title: Enzyme-amplified electrochemical biosensor for detection of PML-RARα fusion gene based on hairpin LNA probe.
abstract: In this study, an enzyme-amplified electrochemical biosensor was developed for detection of the promyelocytic leukemia/retinoic acid receptor alpha (PML/RARα) fusion gene in acute promyelocytic leukemia (APL). This new sensor employs a hairpin locked nucleic acids (LNAs) probe dually labeled with biotin and carboxyfluorescein molecule (FAM). The probe is immobilized at a streptavidin-modified electrode surface via the biotin-streptavidin bridge, and FAM serves as an affinity tag for the peroxidase conjugate binding. Initially, the immobilized hairpin probe was in the "closed" state in the absence of the target, which shielded FAM from being approached by the bulky anti-FAM-HRP conjugate due to the steric effect. Target binding opens the hairpin structure of the probe, the probe undergoes a significant conformational change, forcing FAM away from the electrode. As a result, the FAM label becomes accessible by the anti-FAM-HRP, and the target hybridization event can be sensitively transduced via the enzymatically amplified electrochemical current signal. This new biosensor demonstrates its excellent specificity for single-base mismatch and able to detect as little as 83 fM target DNA even in the presence of human serum. We also employed this sensor to directly detect PCR real sample with satisfactory results.
authors.affiliation: Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou 350004, China.
authors.forename: Liqing
authors.initials: L
authors.lastname: Lin
authors.forename: Qicai
authors.initials: Q
authors.lastname: Liu
authors.forename: Liman
authors.initials: L
authors.lastname: Wang
authors.forename: Ailin
authors.initials: A
authors.lastname: Liu
authors.forename: Shaohuang
authors.initials: S
authors.lastname: Weng
authors.forename: Yun
authors.initials: Y
authors.lastname: Lei
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.forename: Xinhua
authors.initials: X
authors.lastname: Lin
authors.forename: Yuanzhong
authors.initials: Y
authors.lastname: Chen
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D015342:DNA Probes; D055664:Electrochemical Techniques / Q000379:methods*; D006801:Humans; D015473:Leukemia, Promyelocytic, Acute / Q000175:diagnosis*; D009841:Oligonucleotides / Q000737:chemistry*; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013053:Spectrophotometry; D019809:Streptavidin / Q000737:chemistry
chemical_list: D015342:DNA Probes; D009841:Oligonucleotides; D015514:Oncogene Proteins, Fusion; C477371:locked nucleic acid; C093476:promyelocytic leukemia-retinoic acid receptor alpha fusion oncoprotein; D019809:Streptavidin