| Currently,serious skin damages caused by burn wounds,scald wounds and chronic wounds with several complications such as infection represent a major and persistent burden in orthopedics and dermatology.In recent years,the investigation of wound dressings is getting more and more popular among researchers.One of the effective strategies is developing novel dressings with many functions such as anti-infection and promoting healing.Bacterial cellulose（BC）is nano-biomaterial that has meticulous three-dimensional network structure,excellent air permeability,great tensile strength and good biocompatibility.And it is widely used recently.But its antibacterial properties and healing properties are not ideal.Hydroxypropyltrimethyl ammonium chloride chitosan（HACC）is a natural antibacterial agent which has good biocompatibility and antibacterial ability,especially negative effects on Staphylococcus aureus.Collagen（COL-Ⅰ）posesses incomparable biocompatibility and bioactivity,and contains cell recongnition factors such as RGD peptides which is an important constituent of human body.In this study,we have developed a new artificial mesh and modified bacterial cellulose with collagen and hydroxypropyl trimethyl hydroxypropyltrimethyl ammonium chloride chitosan,which has excellent biocompatibility,bioactivity and antibacterial property.In this paper,HACC/BC composite materials with different content of HACC were prepared by biological compound method,and HACC/COL-Ⅰ/BC composite materials were prepared by the method of in-situmembrane liquid interface culture.The microstructure,composition and crystal structure of the composites were observed by Scanning Electron Microscopy（SEM）,Energy Dispersive Spectroscopy（EDS）,Infrared Spectroscopy（FTIR）and X-ray diffraction.Morever,the properties of the composite materials are understood by means of mechanical properties,water management system performance,porosity and heat stress analysis.The antimicrobial properties and cell biological properties of the composite membranes were investigated by bacterial experiment and cell experiment.Specific research works were as follows:（1）HACC/BC composite films with three kinds of HACC content,HBC-1（13.6%）,HBC-2（37.3%）,HBC-3（62%）,were fabricated by the method of biosynthesis.And the SEM,EDS and FTIR analysis showed that HACC was successfully combined into BC fiber network structure.The distribution of chitosan quaternary ammonium salt in HACC/BC composite was uniform,and HACC content was different,its effective recombination rate was increasing along with the increase of the content of HACC,but the effective compound rate decreaseed at HBC-3;Compared with pure BC,HACC/BC composites showed better performance of water management.The porosity of HBC-1,HBC-2,and HBC-3 was 83.2%,77.1%,and 74.28%respectively.The mechanical properties of HACC/BC composites were great.The thermal stability analysis showed that the thermal stability of the composite is changed from first-order pyrolysis to two-stage pyrolysis due to the existence of HACC.The antibacterial results showedthat the antibacterial effect of HACC/BC composite on Staphylococcus aureus wass good,and the antibacterial effect was more obvious with the increase of HACC content.However,the antibacterial effect of HBC-3 and HBC-2 had no obvious difference.The effective recombination rate of HBC-3 was 4.54%,while the effective recombination rate of HBC-2 was 7.71%which wass higher than that of HBC-3,after a comprehensive analysis,the choice HBC-2 for the antimicrobial dressing was more reasonable to avoid drug waste.The results of cell experiments showed that HBC-1 and HBC-2 did not affect cell proliferation,and HBC-3 had a negative effect on cell proliferation.（2）HACC and COL-Ⅰcompound to the three-dimensional network of BC by the method of in-situ membrane liquid interface.The results of SEM and FTIR showed:HACC/COL-Ⅰ/BC composite film still presented 3D nano-network structure,HACC and COL-Ⅰevenly adsorbed on BC fiber.HACC/COL-Ⅰ/BC’s water absorption,swelling property and water retention property were better than BC film.Water vapor transmittance of HACC/COLI/BC film was 3084.52g·m-2·24-1.Porosity of HACC/COLI/BC film was 80.96%and the stress of HACC/COLI/BC film was 15.85 MPa.Strain of HACC/COLI/BC film was 27.63%.The young’s modulus of HACC/COLI/BC film was 200.84 MPa.It also had good thermal stability,The bacteriostatic ring width was 0.92 mm of HACC/COL-Ⅰ/BC composite membrane.It exhibited fantastic antibacterial property.In terms of cell biology,compared with the BC and HACC/BC films,HACC/COL-Ⅰ/BC composite membrane could better promote the proliferation of NIH3T3.The results of bacterial and cell experiments showed that HACC/COL-Ⅰ/BC composite membrane has good antibacterial properties and performance of cell biology. |
