title: Introduction of hematoxylin as an electroactive label for DNA biosensors and its employment in detection of target DNA sequence and single-base mismatch in human papilloma virus corresponding to oligonucleotide.
abstract: For the detection of DNA hybridization, a new electrochemical biosensor was developed on the basis of the interaction of hematoxylin with 20-mer deoxyoligonucleotides (from human papilloma virus, HPV). The study was performed based on the interaction of hematoxylin with an alkanethiol DNA probe self-assembled gold electrode (ss-DNA/AuE) and its hybridization form (ds-DNA/AuE). The optimum conditions were found for the immobilization of HPV probe on the gold electrode (AuE) surface and its hybridization with the target DNA. Electrochemical detection of the self-assembled DNA and the hybridization process were performed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) over the potential range where the accumulated hematoxylin at the modified electrode was electroactive. Observing a remarkable difference between the voltammetric signals of the hematoxylin obtained from different hybridization samples (non-complementary, mismatch and complementary DNAs), we confirmed the potential of the developed biosensor in detecting and discriminating the target complementary DNA from non-complementary and mismatch oligonucleotides. Under optimum conditions, the electrochemical signal had a linear relationship with the concentration of the target DNA ranging from 12.5 nM to 350.0 nM, and the detection limit was 3.8 nM.
authors.affiliation: Department of Chemistry, Yazd University, P.O. Box 89195-741, Yazd, Iran.
authors.forename: Navid
authors.initials: N
authors.lastname: Nasirizadeh
authors.forename: Hamid R
authors.initials: HR
authors.lastname: Zare
authors.forename: Mohammad Hossein
authors.initials: MH
authors.lastname: Pournaghi-Azar
authors.forename: Mohammad Saeid
authors.initials: MS
authors.lastname: Hejazi
mesh_terms: D020137:Base Pair Mismatch / Q000235:genetics*; D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D015344:DNA Probes, HPV / Q000235:genetics*; D004279:DNA, Viral / Q000032:analysis / Q000737:chemistry / Q000235:genetics*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D018390:Gene Targeting / Q000295:instrumentation; D006416:Hematoxylin / Q000032:analysis / Q000737:chemistry*; D017403:In Situ Hybridization / Q000295:instrumentation; D017422:Sequence Analysis, DNA / Q000295:instrumentation*; D013194:Staining and Labeling / Q000379:methods
chemical_list: D015344:DNA Probes, HPV; D004279:DNA, Viral; D006416:Hematoxylin