A novel signal amplification strategy based on a Pb-dependent DNAzyme is proposed for detecting Pb and radon through Pb-induced DNAzyme cleavage and the auto-assembly of a duplex-hemin/G-quadruplex with two loop-stem structures and enzyme-mimicking catalytic activity. First, the Pb-specific DNAzyme cleaves a primer sequence, which induces assembly of the hairpin probe Hp1/Hp2 into a double helix structure. Subsequently, a G-quadruplex forms after the insertion of hemin into the free G-rich sequences; this G-quadruplex possesses the catalytic activity of horseradish peroxidase and changes colorless TMB to its deeply colored oxidized state. lead-dependent DNAzymes were constantly sheared by Pb, and the free primer strands were continuously assembled into double chains by hybridization with hairpin probes, providing amplification for the detection of lead (II) and radon. Under the optimum conditions, there was a good linear relationship between ΔA and the lead concentration for Pb concentrations ranging from 2.58 to 18 nM, and the detection limit was 0.77 nM. Analysis of actual samples indicated that when the radon concentration was in the range of 5.41 × 10 1.65 × 10 Bq·h/m, the radon concentration and the absorbance were linearly correlated with a detection limit of 1.62 × 10 Bq·h/m. During the process of radon sampling and detection, radiation damage from the radioactive gas radon can be avoided. In this study, the primer dissociated by the DNAzyme was in a free state. Compared with the fixed-state primer chain, this system will be more convenient for the biological analysis of ultratrace metal ions. Therefore, this strategy has good application prospects for biosensors and is expected to become a novel platform for the amplification and detection of metal ion signals.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.jpba.2018.07.026 | DOI Listing |
Can J Surg
January 2025
From the Faculty of Medicine, Dalhousie University, Halifax, N.S. (Huo); the Department of Primary Education, School of Education, University of Ioannina, Ioannina, Greece (Kontouli); the Department of Diagnostic Radiology, Dalhousie University, Halifax, N.S. (Manos); the Department of Pathology, Dalhousie University, Halifax, N.S. (Xu, Fris); the Department of Urology, Dalhousie University, Halifax, N.S. (Chun); the Division of Thoracic Surgery, Department of Surgery, Dalhousie University, Halifax, N.S. (Wallace, French)
Background: There is a need to expand eligibility criteria for lung cancer screening beyond age and smoking history. In this study, we sought to assess whether light-or-never-smokers and heavy smokers differ in molecular and immunologic markers based on conventional lung cancer screening criteria.
Methods: We conducted a retrospective review of lung cancer cases from 2005 to 2018 at a tertiary Canadian institution.
Sensors (Basel)
November 2024
Department of Environmental Health, Faculty of Health Sciences, Doornfontein Campus, University of Johannesburg, P.O. Box 524, Johannesburg 2006, South Africa.
This review aimed to explore advances in radon detection methods, emphasizing cost-effectiveness and accessible techniques such as CDs, DVDs, and glass-based detectors. In this review, we compared traditional methods like alpha track detectors and continuous radon monitors with emerging innovations that leverage polycarbonate material and IoT-integrated systems. Our evaluation of the synthesis suggests that CDs and DVDs provide scalable solutions for long-term radon monitoring, while glass-based detectors like CR-39 offer high sensitivity for epidemiological studies.
View Article and Find Full Text PDFJ Environ Radioact
January 2025
College of Physics and Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, Guangdong, China; Shenzhen Key Laboratory of Nuclear and Radiation Safety, Shenzhen, 518060, Guangdong, China.
Sci Rep
November 2024
Department of Environment, Land and Infrastructure Engineering (DIATI), Politecnico di Torino, Turin, Italy.
Zhongguo Ying Yong Sheng Li Xue Za Zhi
November 2024
PSIT-Pranveer Singh Institute of Technology (Pharmacy), Kalpi Road, Bhauti, Kanpur, India.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!