Department of Chemical and Materials Engineering, University of Alberta, Edmonton, Alberta, Canada.
Biophys J. 2009 Dec 16;97(12):3054-64. doi: 10.1016/j.bpj.2009.08.058.
Biomechanical models for biological tissues such as articular cartilage generally contain an ideal, dilute solution assumption. In this article, a biomechanical triphasic model of cartilage is described that includes nondilute treatment of concentrated solutions such as those applied in vitrification of biological tissues. The chemical potential equations of the triphasic model are modified and the transport equations are adjusted for the volume fraction and frictional coefficients of the solutes that are not negligible in such solutions. Four transport parameters, i.e., water permeability, solute permeability, diffusion coefficient of solute in solvent within the cartilage, and the cartilage stiffness modulus, are defined as four degrees of freedom for the model. Water and solute transport in cartilage were simulated using the model and predictions of average concentration increase and cartilage weight were fit to experimental data to obtain the values of the four transport parameters. As far as we know, this is the first study to formulate the solvent and solute transport equations of nondilute solutions in the cartilage matrix. It is shown that the values obtained for the transport parameters are within the ranges reported in the available literature, which confirms the proposed model approach.
生物组织（如关节软骨）的生物力学模型通常包含理想稀溶液假设。本文描述了一种软骨的生物力学三相模型，该模型包括对浓缩溶液（如生物组织玻璃化过程中应用的溶液）的非稀处理。三相模型的化学势方程进行了修正，并且针对体积分数和溶质摩擦系数进行了调整，这些参数在这种溶液中不可忽略。四个传输参数，即水渗透率、溶质渗透率、软骨内溶剂中溶质的扩散系数和软骨刚度模量，被定义为模型的四个自由度。使用该模型模拟了软骨中的水和溶质传输，并将平均浓度增加和软骨重量的预测拟合到实验数据中，以获得四个传输参数的值。据我们所知，这是首次在软骨基质中制定非稀溶液的溶剂和溶质传输方程的研究。结果表明，所得到的传输参数值在可用文献中报道的范围内，这证实了所提出的模型方法。
