Microflow injection potassium bioassay based on G‐quadruplex DNAzyme‐enhanced chemiluminescence. (23rd May 2014)

• Record Type: Journal Article
• Authors: Song, Lifang; Pan, Xiaoyan; Shen, Hong; Yu, Yaling
• Is Part Of: Luminescence. Volume 29:Number 8(2014)
• Page Start: 1066
• Page End: 1073
• Publication Date: 2014-05-23
• Subjects: Luminescence -- Periodicals; Bioluminescence -- Periodicals; Chemiluminescence -- Periodicals; Luminescence -- Periodicals; 535.35
• DOI: 10.1002/bio.2661
• Languages: English
• ISSNs: 1522-7235

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>By taking advantage of microflow injection chemiluminescence analysis, we developed a distinctive microfluidic bioassay method based on G‐Quadruplex DNAzyme‐enhanced chemiluminescence for the determination of K⁺ in human serum. AGRO100, the G‐rich oligonucleotide with high hemin binding affinity was primarily selected as a K⁺ recognition element. In the presence of K⁺, AGRO100 folded into G‐quadruplex and bound hemin to form DNAzyme, which catalyzed the oxidation of luminol by H₂O₂ to produce chemiluminescence. The intensity of chemiluminescence increased with the K⁺ concentration. In the study, the DNAzyme showed both long‐term stability and high catalytic activity; other common cations at their physiological concentration did not cause notable interference. With only 6.7 × 10⁻¹³ mol of AGRO100 consumption per sample, a linear response of K⁺ ranged from 1 to 300 µmol/L, the concentration detection limit 0.69 µmol/L (S/N = 3) and the absolute detection limit 1.38 × 10⁻¹² mol were obtained. The precision of 10 replicate measurements of 60 µmol/L K⁺ was found to be 1.72% (relative standard deviation). The accuracy of the method was demonstrated by analyzing real human serum samples. Copyright © 2014 John Wiley &amp; Sons, Ltd.</p> </abstract>