Highly sensitive and selective detection of Pb²⁺ions using a novel and simple DNAzyme-based quartz crystal microbalance with dissipation biosensor

Abstract

A novel, label-free DNAzyme-based quartz crystal microbalance with dissipation monitoring (QCM-D) biosensor was developed for the highly sensitive and specific detection of Pb(2+) ions. To enhance the performance of the sensor, oligonucleotide-functionalized gold nanoparticles were used for both frequency and dissipation amplification. This sensor was developed by immobilizing Pb(2+)-specific DNAzymes onto the QCM-D sensor surface and allowing them to hybridize with substrate-functionalized AuNPs. The DNAzyme catalyzed the cleavage of the substrate in the presence of Pb(2+) ions, causing the cleaved substrate-functionalized AuNPs to be removed from the sensor surface. Thus, Pb(2+) ions can be determined on-line by monitoring the change in frequency and dissipation signals. The results revealed that the sensor showed a sensitive response to Pb(2+) ions with detection limits of 14 nM and 20 nM for frequency and dissipation, respectively. This QCM-D biosensor also exhibited excellent selectivity toward Pb(2+) ions in the presence of other divalent metal ions. In addition, the approach was able to detect Pb(2+) in tap water, demonstrating its great potential for monitoring drinking water quality. The proposed sensor system described here represents a new class of lead ion sensor. Its simple detection strategy makes it feasible for 'pollution-free' detection; thus, the approach could have applications in on-line water quality monitoring.

Glutathione-capped Syzygium cumini carbon dot-amalgamated agarose hydrogel film for naked-eye detection of heavy metal ions

“…6 Calibration graph plotted between the color intensities of hydrogel films and different concentrations of a Pb 2+ ion in the range of 0.005-0.075 mM, b Fe 3+ ion in the range of 0.0075-0.1 mM, and c Mn 2+ ion in the range of 0.0075-0.1 mM without the aid of sophisticated instruments, which avoids tedious sample preparations. As shown in Table 1, GSH CD-agarose hydrogel film as a probe was compared with gold (Au) interdigitated electrodes, Au nanoparticles (Au NPs), AT-cut Au-coated quartz crystal, graphene quantum dots (GQDs) and Au NPs, L-tyrosine silver NPs (Ag NPs), and poly-L-α-glutamic acid (PGA) for Pb 2+ ion (Cui et al 2016;Teh et al 2014;Niu et al 2018;Annadhasan et al 2014;Hu and Elioff 2018). For Fe 3+ ion, various fluorometric methods were based on GQDs, sulphur-doped carbon dots (C-dots) and carbon quantum dots (CQDs), cranberry CDs, citric acid and (NH 4 ) 2 HPO 4 CDs, and alginic acid (AA) and ethane diamine (EDA) CDs (Zhang et al 2019;Xu et al 2015;Wu et al 2018;Zulfajri et al 2019;Chandra et al 2016;Liu et al 2015).…”

Construction of a sensitive and specific lead biosensor using a genetically engineered bacterial system with a luciferase gene reporter

“…At low concentration of heavy bioavailable metals, bioluminescence signals are likely to be suitable [19,20]. They can also be applied to monitoring bioavailable concentrations of heavy metal [21][22][23][24][25][26][27] and piezoelectric biosensors [28][29][30] as enzymebased electrochemical biosensors. One of the most obvious advantages of this method is the ability to measure the bioavailable heavy metal at very low concentrations.…”

Recent Advances of Electrospun Nanofibrous Membranes in the Development of Chemosensors for Heavy Metal Detection

“…Nevertheless, to the best of our knowledge, the development and application of ENM‐immobilized chemosensors/receptors for fast detection of analytes, especially heavy metal ions, have not been systematically reviewed. Some typical 1D, 2D, 3D, and mixed nanomaterials used for fabricating the chemosensors to detect heavy metals are summarized in Table 1 . Compared with other nanomaterials, ENMs have obvious advantages and disadvantages.…”