Peptide nucleic acid as a selective recognition element for electrochemical determination of Hg 2+
Agnieszka Bala , Łukasz Górski
AbstractA novel electrochemical PNA-based biosensor for the determination of Hg2+ is described. The receptor layer, containing single strands of polythymine PNA (peptide nucleic acid),was formed at the surface of gold electrode. Due to the presence of thymine bases and peptide bonds, an interaction between Hg2+ ion and receptor layer occurs. The influence of chainmodification – PNA vs. DNA – and type of redoxmarker – anionic AQMS-Na (sodiumsalt of anthraquinone-2-sulfonic acid) and FeII/III (potassium ferri/ferrocyanide) or cationic MB (methylene blue) and RuHex (hexaammineruthenium(III) chloride) – were studied. Proposed PNA-based biosensor with anionic AQMS-Na as a redoxmarker demonstrated significantly better analytical parameters, as compared to results obtained for other tested redox markers (for measurements at pH 6.0). The linear response towards Hg2+ was in the range from 5 to 500 nmol·L−1 with the detection limit of 4.5 nmol·L−1. The developed sensor distinguishes itself with high selectivity towards Hg2+, even for solutions containing several interfering cations. Interactions between Hg2+ and PNA receptor layerwere studied using squarewave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS).
|Journal series||Bioelectrochemistry, ISSN 1567-5394, (A 35 pkt)|
|Publication size in sheets||0.5|
|Keywords in English||PNA sensor; thymine bases; electrochemical technique; mercury ion; redox marker|
|Score|| = 35.0, 06-08-2018, ArticleFromJournal|
= 35.0, 06-08-2018, ArticleFromJournal
|Publication indicators||: 2016 = 3.346 (2) - 2016=3.413 (5)|
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or Perish system.