Direct visual detection of DNA based on the light scattering of silica nanoparticles on a human papillomavirus DNA chip.
A detection system for a human papillomavirus (HPV) DNA chip based on the light scattering of aggregated silica nanoparticle probes is presented. In the assay, a target HPV DNA is sandwiched between the capture DNA immobilized on the chip and the probe DNA immobilized on the plain silica nanoparticle. The spot where the sandwich reaction occurs appears bright white and is readily distinguishable to the naked eye. Scanning electron microscopy images clearly show the aggregation of the silica nanoparticle probes. When three different sized (55 nm, 137 nm, 286 nm) plain silica nanoparticles were compared, probes of the larger silica nanoparticles showed a higher scattering intensity. Using 286-nm silica nanoparticles, the spots obtained with 200 pM of target DNA were visually detectable. The demonstrated capability to detect a disease related target DNA with direct visualization without using a complex detection instrument provides the prerequisite for the development of portable testing kits for genotyping.
Piao
Jing Yu
JY
Department of Chemistry, Seoul National University, Seoul, Republic of Korea.
Park
Eun Hee
EH
Choi
Kihwan
K
Quan
Bo
B
Kang
Dong Ho
DH
Park
Pan Yun
PY
Kim
Dai Sik
DS
Chung
Doo Soo
DS
D004279:DNA, Viral / Q000032:analysis* / Q000235:genetics; D005838:Genotype; D006801:Humans; D008027:Light; D008855:Microscopy, Electron, Scanning; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation / Q000379:methods*; D027383:Papillomaviridae / Q000235:genetics*; D030361:Papillomavirus Infections / Q000175:diagnosis / Q000821:virology; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry*
D004279:DNA, Viral; D012822:Silicon Dioxide