title: Ultrasensitive indicator-free and enhanced self-signal nanohybrid DNA sensing platform based on electrochemically grown poly-xanthurenic acid/Fe2O3 membranes.
abstract: This paper describes a novel electrochemical DNA biosensor for simple, rapid, and specific detection of PML/RARA fusion gene in acute promyelocytic leukemia by using 18-mer single-stranded deoxyribonucleic acid as the capture probe. Nanosized Fe(2)O(3) was first immobilized on the surface of a carbon paste electrode (CPE). Then poly-xanthurenic acid (PXa), a new electroactive material, was electrogenerated by using the pulse potentiostatic method on the Fe(2)O(3) substrate to form a unique and uniform nanorhombus structure. Due to the unique binding ability of xanthurenic acid (Xa) with Fe(2)O(3), Xa monomers tended to be adsorbed around nanosized Fe(2)O(3), and the electropolymerization efficiency was greatly improved. Owing to the presence of abundant carboxyl groups, the capture probe was covalently attached on the carboxyl-terminated PXa/Fe(2)O(3) nanorhombus membranes through the free amines of DNA sequences based on the 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydrosulfosuccinimide cross-linking reaction. The covalently immobilized capture probe could selectively hybridize with its target DNA to form double-stranded DNA on the PXa/Fe(2)O(3)/CPE surface. Electrochemical impedance spectroscopy was adopted for indicator-free monitoring of the hybridization reaction on the probe-captured electrode. As a result, the efficient probe immobilization platform, coupled with the ultrasensitive indicator-free impedance measurement, gave rise to a detection limit of 2.8 fmol/L and a dynamic range spanning 8 orders of magnitude. The excellent analytical properties of the proposed biosensor developed here holds great promise for ultrasensitive detection of other biorecognition events and diagnosis of diseases in practice.
authors: State Key Laboratory Base of Eco-chemical Engineering, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, China.
authors: Wei
authors: W
authors: Zhang
authors: Tao
authors: T
authors: Yang
authors: Kui
authors: K
authors: Jiao
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation; D004252:DNA Mutational Analysis / Q000295:instrumentation; D004273:DNA, Neoplasm / Q000032:analysis / Q000235:genetics*; D004595:Electroplating / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005290:Ferric Compounds / Q000737:chemistry*; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute / Q000175:diagnosis* / Q000235:genetics; D008567:Membranes, Artificial; D036103:Nanotechnology / Q000295:instrumentation; D009687:Nuclear Proteins / Q000032:analysis / Q000235:genetics*; D000071156:Promyelocytic Leukemia Protein; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000295:instrumentation*; D014157:Transcription Factors / Q000032:analysis / Q000235:genetics*; D025521:Tumor Suppressor Proteins / Q000032:analysis / Q000235:genetics*; D014977:Xanthurenates / Q000737:chemistry
chemical_list: D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D005290:Ferric Compounds; D008567:Membranes, Artificial; D009687:Nuclear Proteins; D000071156:Promyelocytic Leukemia Protein; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; D014977:Xanthurenates; C070576:PML protein, human; C000499:ferric oxide; C028330:xanthurenic acid