对-二甲胺基亚苄罗丹宁与植物DNA的显色反应研究

Study on the Interaction Between DNA and p-Dimethylaminobenzylidene Rhodanine

在pH9．5的NH3-NH4Cl缓冲溶液中，对-二甲胺基亚苄罗丹宁（p-DBR）与DNA形成橙色复合物，λmax为480nm，表观摩尔吸光系数为1．32×10^7L·mol^-1·cm^-1。当无CTMAB存在时，DNA对p-DBR的最大结合数N为34，有CTMAB存在时N为204。DNA与p—DBR的作用符合Scatchard模式。利用DNA-p—DBR复合物可测定植物DNA提取液中DNA的含量。方法线性范围为1．25～7．50mg／L，相对标准偏差（RSD）为2．9％。

In a pH 9. 5 buffer solution, DNA formed an orange complex with p-dimethylaminobenzylidene rhodanine,and the molar absorptivity is 1.32×10^7L·mol^-1·cm^-1 at 480 nm. The maximum binding number between DNA and p DBR was 34 in the absence of CTMAB,and 204 in the presence of CTMAB. The Scatchard model was appropriate without CTMAB. The proposed method was used for the determination of DNA in extracted plant DNA solution. Beer＇s law was obeyed in a range from 1.25 mg/ L to 7.50 mg/L of DNA.