Preparation And Properties Of Gelma-HEMA-HEAA Hydrogel Medical Adhesive

The traditional method to close wound is mostly using surgical suture which has many disadvantages such as damage to the tissue around,long recovery period,and easy infection.Researchers found that medical adhesives can replace needle sutures to close the wound.However,most of the existing medical adhesives on the market have shortcomings such as insufficient strength,viscosity failure during the bonding process,or toxic degradation products which limit it’s application.To solve these problems,the article synthesize a light-curing hydrogel with good biocompatibility and controllable polymerization based on methacryloyl gelatin(GelMa).Hydroxyethyl methacrylate(HEMA),N-Hydroxyethyl acrylamide(HEAA)were blended to prepare a light-curing composite hydrogel medical adhesive with excellent mechanical strength,adhesive properties and biocompatibility.In this paper gelatin is modified with different content of methacrylic anhydride(MA)to synthesize GelMa with different degrees of methacryloyl substitution.The characteristic peaks are characterized by the hydrogen nuclear magnetic spectrum.The characteristic peak areas are integrated to quantitatively calculate the methacrylic acid of GelMa.When the methacrylic substitution degree of GelMa is 52% the largest shear strength reaches 87 k Pa.In order to improve the mechanical strength of GelMa,HEMA is added to the system to synthesize GelMa-HEMA medical adhesive.The surface morphology,tensile strength,water content and antibacterial properties were characterized by scanning electron microscopy,tensile test,water content test and antibacterial experiment.The results show that when adding 20% GelMa,20% HEMA,1.2% I2959,and irradiating for 20 minutes,the strength of the hydrogel can reach up to 452 k Pa.At the same time,the water content drops to 30% at room temperature for 30 hours.To improve the moisture of GelMa-HEMA hydrogel at room temperature and bonding strength we synthesize GelMa-HEMA-HEAA hydrogel medical adhesive by light curing.Through tensile test,pigskin bonding experiment and shearing experiment,the properties of HEAA,HEMA,GelMa,initiator concentration and light duration on hydrogel tensile strength,pigskin adhesion,glass adhesion and other properties were examined.Rheological experiments,swelling performance test and water content test were used to research the storage modulus,swelling capacity and water retention performance of the hydrogel.The results show that the tensile strength of the hydrogel is up to 330 k Pa.Adhesion force of pigskin reaches 159 k Pa.Shear strength of the glass sheet is 1.8 MPa.Storage modulus is 3MPa.Swelling rate is within 800%.Moisture content is above 50%.Finally,the biological performance of GelMa-HEMA-HEAA hydrogel was investigated through cell proliferation,antibacterial experiments and inflammatory factor detection.Results show that GelMa-HEMA-HEAA hydrogel has no cytotoxicity and has certain antibacterial effects against Bacillus subtilis(Gram-positive bacteria)and Escherichia coli(Gram-negative bacteria).Through the rat wound closure experiment we found that G-H-H hydrogel can improve the wound healing speed and inhibit the hyperplasia of scar tissue.ELISA inflammatory factor test results show that G-H-H hydrogel has no obvious inflammatory effect on rats and has good biocompatibility.