用微相吸附-光谱修正(MPASC)新技术研究核酸与多色蓝(PCB)探针分子间的相互作用,分析核酸分子内双静电膜的形成与 Langmuir吸附的关联性.通过pH 7.24的介质核酸-PCB反应的光谱研究,测定了结合产物的物理化学参数:结合比IPCB:2DNA-PCB、IPCB:3RNA-PCB,平衡常数KDNA-PCB=5.42 X 104,KRNA-PCB=2.82 x 104,摩尔吸收系数ε(DNA-PCB,625nm)=5.65x103(mol-1·L)·cm-1,ε(RNA-PCB,625nm)=3.85x103(mol-1·L)·cm-1结果表明,RNA分子仅形成约60%双螺旋结构链,核酸双螺旋每一周期的负静电沟最大聚集10个PCB分子.该吸附反应用于核酸样品测定,结果良好.
[ Object] The aim was to discuss the pollution status of polycyclic aromatic hydrocarbons (PAHs) in mussels from the middle and lower main stream of Huaihe River, which will provide a scientific basis for dietary safety of mussels. [ Method] Suspended matter, sediment, and mussel samples were collected from Wuxiaojie and Fushanji in middle and lower reaches of Huaihe River. All samples were extracted with Soxhlet, separated through Silica GeI-Al2O3 column, and determined by GC-MS, and then 16 typical PAHs contents in the prior table listed by American EPA were obtained. [ Result] The results indicated that total PAHs concentrations in suspended matters and sediments of Wuxiaojie were significantly higher than those in Fushanji respectively. However, PAHs concentrations in mussels of the two samplings showed little difference; as for single PAH component, low-ring PAHs were more advantaged in suspended matters of two sampling sites, while high-ring PAHs were more advantaged in mussels. PAHs in sediments of Wuxiaojie assumed low-ring aspect, though PAHs in sediments of Fushanji assumed high-ring aspect. [ Conclusion] In spite of that sediments and mussels were not yet contaminated according to the ecological risk assessment of PAHs, its potential hazards couldn't be ignored any more.