基于CT图像低温保护剂在大鼠肾脏中扩散特性的研究

Research on the Diffusion of Vs55 Permeability in Rat Kidneys Based on Computer Tomography

低温保护剂(CPA)被广泛应用于生物组织材料的低温保存,而评估低温保护剂在生物组织中加载的均匀性是生物组织冷冻保存的关键问题之一。本文以大鼠肾脏为研究对象,采用计算机断层扫描成像(CT)研究了不同浓度Vs55在不同温度下肾脏渗透的传质特性,并结合相关理论研究其有效扩散系数(Deff)。结果表明:加载浓度越高,扩散速率越快;Vs55渗透摩尔浓度为8.4 mol/L,加载温度为4、22、37℃时,扩散速率分别为1.77×10^-6、2.94×10^-6、3.93×10^-6 cm^2/s。同时,建立了Vs55在肾脏中的扩散模型并验证扩散速率的有效性,决定系数(R2)和平均相对偏差(MRE)的范围分别为0.960~0.993和3.07%~6.74%。

Cryopreservation is the usual method for long-term preservation of natural and engineered tissues.However,homogeneous loading of tissues with CPAs constitutes one of the major hurdles in tissue cryopreservation.In this study,computer tomography(CT)was used as a non-invasive imaging method to determine the effective diffusion of Vs55 in tissue-engineered collagen scaffolds,and the effective diffusion constant(Deff)was calculated by the theoretic model.The kidney activation energy was calculated according to the effective diffusion constant obtained by CT.The results demonstrated that the higher the loading concentration,the faster the rate of diffusion.When Vs55 concentration was 8.4 mol/L,the diffusion rates were 1.77×10^-6 cm^2/s at 4℃,2.94×10^-6 cm^2/s at 22℃,and 3.93×10^-6 cm^2/s at 37℃,respectively.The model was demonstrated to predict the spatial and temporal distribution of Vs55 in the kidney.The coefficient of determination(R2)and the mean relative error(MRE)were 0.960-0.993 and 3.07%-6.74%,respectively.This observation was temperature-dependent,with slower permeation at lower temperatures.This study demonstrated the effectiveness of CT to measure Vs55 permeation into rat kidney.