Single-Atomic Iron Doped Carbon Dots with Both Photoluminescence and Oxidase-Like Activity.

Multifunctional nanozymes can benefit biochemical analysis via expanding sensing modes and enhancing analytical performance, but designing multifunctional nanozymes to realize the desired sensing of targets is challenging. In this work, single-atomic iron doped carbon dots (SA Fe-CDs) are designed and synthesized via a facile in situ pyrolysis process. The small-sized CDs not only maintain their tunable fluorescence, but also serve as a support for loading dispersed active sites. Monoatomic Fe offers SA Fe-CDs exceptional oxidase-mimetic activity to catalyze 3,3',5,5'-tetramethylbenzidine (TMB) oxidation with fast response (Vmax  = 10.4 nM s-1 ) and strong affinity (Km  = 168 µM). Meanwhile, their photoluminescence is quenched by the oxidation product of TMB due to inner filter effect. Phosphate ions (Pi) can suppress the oxidase-mimicking activity and restore the photoluminescence of SA Fe-CDs by interacting with Fe active sites. Based on this principle, a dual-mode colorimetric and fluorescence assay of Pi with high sensitivity, selectivity, and rapid response is established. This work paves a path to develop multifunctional enzyme-like catalysts, and offers a simple but efficient dual-mode method for phosphate monitoring, which will inspire the exploration of multi-mode sensing strategies based on nanozyme catalysis.

[1]  T. Saleh.  Global trends in technologies and nanomaterials for removal of sulfur organic compounds: Clean energy and green environment , 2022, Journal of Molecular Liquids.

[2]  T. Saleh,et al.  Developing water treatment technologies in removing heavy metals from wastewater: A review , 2021, Environmental Nanotechnology, Monitoring & Management.

[3]  Hengjia Zhu,et al.  Realizing selective detection with nanozymes: Strategies and trends , 2021, TrAC Trends in Analytical Chemistry.

[4]  Javier Lou Franco,et al.  Nanozymes in Point-of-Care Diagnosis: An Emerging Futuristic Approach for Biosensing , 2021, Nano-micro letters.

[5]  T. Saleh.  Protocols for synthesis of nanomaterials, polymers, and green materials as adsorbents for water treatment technologies , 2021 .

[6]  D. Cui,et al.  A Review on Metal- and Metal Oxide-Based Nanozymes: Properties, Mechanisms, and Applications , 2021, Nano-micro letters.

[7]  Yuehe Lin,et al.  Recent progress on single-atom catalysts for CO2 electroreduction , 2021 .

[8]  Yuehe Lin,et al.  Single-Atomic Site Catalyst with Heme Enzymes-Like Active Sites for Electrochemical Sensing of Hydrogen Peroxide. , 2021, Small.

[9]  Yuehe Lin,et al.  Insights on forming N,O-coordinated Cu single-atom catalysts for electrochemical reduction CO2 to methane , 2021, Nature Communications.

[10]  M. Engelhard,et al.  An Ion-Imprinting Derived Strategy to Synthesize Single-Atom Iron Electrocatalysts for Oxygen Reduction. , 2020, Small.

[11]  T. Saleh.  Nanomaterials: Classification, properties, and environmental toxicities , 2020 .

[12]  F. Dai,et al.  Single-Atom Cobalt-Based Electrochemical Biomimetic Uric Acid Sensor with Wide Linear Range and Ultralow Detection Limit , 2020, Nano-Micro Letters.

[13]  C. Elliott,et al.  Gold Nanozymes: From Concept to Biomedical Applications , 2020, Nano-Micro Letters.

[14]  Yuehe Lin,et al.  High-performance dual-channel ratiometric colorimetric sensing of phosphate ion based on target-induced differential oxidase-like activity changes of Ce-Zr bimetal-organic frameworks , 2020 .

[15]  Chengzhou Zhu,et al.  Tuning Atomically Dispersed Fe Sites in Metal–Organic Frameworks Boosts Peroxidase-Like Activity for Sensitive Biosensing , 2020, Nano-micro letters.

[16]  Peng Liu,et al.  Smartphone-assisted off─on photometric determination of phosphate ion based on target-promoted peroxidase-mimetic activity of porous CexZr1-xO2 (x≥0.5) nanocomposites. , 2020, Environmental research.

[17]  Sundaram Gunasekaran,et al.  Nanozymes-based biosensors for food quality and safety , 2020 .

[18]  Yuming Huang,et al.  Size-controllable Fe-N/C single-atom nanozyme with exceptional oxidase-like activity for sensitive detection of alkaline phosphatase , 2020 .

[19]  Chengzhou Zhu,et al.  When Nanozymes Meet Single-Atom Catalysis. , 2019, Angewandte Chemie.

[20]  Chenghui Zhang,et al.  Gold nanoclusters-based dual-channel assay for colorimetric and turn-on fluorescent sensing of alkaline phosphatase , 2019 .

[21]  T. Saleh,et al.  Recent Advances in Functionalized Carbon Dots toward the Design of Efficient Materials for Sensing and Catalysis Applications. , 2019, Small.

[22]  Jingxiang Zhao,et al.  Revealing the Intrinsic Peroxidase-Like Catalytic Mechanism of Heterogeneous Single-Atom Co–MoS2 , 2019, Nano-Micro Letters.

[23]  Yuehe Lin,et al.  Single-Atom Nanozyme Based on Nanoengineered Fe-N-C Catalyst with Superior Peroxidase-Like Activity for Ultrasensitive Bioassays. , 2019, Small.

[24]  Xin Li,et al.  Highly sensitive and specific colorimetric detection of phosphate by using Zr(Ⅳ) to synergistically suppress the peroxidase-mimicking activity of hydrophilic Fe3O4 nanocubes , 2019, Sensors and Actuators B: Chemical.

[25]  Yuehe Lin,et al.  Unprecedented peroxidase-mimicking activity of single-atom nanozyme with atomically dispersed Fe-Nx moieties hosted by MOF derived porous carbon. , 2019, Biosensors & bioelectronics.

[26]  O. Chailapakul,et al.  Colorimetric sensor for determination of phosphate ions using anti-aggregation of 2-mercaptoethanesulfonate-modified silver nanoplates and europium ions , 2019, Sensors and Actuators B: Chemical.

[27]  Yongming Guo,et al.  In situ formed nanomaterials for colorimetric and fluorescent sensing , 2019, Coordination Chemistry Reviews.

[28]  S. Dong,et al.  Single-atom nanozymes , 2019, Science Advances.

[29]  Jianming Pan,et al.  Pyrophosphate-Mediated On–Off–On Oxidase-Like Activity Switching of Nanosized MnFe2O4 for Alkaline Phosphatase Sensing , 2019, Journal of Analysis and Testing.

[30]  Abdulmujeeb T. Onawole,et al.  Quantum chemical approach for chemiluminescence characteristics of di-substituted luminol derivatives in polar solvents , 2019, Journal of Molecular Liquids.

[31]  Wenxin Zhu,et al.  Portable Colorimetric Detection of Mercury(II) Based on a Non-Noble Metal Nanozyme with Tunable Activity. , 2019, Inorganic chemistry.

[32]  Xiaogang Qu,et al.  Carbon Nanozymes: Enzymatic Properties, Catalytic Mechanism, and Applications. , 2018, Angewandte Chemie.

[33]  C. Huang,et al.  Highly selective detection of phosphate ion based on a single-layered graphene quantum dots-Al3+ strategy. , 2018, Talanta.

[34]  Chengzhou Zhu,et al.  Single-Atom Electrocatalysts. , 2017, Angewandte Chemie.

[35]  W. Zhou,et al.  A flexible metal–organic framework with a high density of sulfonic acid sites for proton conduction , 2017 .

[36]  Yuyan Shao,et al.  Single Atomic Iron Catalysts for Oxygen Reduction in Acidic Media: Particle Size Control and Thermal Activation. , 2017, Journal of the American Chemical Society.

[37]  V. Bansal,et al.  Competitive Inhibition of the Enzyme-Mimic Activity of Gd-Based Nanorods toward Highly Specific Colorimetric Sensing of l-Cysteine. , 2017, Langmuir : the ACS journal of surfaces and colloids.

[38]  Juanjuan Liu,et al.  Red Emission B, N, S-co-Doped Carbon Dots for Colorimetric and Fluorescent Dual Mode Detection of Fe3+ Ions in Complex Biological Fluids and Living Cells. , 2017, ACS applied materials & interfaces.

[39]  Hui Xie,et al.  Atomically Dispersed Iron-Nitrogen Species as Electrocatalysts for Bifunctional Oxygen Evolution and Reduction Reactions. , 2017, Angewandte Chemie.

[40]  Tarun Kumar Sharma,et al.  Aptamer-controlled reversible inhibition of gold nanozyme activity for pesticide sensing. , 2014, Analytical chemistry.

[41]  Mengsu Yang,et al.  A dual-mode nanosensor based on carbon quantum dots and gold nanoparticles for discriminative detection of glutathione in human plasma. , 2014, Biosensors & bioelectronics.

[42]  Thawatchai Tuntulani,et al.  Cysteamine CdS quantum dots decorated with Fe3+ as a fluorescence sensor for the detection of PPi. , 2014, Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.

[43]  Huzhi Zheng,et al.  Analytical and environmental applications of nanoparticles as enzyme mimetics , 2012 .

[44]  Yu-Chie Chen,et al.  Using gold nanoclusters as selective luminescent probes for phosphate-containing metabolites. , 2012, Analytical chemistry.

[45]  Cai‐Feng Wang,et al.  Facile access to versatile fluorescent carbon dots toward light-emitting diodes. , 2012, Chemical communications.

[46]  Qinlong Wang,et al.  Carbon nanodots as peroxidase mimetics and their applications to glucose detection. , 2011, Chemical communications.

[47]  Lin Shao,et al.  Catalyst-free synthesis of nitrogen-doped graphene via thermal annealing graphite oxide with melamine and its excellent electrocatalysis. , 2011, ACS nano.

[48]  X. Qu,et al.  Multicolor luminescent carbon nanoparticles: Synthesis, supramolecular assembly with porphyrin, intrinsic peroxidase-like catalytic activity and applications , 2011 .

[49]  H. Jüppner,et al.  Phosphate sensing. , 2011, Advances in chronic kidney disease.

[50]  Erkang Wang,et al.  Fe3O4 magnetic nanoparticles as peroxidase mimetics and their applications in H2O2 and glucose detection. , 2008, Analytical chemistry.

[51]  Ya‐Ping Sun,et al.  Quantum-sized carbon dots for bright and colorful photoluminescence. , 2006, Journal of the American Chemical Society.