Non-covalent anionic porphyrin functionalized multi-walled carbon nanotubes as an optical probe for specific DNA detection.
With water-soluble anionic tetra (p-carboxyphenyl) porphyrin (TCPP) to solubilize multi-walled carbon nanotubes (MCNTs), we obtained a suspension that could be stable more than 1 week. With this TCPP/MCNTs suspension, we propose a spectrofluorometric method of DNA hybridization in this contribution. Our basic finding for this work is that the fluorescence from a dye-tagged single stranded DNA (ssDNA), which was directly added to the TCPP/MCNTs suspension, gets quenched, and the fluorescence could be remained if the dye-tagged single stranded DNA is first to be hybridized with its complementary target DNA to form a double stranded DNA (dsDNA) hybrid and added into the TCPP/MCNTs suspension. Mechanism investigations showed that the reason for the former is due to the adsorption of ssDNA on the surfaces of MCNTs, and that for the latter is due to the strong electrostatic repulsion force between the negative charge TCPP/MCNTs complexes and dsDNA. Thus, target DNA in a DNA sample and single-base mismatch in DNA sequences could be easily detected.
Huang
Cheng Zhi
CZ
College of Pharmaceutical Sciences, CQKL-LRTA, Southwest University, Chongqing 400715, China. chengzhi@swu.edu.cn
Liao
Qie Gen
QG
Li
Yuan Fang
YF
D020137:Base Pair Mismatch; D004247:DNA / Q000032:analysis*; D015342:DNA Probes; D037742:Nanotubes, Carbon / Q000737:chemistry*; D055095:Optics and Photonics; D011166:Porphyrins / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence
D015342:DNA Probes; D037742:Nanotubes, Carbon; D011166:Porphyrins; C018395:tetracarboxyphenylporphine; D004247:DNA