Toward an ICPMS-linked DNA assay based on gold nanoparticles immunoconnected through peptide sequences.
Gold nanoparticles modified with anti-mouse IgG have been used to trace oligonucleotides carrying a c-myc peptide. Two strategies, a dot-blot format as well as inductively coupled plasma mass spectrometry (ICPMS) have been used to detect the nanoparticle tracer. For both cases, oligonucleotide-peptide conjugates were first applied to a nitrocellulose membrane using a manifold attached to a suction device. After immobilization of the oligonucleotide by UV radiation, the samples were incubated with an anti-c-myc monoclonal antibody. In the case of the dot-blot format strategy, it was followed by incubation with a secondary antibody conjugated to horseradish peroxidase and development with luminol as chemiluminescent substrate. In the case of ICPMS strategy, it was followed by incubation with the secondary antibody (anti-mouse IgG) conjugated to gold nanoparticles and their ICPMS detection after dissolving. The nonspecific adsorptions were found to be around zero. The limit of detection for peptide-modified DNA was 0.2 pmol. The method may have significant potential as an important ICPMS-based nonradioactive DNA detection method for the simultaneous determination of various sequences by labeling different kinds of inorganic nanoparticles.
Merkoçi
Arben
A
Grup de Sensors i Biosensors, Departament de Química, Universitat Autonoma de Barcelona, 08193 Bellaterra, Spain. arben.merkoci@uab.es
Aldavert
Marta
M
Tarrasón
Gemma
G
Eritja
Ramon
R
Alegret
Salvador
S
D004247:DNA / Q000032:analysis* / Q000737:chemistry*; D006046:Gold / Q000032:analysis / Q000737:chemistry*; D007118:Immunoassay; D013058:Mass Spectrometry / Q000379:methods*; D053758:Nanoparticles / Q000032:analysis* / Q000737:chemistry*; D009841:Oligonucleotides / Q000032:analysis / Q000737:chemistry; D010455:Peptides / Q000737:chemistry*
D009841:Oligonucleotides; D010455:Peptides; D006046:Gold; D004247:DNA