Clark A, Clark P A
Biophys J. 1983 Apr;42(1):25-30. doi: 10.1016/S0006-3495(83)84365-3.
A useful technique in studying the saturation of hemoglobin in erythrocytes or myoglobin in tissue is cryophotometry, in which tissue is frozen for later spectrophotometric analysis. A general question associated with this technique is whether the freezing process alters the chemical state. This paper presents a theoretical analysis of the simplest model relevant to that question. We study the effect of rapid cooling on a spatially homogeneous chemical reaction. The analysis shows that changes during freezing are negligible near the boundary to which the heat sink is applied, but can be significant deeper in the sample. The distance from the boundary at which the changes during freezing become appreciable can be expressed simply in terms of the chemical reaction rates and the thermal diffusivity of the tissue. Detailed results are given for the case of oxygen and myoglobin in skeletal muscle.
研究红细胞中血红蛋白或组织中肌红蛋白饱和度的一种有用技术是低温光度法，即把组织冷冻起来以便日后进行分光光度分析。与该技术相关的一个普遍问题是冷冻过程是否会改变化学状态。本文给出了与该问题相关的最简单模型的理论分析。我们研究了快速冷却对空间均匀化学反应的影响。分析表明，在施加散热器的边界附近，冷冻过程中的变化可忽略不计，但在样品更深的部位可能会很显著。冷冻过程中变化变得明显的边界距离可以简单地根据化学反应速率和组织的热扩散率来表示。给出了骨骼肌中氧气和肌红蛋白情况的详细结果。
