| On the one hand,China’s resources in biomedical polymer materials are relatively scarce,and on the other hand,the scalded drug-loaded slow-release film materials are lacking in China.China is a large aquaculture country.The output of fish by-products is huge,of which fish scale production is relatively prominent.Fish scales are rich in collagen and can be used as a new raw material to extract gelatin protein.However,due to the influence of technology and its old ideas,fish scales have not been well developed and used.In this experiment,grass carp fish scales were used as raw materials,and grass carp fish scale gelatin was prepared by the Protease A enzyme method.Further,a grass carp fish scale gelatin chitosan scalded drug-containing sustained-release film was further developed.The main research purposes,methods,results and conclusions are as follows:Objective: To interpret the physical and chemical properties of grass carp fish scale gelatin,the biosafety of grass carp fish scale gelatin scald film and its effect on wound healing,to provide scientific basis for the clinical research of late-stage scald drug-loaded sustained release film,and to promote medical polymer materials and fish The development of secondary industries has played a positive role.Methods: The response surface analysis method was used to evaluate the yield,gel strength and viscosity of grass carp scale gelatin as response values,and the optimal enzymatic hydrolysis conditions of Protease A were analyzed.Based on the determined optimal enzymatic conditions and single-factor experiments,an orthogonal experiment was designed to obtain an optimized process for extracting fish scale gelatin from hot water.The amino acid composition of fish scale gelatin and its comparison with other mammalian gelatin were analyzed using an Agilent 1100 high-performance liquid-phase amino acid automatic analyzer.The relative molecular weight of fish scale gelatin was determined using a Tricine-SDS-PAGE discontinuous electrophoresis system.Gelatin hydrophobicity index S0,Fourier transform infrared spectrometer to measure the infrared absorption spectrum of fish scale gelatin,X-ray diffractometer to measure the X-ray diffraction intensity of fish scale gelatin,and rheometer to measure the gel temperature and melting temperature of thick grass carp scale gelatin.According to the film-forming properties of grass carp fish scale gelatin,a fish scale gelatin film was prepared,and the optimal film-forming medium and the best film-forming conditions were determined according to the mechanical properties,air permeability,surface evaporation,and water absorption of the film.The content of resveratrol in Polygonum cuspidatum extract was determined by HPLC method,and the added amount of Polygonum cuspidatum extract was determined.New Zealand rabbits and Kunming mice were used as experimental subjects to study the biosafety of the diaphragm and its role in promoting healing.Results: The optimum conditions for enzymolysis were: the time of enzymolysis was 5h,the temperature of enzymolysis was 35 ° C,and the amount of enzyme added was 0.15%(w / w).The best extraction process is: the extraction temperature is 55 ° C,the extraction time is 5h,and the p H of the extraction is 6.5.The properties of extracted grass carp fish scale gelatin were measured and found that the content of sub-amino acids in grass carp fish scale gelatin accounted for 24.1%,which was lower than that of pig skin gelatin extracted by acid method and beef bone gelatin extracted by subtraction,and higher than that of sea fish skin.content.There are two distinct α bands in grass carp scale gelatin,namely α1 subunit 124,000 Da,α2 subunit 108,000 Da,and the conformation ratio of α1 + α2 is about 40.21%.Therefore,most of the spatial conformation of grass carp scale gelatin is single The left-handed helix conformation and a small portion of the three-helix conformation had two diffraction peaks,7.878 respectively.And 19.939.The surface hydrophobicity index S0 of grass carp fish scale gelatin was 217.23,and the gel temperature and melting temperature were 21.3°C and 27.8°C,respectively.According to the nature of the diaphragm,it was found that the film forming medium of fish scale gelatin film was a smooth plastic plate,and the film formation conditions were: the concentration of grass carp fish scale gelatin solution was 20 mg / ml,and the amount of glycerol added was 30%),The ratio of fish scale gelatin to chitosan was 4: 1 when preparing the fish scale gelatin chitosan composite film.At the same time,according to the dissolution curve of the drug-loaded sustained release film,it was determined that when the added amount of Polygonum cuspidatum extract was 30%,the maximum drug load of the film had been reached.The results of the biosafety evaluation revealed that the five membranes prepared from grass carp fish scale gelatin all met the requirements for the safety level of biological materials.At the same time,according to the results of deep Ⅱ degree scald on New Zealand rabbits by the diaphragm,all five diaphragms can significantly promote the exfoliation and healing of scald wounds(P <0.05),and can significantly increase the expression of hydroxyproline(P <0.05).And the peak is ahead.And compared with the positive group of medical chitosan antibacterial film,the experimental group grass carp scale gelatin chitosan knotweed slow-release film,chitosan knotweed slow-release film group has stronger healing promoting effect,the experimental group grass carp scale gelatin film,grass carp scale gelatin The effects of chitosan film composite film and grass carp fish scale gelatin knotweed sustained-release film group were lower than those of the positive control group,but higher than those of the negative control group.Conclusion: Based on the analysis of comprehensive experimental results,it was found that the scale-forming gelatin extracted from grass carp fish scales using the metal peptidase Protease A had better film-forming properties.Good biological activity,its pro-healing effect is higher than that of the positive control group,there is no obvious scar on the wound surface after scald repair,and it is a potentially safe scald release film.Although grass carp fish scale gelatin chitosan composite film has a lower healing effect than the positive control group,its biosafety performance is better,and it can be regarded as a safe new medical polymer material. |
