title: Gold-nanoparticle-based colorimetric discrimination of cancer-related point mutations with picomolar sensitivity.
abstract: Point mutations in the Kirsten rat sarcoma viral oncogene homologue (KRAS) gene are being increasingly recognized as important diagnostic and prognostic markers in cancer. In this work, we describe a rapid and low-cost method for the naked-eye detection of cancer-related point mutations in KRAS based on gold nanoparticles. This simple colorimetric assay is sensitive (limit of detection in the low picomolar range), instrument-free, and employs nonstringent room temperature conditions due to a combination of DNA-conjugated gold nanoparticles, a probe design which exploits cooperative hybridization for increased binding affinity, and signal enhancement on the surface of magnetic beads. Additionally, the scheme is suitable for point-of-care applications, as it combines naked-eye detection, small sample volumes, and isothermal (PCR-free) amplification.
authors.affiliation: Center for Bio-Molecular Nanotechnologies@UniLe, Istituto Italiano di Tecnologia, Via Barsanti-73010 Arnesano (Lecce), Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Valentini
authors.forename: Roberto
authors.initials: R
authors.lastname: Fiammengo
authors.forename: Stefania
authors.initials: S
authors.lastname: Sabella
authors.forename: Manuela
authors.initials: M
authors.lastname: Gariboldi
authors.forename: Gabriele
authors.initials: G
authors.lastname: Maiorano
authors.forename: Roberto
authors.initials: R
authors.lastname: Cingolani
authors.forename: Pier Paolo
authors.initials: PP
authors.lastname: Pompa
mesh_terms: D001483:Base Sequence; D045744:Cell Line, Tumor; D003124:Colorimetry / Q000191:economics / Q000379:methods*; D003362:Cost-Benefit Analysis; D004265:DNA Helicases / Q000378:metabolism; D006046:Gold / Q000737:chemistry*; D006801:Humans; D053768:Metal Nanoparticles / Q000737:chemistry*; D008958:Models, Molecular; D009369:Neoplasms / Q000235:genetics*; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D015345:Oligonucleotide Probes / Q000737:chemistry / Q000235:genetics; D010316:Particle Size; D017354:Point Mutation; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics*
chemical_list: C117307:KRAS protein, human; D015345:Oligonucleotide Probes; D011518:Proto-Oncogene Proteins; D006046:Gold; D004265:DNA Helicases; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins