Chemosensors
·
2024
·Vol. 12
·期 6
·104
·
IF 3.7
Yanyan Xing,Pingping He,Deyong Wang,Yuan Liang,Xing Gao,Xiaohong Hou
Colorimetric biosensor-based nanozymes have received considerable attention in various fields thanks to the advantages of the simple preparation, good stability, and regulable catalytic activity of nanozymes. In this study, a bimetallic nanozyme Fe3O4@Co3O4/CN was prepared via the high-temperature calcination of Fe3O4-PVP@ZIF-67. The material retained its skeletal structure before calcination, which prevented the aggregation of nanoparticles and exposed more active sites of the nanozyme, substantially enhancing the intrinsic dual enzyme-mimetic activities, including peroxidase- and oxidase-like activities. In particular, Fe3O4@Co3O4/CN with oxidase-like activity catalyzed the colorless tetramethylbenzidine (TMB) to become blue oxTMB with oxygen. Reducing glutathione (GSH) could inhibit the above oxidation reaction. In contrast, with respect to the existence of mercury(II), GSH bound to mercury(II) due to the strong affinity between mercury(II) and -SH, thus eliminating the inhibition and restoring the oxTMB signal. A simple and effective colorimetric sensor was fabricated to detect mercury(II) based on the above principles. The proposed measurement had a linear range of 0.1–15 μM and a limit of detection (LOD) of 0.017 μM. It was shown that the established colorimetric sensing system could be successfully applied to detect mercury(II) in water samples, and the Fe3O4@Co3O4/CN nanozyme proved to be a promising candidate for biosensing application.
研究领域:
生物传感
·
材料科学
·
环境监测
✓ 已验证
产品关联
DOI
高影响因子
ANALYST
·
2021
·Vol. 146
·期 8
·2664-2669
·
IF 4.616
Liling Lu,Xiao Han,Jingwen Lin,Yingxin Zhang,Minghao Qiu,Ying Chen,Meijin Li,Dianping Tang
Herein a rapid and sensitive fluorometric bioanalysis platform for mercury(II) (Hg2+) detection was innovatively developed using ultrathin two-dimensional MXenes (Ti3C2) as fluorescence quencher and Hg2+-induced exonuclease III (Exo III)-assisted target recycling strategy for efficient signal amplification. Initially, fluorophore-labeled single-stranded DNA (FAM-labeled probe) can be easily adsorbed onto the surface of ultrathin Ti3C2 nanosheets by hydrogen bonding and metal chelating interaction, and the fluorescence signal emitted by the FAM-labeled probe is quenched strongly owing to the fluorescence resonance energy transfer between the FAM and ultrathin Ti3C2 nanosheets. Upon sensing the target Hg2+, the protruding DNA fragment at the 3′ end of hairpin will hybridize with primer (hairpin-Hg2+-primer), and then further digested by Exo III to produce a probe (nicker). The released target Hg2+ and primer continue to participate in the next recycling, resulting in more hairpin probes becoming nickers. The combination of a large number of nickers and FAM-probe resulted in a significant increase in the fluorescence signal of the system, which was attributed to the fact that the double helix DNA was more rigid and separated from the surface of the ultrathin Ti3C2 nanosheets. The obvious fluorescence signal change of the Ti3C2-based Exo III-assisted target recycling can be accurately monitored by fluorescence spectrometry, which is also proportional to the concentration of Hg2+. Under optimum operating conditions, the peak intensity (520 nm wavelength) of fluorescence increased with increasing Hg2+ within a wide dynamic working range from 0.05 nM to 50 nM (R2 = 0.9913) with a limit of detection down to 42.5 pM. The proposed strategy uses ultrathin MXenes as a platform for binding nucleic acids, which contributes to its potential in nucleic acid hybridization-based biosensing and/or nucleic acid signal amplification bio-applications.
研究领域:
分析化学
·
环境科学
·
纳米技术
·
生物传感
✓ 已验证
DOI
PubMed
高影响因子
Sensors and Actuators Reports
·
2024
·
IF 6.5
Duan Xiong,Zhen Su,Lixin Zhang,Hao Zhang,Zhiwei Su,Xiaoyun Hu,Mailidan Wumaer,Qingqing Guan
Manipulation of the one-dimensional (1D) supramolecular assembly of platinum(II) terpyridyl complex is promising for achieving precise onsite mercury(II) detection in complex environments, but still challenging. Herein, by systematic molecular design of platinum(II) terpyridyl complex, chloride-mediated 1D supramolecular assembly has been successfully achieved, exhibiting not only improved recognition ability but also dual-visual signal, with turn-on red luminescence and high-contrast color change from pale-yellow to orange-red. The probe also shows excellent selectivity and anti-interference properties, fast response rate (< 1 s) and low detection limit, stretching to 20.6 fg when incorporated in a hydrogel matrix. Structure insight for the dual-visual response shows that this high detection performance derives from the ancillary ligand of -NCS, which endows the increase of ion-association ability between platinum(II) terpyridyl complex and [HgCl 4 ] 2− , leading that 1D packing mode with strengthened Pt-Pt interactions. In all, this work highlights a new strategy of 1D supramolecular assembly construction for high performance detection of heavy metal ions.
研究领域:
分析化学
·
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2017
·
IF 5.401
Yilin Lu,Jie Zhong,Guohua Yao,Qing Huang
A prototype of label-free SERS sensor, based on the formation of T-Hg 2+ -T pairs and the corresponding orientation variation of DNA on Au shell surface, was developed for detection of Hg 2+ in aqueous solution quantitatively and selectively. The DNA aptamer immobilized on the surface of SiO 2 @Au core/shell nanoparticles (NPs) consisted of two segments, namely, the segment which has the consecutive thymines (T) severing as the Hg 2+ recognition elements, and the segment which contains the guanine (G) and adenine (A) bases working as the signal reporter. With interaction of Hg 2+ ions and the thymines between the adjacent single-stranded DNA (ssDNA), the DNA molecule adopted vertical orientation, resulting in increase of Raman intensity ratio I(660 cm −1 )/I(736 cm −1 ) with increase of Hg 2+ concentration, which thus allowed to measure trace amounts of Hg 2+ in aqueous solution selectively and quantitatively. Our results revealed that this label-free SERS sensor could sensitively respond to Hg 2+ ions within a wide concentration range (from 1 × 10 −8 to 1 × 10 −3 M). This work therefore demonstrates that proper design of aptamer-modified SiO 2 @Au core/shell NPs can be utilized for label-free SERS detection of heavy metal ions in the environment.
研究领域:
环境科学
·
分析化学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
MICROCHIMICA ACTA
·
2019
·Vol. 186
·期 2
·1-7
·
IF 5.479
Song Xiaolei,Wang Yu,Liu Su,Zhang Xue,Wang Haiwang,Wang Jingfeng,Huang Jiadong
A colorimetric biosensor and visual test is described for the determination of mercury(II). It relies on the specific thymine-Hg(II)-thymine (T-Hg 2+ -T) interaction which induces a cyclic amplification process (caused by the enzyme exonuclease III) and the aggregation of gold nanoparticles. These results in a color change from red to violet. Under optimized conditions, this colorimetric assay (best performed at 524 nm) has a detection limit as low as 0.9 nM with a detection range over 4 orders of magnitude (from 1 nM to 10 μM).
Schematic of a colorimetric method for determination of mercury ions (Hg 2+ ) based on the thymine-Hg 2+ -thymine interaction-triggered cyclic enzymatic amplification and aggregation of gold nanoparticles with the aid of exonuclease III (Exo III).
研究领域:
分析化学
·
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）