title: Silicon nanoparticles as a luminescent label to DNA.
abstract: We successfully conjugated 1-2 nm diameter silicon nanoparticles to a 5'-amino-modified oligonucleotide (60mer) that contains a C6 linker between amide and phosphate groups. The conjugation was implemented via two photoinduced reactions followed by a DNA labeling step through formation of a carboxamide bond. Photoluminescence of the conjugates is dominated by two blue bands (400 and 450 nm maximal) under 340 nm excitation. The quantum yield of oligonucleotide-conjugated nanoparticles was determined to be 0.08 as measured against quinine sulfate in 0.1 M HClO(4) as a reference standard. We report a conjugation process that allows labeling of Si nanoparticles to an oligonucleotide in aqueous solutions. Ways to further optimize the procedure in order to achieve narrower and brighter photoluminescence are discussed.
authors.affiliation: Biotechnology Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8312, USA. lili.wang@nist.gov
authors.forename: L
authors.initials: L
authors.lastname: Wang
authors.forename: V
authors.initials: V
authors.lastname: Reipa
authors.forename: J
authors.initials: J
authors.lastname: Blasic
mesh_terms: D004247:DNA / Q000737:chemistry / Q000378:metabolism*; D008163:Luminescent Measurements; D043942:Nanotubes / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry / Q000378:metabolism*
chemical_list: D004247:DNA; D012825:Silicon