罗丹明B自组装膜对单、双链脱氧核糖核酸的荧光识别

Fluorescent Recognition of Single-and Double-Stranded Oligonucleotides Based on Rhodamine B-Modified Self-assembled Bilayers

通过静电吸引作用将罗丹明B(RB)组装在硅烷化的石英基底上,构建了修饰有RB的双层自组装膜Quartz/APES/RB。在三羟甲基氨基甲烷-盐酸(Tris-HCl)缓冲液(pH7.4)中,利用荧光分光光度法研究了Quartz/APES/RB与单、双链DNA的相互作用。考察了自组装膜的组装条件、膜性质及对单、双链DNA的作用机理。实验表明,Quartz/APES/RB对单、双链DNA检出限分别为2.4 ng/L和0.85 ng/L,可应用于痕量单、双链DNA的荧光识别。

Rhodamine B （RB） was assemblied onto the surface of quartz substrate by the electrostatic interaction between the fluorescence reagent RB and T-aminopropyltriethoxysilane （ APES）, and quartz/APES/RB film was constructed. We have studied the fluorescence spectra and binding reaction of quartz/APES/RB with single- and double-stranded oligonucleotides（ ssDNA and dsDNA）in Tris-HC1 buffer solution of pH 7.4. The condition of establishment, characterization of self-assembled bilayers, and binding reaction mechanism between DNA and ouartz/APES/RB were discussed. The results of the experiment show that ouartz/APES/RB was allowed for an extremely highly sensitive fluorescent recognition for ssDNA and dsDNA with a detection limit of 2.4 ng/L and 0. 85 ng/L, respectively.