform Infrared; D013314:Stress, Mechanical; D013499:Surface Properties; D013752:Tetracycline / Q000494:pharmacology*; D013997:Time Factors; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D000464:Alginates; D000900:Anti-Bacterial Agents; D006603:Hexuronic Acids; D020136:Hydrogel, Polyethylene Glycol Dimethacrylate; D020723:Glucuronic Acid; D005780:Gelatin; D048271:Chitosan; D013752:Tetracycline
keywords: Antibacterial activity; Bacterial infection; Hydrogel; Microspheres; Wound dressing