title: Electrochemical biosensor for the detection of cauliflower mosaic virus 35 S gene sequences using lead sulfide nanoparticles as oligonucleotide labels.
abstract: Lead sulfide (PbS) nanoparticles were synthesized in aqueous solution and used as oligonucleotide labels for electrochemical detection of the 35 S promoter from cauliflower mosaic virus (CaMV) sequence. The PbS nanoparticles were modified with mercaptoacetic acid and could easily be linked with CaMV 35 S oligonucleotide probe. Target DNA sequences were covalently linked on a mercaptoacetic acid self-assembled gold electrode, and DNA hybridization of target DNA with probe DNA was completed on the electrode surface. PbS nanoparticles anchored on the hybrids were dissolved in the solution by oxidation of HNO3 and detected using a sensitive differential pulse anodic stripping voltammetric method. The detection results can be used to monitor the hybridization reaction. The CaMV 35 S target sequence was satisfactorily detected with the detection limit as 4.38 x 10(-12)mol/L (3sigma). The established method extends nanoparticle-labeled electrochemical DNA analysis to specific sequences from genetically modified organisms with higher sensitivity and selectivity.
authors.affiliation: College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, Shandong, China. sunwei@qust.edu.cn
authors.forename: Wei
authors.initials: W
authors.lastname: Sun
authors.forename: Jianghua
authors.initials: J
authors.lastname: Zhong
authors.forename: Peng
authors.initials: P
authors.lastname: Qin
authors.forename: Kui
authors.initials: K
authors.lastname: Jiao
mesh_terms: D020137:Base Pair Mismatch; D001483:Base Sequence; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D017796:Caulimovirus / Q000235:genetics*; D004563:Electrochemistry; D004566:Electrodes; D005814:Genes, Viral / Q000235:genetics*; D007854:Lead / Q000737:chemistry* / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry*; D009841:Oligonucleotides / Q000032:analysis* / Q000235:genetics* / Q000378:metabolism; D012680:Sensitivity and Specificity; D013194:Staining and Labeling; D013440:Sulfides / Q000737:chemistry* / Q000378:metabolism
chemical_list: D009841:Oligonucleotides; D013440:Sulfides; C018391:lead sulfide; D007854:Lead