Tatevossian A, Newbrun E
Arch Oral Biol. 1983;28(2):109-15. doi: 10.1016/0003-9969(83)90117-6.
The tracer diffusion of small ionic species was investigated in water, saliva, dental plaque fluid and in plaque residue packed by a range of g forces. Diffusion rate of NaCl was similar in water, saliva and plaque fluid. The rate of CaCl2, NaH2PO4, Na2HPO4 and Na2SO4 was less in both saliva and plaque fluid. Diffusion rate of all ionic species tested was significantly less in plaque residue, most of all for CaCl2. In plaque fluid, plaque residue and water, an inverse linear relationship was found between log diffusion coefficients and log molecular weights. Increasing the tortuosity of the diffusion path, by packing plaque residue, further reduced the diffusion rate of NaH2PO4 and NaHCO3. In terms of three-dimensional diffusion, in plaque fluid, NaH2PO4, Na2HPO4 and CaCl2 diffused a distance of 300 microns within 25 s, whereas in plaque residue the equivalent diffusion times were 1.5-5.7 min. The unique retardation of CaCl2 in plaque residue implicated both non-specific and specific binding interactions.
研究了小离子物种在水、唾液、牙菌斑液以及一系列重力作用下填充的菌斑残渣中的示踪扩散。氯化钠在水、唾液和菌斑液中的扩散速率相似。氯化钙、磷酸二氢钠、磷酸氢二钠和硫酸钠在唾液和菌斑液中的扩散速率均较低。所有测试离子物种在菌斑残渣中的扩散速率显著降低，其中氯化钙最为明显。在菌斑液、菌斑残渣和水中，发现对数扩散系数与对数分子量之间呈反线性关系。通过填充菌斑残渣增加扩散路径的曲折度，进一步降低了磷酸二氢钠和碳酸氢钠的扩散速率。就三维扩散而言，在菌斑液中，磷酸二氢钠、磷酸氢二钠和氯化钙在25秒内扩散了300微米的距离，而在菌斑残渣中，等效扩散时间为1.5 - 5.7分钟。氯化钙在菌斑残渣中的独特阻滞涉及非特异性和特异性结合相互作用。
