title: Electrochemical uranyl cation biosensor with DNA oligonucleotides as receptor layer.
abstract: The present study aims at the further development of the uranyl oligonucleotide-based voltammetric biosensor, which takes advantage of strong interaction between UO2(2+) and phosphate DNA backbone. Herein we report the optimization of working parameters of previously elaborated electrochemical DNA biosensor. It is shown that the sensor sensitivity is highly dependent on the oligonucleotide probe length and the incubation time of sensor in a sample solution. Consequently, the highest sensitivity was obtained for 10-nucleotide sequence and 60 min incubation time. The lower detection limit towards uranyl cation for developed biosensor was 30 nM. The influence of mixed monolayers and the possibility of developing a non-calibration device were also investigated. The selectivity of the proposed biosensor was significantly improved via elimination of adenine nucleobases from the DNA probe. Moreover, the regeneration procedure was elaborated and tested to prolong the use of the same biosensor for 4 subsequent determinations of UO2(2+).
authors: Institute of Biotechnology, Department of Microbioanalytics, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
authors: Marta
authors: M
authors: Jarczewska
authors: Institute of Biotechnology, Department of Microbioanalytics, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
authors: Robert
authors: R
authors: Ziółkowski
authors: Institute of Biotechnology, Department of Microbioanalytics, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland. Electronic address: lukegor@ch.pw.edu.pl.
authors: Łukasz
authors: Ł
authors: Górski
authors: Institute of Biotechnology, Department of Microbioanalytics, Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland.
authors: Elżbieta
authors: E
authors: Malinowska
mesh_terms: D001483:Base Sequence; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D015342:DNA Probes / Q000737:chemistry* / Q000235:genetics; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004566:Electrodes; D017743:Equipment Reuse; D015345:Oligonucleotide Probes / Q000737:chemistry* / Q000235:genetics; D017974:Uranium Compounds / Q000032:analysis* / Q000737:chemistry*
chemical_list: D015342:DNA Probes; D015345:Oligonucleotide Probes; D017974:Uranium Compounds; C012597:uranium dioxide
keywords: DNA biosensor; Electrochemical biosensor; Metals determination; Mixed monolayer; Uranyl cation