二溴羟基卟啉与核酸相互作用的光谱行为研究

研究了meso-4(3,5-二溴-4-羟基苯基)卟啉(T(DBHP)P)与小牛胸腺DNA (ct DNA)相互作用的光谱行为，探讨了以T(DBHP)P作为光谱探针测定核酸的最佳条件及作用机理。在 pH 4.92 HAc-NaAc缓冲液中，T(DBHP)P在最大吸收波长425 nm处的吸收峰强度显著下降，且下降程度与ct DNA含量呈线性关系，ct DNA含量在0.20～1.80 μg·mL-1范围内符合比尔定律，检出限为0.024 μg·mL-1。实验中发现Tween-80微乳液的加入能显著增加体系的灵敏度。同时，用摩尔比法测定了DNA与卟啉的结合数为21，并初步探讨了反应机理。

Study on Spectral Behavior of Meso-Tetra-(3,5-Dibromo-4-Hydroxyphenyl)Porphyrin with Calf Thymus DNA

The binding characteristics of meso-tetra-(3, 5-dibromo-4-hydroxphenyl) porphyrin [T(DBHP)P] with calf thymus DNA (ct DNA) in pH 4.92 HAc-NaAc buffer solution were studied by the techniques of spectrophotometry. At the maxium absorption wavelength for T(DBHP)P, the decrease in the absorbance was linear with the amount of ct DNA. The experiments indicated that under optimum conditions, ct DNA obeys Beer's law in the range of 0.20-1.80 microg x mL(-1), and the limit of detection is 0.024 microg x mL(-1). Tween-80 microemulsion was commended in the experiment for better sensitivity. Furthermore, the association number is also determined by molar ratio method. The interactional mechanism between ct DNA and (T(DBHP)P was investigated as well.