脱氧核糖核酸(DNA)是生物的基本遗传物质,生物样品中特定DNA序列的测定在生物医学领域应用广泛[1].在众多检测DNA的方法中,荧光检测法因其方法简单、选择性良好而受到广泛关注.荧,
Fluorescent self-assembly multilayers(SAMs) Quartz/PDDA/PSS/PDDA/CdTe/ssDNA,with ssDNA fixed onto the outermost layer were designed.The SAMs were fabricated onto the quartz surface using CdTe quantum dots(QDs) as a fluorescence probe,which can effectively sense biomolecules by fluorescence resonance energy transfer(FRET) from QDs to graphene oxide(GO).GO can quench fluorescence of SAMs.When tDNA was added,upon the strong interaction between ssDNA and tDNA,tDNA was accumulated on the surface of SAMs in place of GO.The distance between the SAMs and GO increased,which significantly hindered the FRET between CdTe and GO.Thus,the fluorescence of CdTe increased with tDNA adding.The constructed ssDNA SAMs could be sensing for tDNA at the solid-liquid interface with extremely high sensitivity.A good linear relationship between the relative fluorescence intensity F/F0 and concentration of tDNA is obtained in the range from 7.00×10-13 to 2.13×10-11 mol/L,the detection limit is 7.26×10-14 mol/L.