title: Engineering bio-adhesive functions in an antimicrobial polymer multilayer.
abstract: Functionalization of a biomaterial surface with adhesive ligands is an effective way to promote specific cell adhesion. Ideally, biomaterial for applications in biomedical implants should simultaneously promote host cell adhesion and inhibit bacterial adhesion. Currently, little attention has been paid to the design of antimicrobial biomaterial with selective adhesiveness towards only targeted cells or tissues. In this study, the role of two typical adhesive ligands on the bioadhesion functions of a model antimicrobial film was elucidated. First, an adhesive ligand including an RGD peptide or collagen (CL) was chemically coupled to an antimicrobial polymeric multilayer composed of dextran sulfate (DS) and chitosan (CS). It was demonstrated that the density of RGD and CL immobilized on the DS/CS multilayer ranges between 4 to 137 ng cm(-2) and 100 to 1000 ng cm(-2), respectively. Then the effect of immobilized RGD or CL on both bacterial and fibroblast adhesion was investigated. By determining the density and morphology of adherent fibroblast on a DS/CS multilayer with or without an adhesive ligand, it was shown that RGD or CL effectively promoted fibroblast adhesion and proliferation in a concentration-dependent manner. Interestingly, the type of adhesive ligands imposed distinct effects in bacterial adhesion. Immobilized RGD did not enhance Staphylococcus aureus and Escherichia coli adhesion on DS/CS multilayers under all concentrations. In contrast, CL triggered significant S. aureus adhesion on DS/CS multilayers even at low surface concentration and when fibroblast adhesion was absent. Moreover, the detachment forces of individual S. aureus on CL coated DS/CS multilayers probed by atomic force microscopy (AFM) was 3 times and 20 times higher than that on the control substrate and on unmodified DS/CS multilayers, respectively. Interestingly, the lowest detachment force of E. coli was found on the CL coated DS/CS multilayers. This study demonstrated the possibility of engineering an antimicrobial multilayer coating with tailored adhesive properties towards specific cell types for potential applications in biomedical implants.
authors: Institute of Materials Research and Engineering, A*STAR (Agency for Science, Technology and Research), 3 Research Link, 117602, Singapore.
authors: Tao
authors: T
authors: He
authors: Ying
authors: Y
authors: Zhang
authors: Alvin C K
authors: AC
authors: Lai
authors: Vincent
authors: V
authors: Chan
mesh_terms: D016475:3T3 Cells; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry*; D001422:Bacterial Adhesion; D001672:Biocompatible Materials / Q000737:chemistry*; D002448:Cell Adhesion; D049109:Cell Proliferation; D048271:Chitosan / Q000737:chemistry; D003094:Collagen / Q000737:chemistry; D016264:Dextran Sulfate / Q000737:chemistry; D004926:Escherichia coli / Q000166:cytology; D005347:Fibroblasts / Q000166:cytology; D008024:Ligands; D051379:Mice; D018625:Microscopy, Atomic Force; D018613:Microscopy, Confocal; D009842:Oligopeptides / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D013211:Staphylococcus aureus / Q000166:cytology; D013499:Surface Properties; D023822:Tissue Engineering
chemical_list: D000890:Anti-Infective Agents; D001672:Biocompatible Materials; D008024:Ligands; D009842:Oligopeptides; D011108:Polymers; C047981:arginyl-glycyl-aspartic acid; D003094:Collagen; D048271:Chitosan; D016264:Dextran Sulfate