Reconstruction of hydrogel geometric network based on fluorescent images and finite element simulation of its mechanical properties
Objective To investigate the feasibility of reconstructing the geometric network of hydrogels from fluorescent images and its feasibility of finite element modeling.Method Gelatin hydrogels were prepared from a cold-water fish skin gelatin aqueous solution,cross-linked with 28.2,56.5,113.0,and 141.0 mg of glutaraldehyde for 16 hours.The mechanical properties of each group of gelatin hydrogels were measured using dynamic mechanical analysis,and the compressive modulus(Emeas)was calculated.The pore structures of each group of gelatin hydrogels were observed and analyzed using laser confocal microscopy and image segmentation programs.Three-dimensional reconstruction of the hydrogel scaffold geometric models was performed using image segmentation and the marching cubes algorithm.The fluorescent images of the hydrogels were pre-processed,segmented,reconstructed,and optimized.Finite element analysis was conducted using ANSYS Workbench,employing static structural analysis to simulate the compression tests of each group of hydrogels.The compressive modulus(Esim)and load distribution of the hydrogel structures were calculated from the simulations.Results Dynamic mechanical analysis provided stress-strain data for the hydrogels,yielding Emeas values of(457.0±30.8)Pa,(942.7±260.5)Pa,(2 053.3±115.0)Pa,and(2 133.3±125.8)Pa.Observations indicated that the pore structure of the glutaraldehyde-crosslinked hydrogels changed,with higher glutaraldehyde concentrations resulting in smaller pore sizes and increased pore numbers.The 3 D reconstruction program generated geometric models of the hydrogels suitable for finite element meshing.The finite element simulation results for Esim were consistent with Emeas,producing values of 447.2 Pa,829.9 Pa,1 987.7 Pa,and 2,181.6 Pa,respectively.The finite element analysis indicated that the load-bearing capacity of the hydrogel structure increased,with the fiber network bearing a greater proportion of the load compared to the matrix.As the elastic modulus of the matrix increased,the stress distribution at the fiber-matrix interface became more uniform,and the matrix shared a larger portion of the load compared to the fiber network.Conclusion The three-dimensional reconstruction method successfully constructed geometric models of the hydrogels.The finite element models simulated the mechanical properties of the gelatin hydrogels accurately,reflecting their compression behavior effectively.
finite element analysishydrogelbiomechanical phenomenaimage segmentation3 D reconstructionmechanical analysis
万方数据
维普
