Department of Chemistry
DNA hybridization of pathogenicity island of vancomycin-resistant Enterococcus faecalis with discretely functionalized gold nanoparticles in organic solvent mixtures
Short single-strand (ss) DNA sensors that involve mono-functionalized gold nanoparticles are reported for the first time. By way of an example, the hybridization and detection of a 10 base-pair oligonucleotide (TGACTCTTAA), which relates to the pathogenicity island of vancomycin-resistant Enterococcus faecalis, has been demonstrated in the organic solvent mixture (DMF/CHCl 3/H 2O/NaCl) at sub-nanomole concentrations. The formation of the resulting double-strand (ds) DNA-AuNP complexes which involve either tail-to-tail or head-to-head alignment, are sensitive to salt (NaCl) and solvent (CHCl 3) concentrations. By UV/visible absorption measurements, it has been found that the melting temperature of the dsDNA-AuNP complexes increases with increasing salt concentrations as well as the chloroform ratio, for both tail-to-tail and head-to-head alignments. Transmission electron microscopic images of the dsDNA-AuNP complexes with mono-functionalized AuNPs reveal significant amounts of dimeric AuNP species while that of randomly functionalized AuNPs reveal an agglomerated AuNP nanostructures. © 2011 The Royal Society of Chemistry.
Source Publication Title
Royal Society of Chemistry
Chak, Chun-Pong, Josie M. Y. Lai, Kathy W. Y. Sham, Christopher H. K. Cheng, and Ken Cham-Fai Leung. "DNA hybridization of pathogenicity island of vancomycin-resistant Enterococcus faecalis with discretely functionalized gold nanoparticles in organic solvent mixtures." RSC Advances 1.7 (2011): 1342-1348.