title: Non-cross-linking gold nanoparticle aggregation as a detection method for single-base substitutions.
abstract: Aggregation of DNA-modified gold nanoparticles in a non-cross-linking configuration has extraordinary selectivity against terminal mismatch of the surface-bound duplex. In this paper, we demonstrate the utility of this selectivity for detection of single-base substitutions. The samples were prepared through standard protocols: DNA extraction, PCR amplification and single-base primer extension. Oligonucleotide-modified nanoparticles correctly responded to the unpurified products from the primer extension: aggregation for the full match and dispersion for all the mismatches. Applicability of this method to genomic DNA was tested with five human tumor cell lines, and verified by conventional technologies: mass spectrometry and direct sequencing. Unlike the existing methods for single-base substitution analysis, this method does not need specialized equipments, and opens up a new possibility of point-of-care diagnosis for single-nucleotide polymorphisms.
authors.affiliation: Bioengineering Laboratory, RIKEN (The Institute of Physical and Chemical Research) Hirosawa 2-1, Wako, Saitama 351-0198, Japan.
authors.forename: Kae
authors.initials: K
authors.lastname: Sato
authors.forename: Kazuo
authors.initials: K
authors.lastname: Hosokawa
authors.forename: Mizuo
authors.initials: M
authors.lastname: Maeda
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D045744:Cell Line, Tumor; D003124:Colorimetry; D006046:Gold / Q000737:chemistry*; D006801:Humans; D049329:Nanostructures; D009693:Nucleic Acid Hybridization / Q000379:methods*; D017354:Point Mutation; D020641:Polymorphism, Single Nucleotide; D017422:Sequence Analysis, DNA / Q000379:methods*
chemical_list: D006046:Gold