title: Low-cost and highly efficient DNA biosensor for heavy metal ion using specific DNAzyme-modified microplate and portable glucometer-based detection mode.
abstract: A simple and low-cost DNA sensing platform based on Pb(2+)-specific DNAzyme-modified microplate was successfully developed for highly sensitive monitoring of lead ion (Pb(2+), one kind of toxic heavy metal ion) in the environmental samples coupling with a portable personal glucometer (PGM)-based detection mode. The detection cell was first prepared simply by means of immobilizing the DNAzyme on the streptavidin-modified microplate. Gold nanoparticle labeled with single-stranded DNA and invertase (Enz-AuNP-DNA) was utilized as the signal-transduction tag to produce PGM substrate (glucose). Upon addition of lead ion into the microplate, the substrate strand of the immobilized DNAzyme was catalytically cleaved by target Pb(2+), and the newly generated single-strand DNA in the microplate could hybridize again with the single-stranded DNA on the Enz-AuNP-DNA. Accompanying with the Enz-AuNP-DNA, the carried invertase could convert sucrose into glucose. The as-produced glucose could be monitored by using a widely accessible PGM for in situ amplified digital readout. Based on Enz-AuNP-DNA amplification strategy, as low as 1.0 pM Pb(2+) could be detected under the optimal conditions. Moreover, the methodology also showed good reproducibility and high selectivity toward target Pb(2+) against other metal ions because of highly specific Pb(2+)-dependent DNAzyme, and was applicable for monitoring Pb(2+) in the naturally contaminated sewage and spiked drinking water samples.
authors.affiliation: Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, Chongqing University of Arts and Sciences, Chongqing 402160, PR China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, Chongqing University of Arts and Sciences, Chongqing 402160, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, Chongqing University of Arts and Sciences, Chongqing 402160, PR China.
authors.forename: Liumei
authors.initials: L
authors.lastname: Teng
authors.affiliation: Institute of Environmental and Analytical Science, School of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, Henan, PR China. Electronic address: minghua.luhnu@gmail.com.
authors.forename: Minghua
authors.initials: M
authors.lastname: Lu
authors.affiliation: Chongqing Key Laboratory of Environmental Materials & Remediation Technologies, Chongqing University of Arts and Sciences, Chongqing 402160, PR China; Institute of Nanomedicine and Nanobiosensing, Department of Chemistry, Fuzhou University, Fuzhou 350108, PR China. Electronic address: dianping.tang@fzu.edu.cn.
authors.forename: Dianping
authors.initials: D
authors.lastname: Tang
mesh_terms: D015374:Biosensing Techniques; D015190:Blood Glucose Self-Monitoring; D021881:DNA, Catalytic / Q000737:chemistry; D004277:DNA, Single-Stranded / Q000737:chemistry*; D004784:Environmental Monitoring; D006046:Gold / Q000737:chemistry; D007477:Ions / Q000737:chemistry / Q000302:isolation & purification*; D007854:Lead / Q000737:chemistry / Q000302:isolation & purification*; D053768:Metal Nanoparticles; D009693:Nucleic Acid Hybridization
chemical_list: D021881:DNA, Catalytic; D004277:DNA, Single-Stranded; D007477:Ions; D007854:Lead; D006046:Gold
keywords: Gold nanoparticle label; Invertase; Lead ion sensor; Pb(2+)-specific DNAzyme; Portable personal glucometer