Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Turnover Number and Catalytic Efficiency

Turnover Number and Catalytic Efficiency

The turnover number of an enzyme is the maximum number of substrate molecules it can transform per unit time. Turnover numbers for most enzymes range from 1 to 1000 molecules per second. Catalase has the known highest turnover number, capable of converting up to 2.8×106 molecules of hydrogen peroxide into water and oxygen per second. Lysozyme has the lowest known turnover number of half a molecule per second.
Chymotrypsin is a pancreatic enzyme that breaks down proteins during digestion....

Catalytically Perfect Enzymes

Catalytically Perfect Enzymes

The theory of catalytically perfect enzymes was first proposed by W.J. Albery and J. R. Knowles in 1976. These enzymes catalyze biochemical reactions at high-speed. Their catalytic efficiency values range from 108-109 M-1s-1. These enzymes are also called 'diffusion-controlled' as the only rate-limiting step in the catalysis is that of the substrate diffusion into the active site. Examples include triose phosphate isomerase, fumarase, and superoxide dismutase.

Most enzymes...

Reduction of Alkenes: Catalytic Hydrogenation

Reduction of Alkenes: Catalytic Hydrogenation

Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...

Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation

Reduction of Benzene to Cyclohexane: Catalytic Hydrogenation

Unlike the easy catalytic hydrogenation of an alkene double bond, hydrogenation of a benzene double bond under similar reaction conditions does not take place easily. For example, in the reduction of stilbene, the benzene ring remains unaffected while the alkene bond gets reduced. Hydrogenation of an alkene double bond is exothermic and a favorable process. In contrast, to hydrogenate the first unsaturated bond of benzene, an energy input is needed; that is, the process is endothermic. This is...

Molecular Models

Molecular Models

Physical models representing molecular architectures of chemical compounds play essential roles in understanding chemistry. The use of molecular models makes it easier to visualize the structures and shapes of atoms and molecules.

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Reduction of Alkenes: Asymmetric Catalytic Hydrogenation

Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Aptamer-Functionalized DNA Tetrahedra Loading GOx/HRP Cascade System for Targeted Therapy of Infected Wounds.

ACS applied materials & interfaces·2026

Same author

Programmable Assembly of Artificial Antigen-Presenting Cells with Framework Nucleic Acids.

Nano letters·2026

Same author

Hepatocyte TrkB Acts as a Gatekeeper Against MASH-Related Liver Fibrosis by Suppressing the TGFβ/CCL2 Axis and Macrophage Infiltration.

Cell proliferation·2026

Same author

Spatially Defined DNA Origami Cell Engagers for T and Natural Killer Cell-Mediated Immune Modulation.

ACS nano·2026

Same author

Awareness, Understanding, and Use of Nutrition Labels on Pre-Packaged Foods and Their Associations with Noncommunicable Diseases Among Adults in Shanghai, China.

Nutrients·2026

Same author

Concentration Imbalance-Driven Nucleotide Circuit for Tick-Borne Encephalitis Virus Detection via Hybridization-Responsive DNA-Templated Silver Nanoclusters.

Nano letters·2025

Search research articles

Related Experiment Video

Updated: Feb 15, 2026

Fragmenting Bulk Hydrogels and Processing into Granular Hydrogels for Biomedical Applications

Fragmenting Bulk Hydrogels and Processing into Granular Hydrogels for Biomedical Applications

Published on: May 17, 2022

Logic Catalytic Interconversion of G-Molecular Hydrogel.

Ruibo Zhong^1,2, Mingshu Xiao¹, Changfeng Zhu

¹Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University , 500 Dongchuan Road, Shanghai 200241, P. R. China.

ACS Applied Materials & Interfaces

|January 17, 2018

Summary

This study introduces an artificial enzyme hydrogel (AEH) for highly sensitive lead (Pb²⁺) detection. The AEH system leverages G-quadruplex (G₄) stabilization changes to achieve precise Pb²⁺ sensing and biomolecular computation.

Keywords:

G-quadruplex Pb2+ detection artificial enzyme hydrogel catalytic interconversion logic gate

More Related Videos

Transport Properties of Ibuprofen Encapsulated in Cyclodextrin Nanosponge Hydrogels: A Proton HR-MAS NMR Spectroscopy Study

Transport Properties of Ibuprofen Encapsulated in Cyclodextrin Nanosponge Hydrogels: A Proton HR-MAS NMR Spectroscopy Study

Published on: August 15, 2016

Synthesis of an Intein-mediated Artificial Protein Hydrogel

Synthesis of an Intein-mediated Artificial Protein Hydrogel

Published on: January 27, 2014

Related Experiment Videos

Last Updated: Feb 15, 2026

Fragmenting Bulk Hydrogels and Processing into Granular Hydrogels for Biomedical Applications

Fragmenting Bulk Hydrogels and Processing into Granular Hydrogels for Biomedical Applications

Published on: May 17, 2022

Transport Properties of Ibuprofen Encapsulated in Cyclodextrin Nanosponge Hydrogels: A Proton HR-MAS NMR Spectroscopy Study

Transport Properties of Ibuprofen Encapsulated in Cyclodextrin Nanosponge Hydrogels: A Proton HR-MAS NMR Spectroscopy Study

Published on: August 15, 2016

Synthesis of an Intein-mediated Artificial Protein Hydrogel

Synthesis of an Intein-mediated Artificial Protein Hydrogel

Published on: January 27, 2014

Area of Science:

Biomolecular Engineering
Nanomaterials
Chemical Sensing

Background:

G-quadruplex (G₄) structures are crucial in biological processes and have been explored for biosensing applications.
Developing sensitive and selective methods for detecting heavy metal ions like lead (Pb²⁺) is critical for environmental and health monitoring.
Artificial enzyme hydrogels (AEHs) offer a promising platform for developing novel biosensing systems.

Purpose of the Study:

To construct an artificial enzyme hydrogel (AEH) system for sensitive and selective detection of lead ions (Pb²⁺).
To investigate the mechanism of Pb²⁺-induced conformational changes and activity loss in the AEH.
To explore the potential of the AEH system for biomolecular computation.

Main Methods:

Cation-templated self-assembly of guanosine and KB(OH)₄ to incorporate hemin into G-quadruplex (G₄) structures, forming an AEH.
Utilizing the differential stabilization of G₄ by Pb²⁺ versus K⁺ to trigger hemin release and loss of enzyme activity.
Characterizing the AEH response to varying concentrations of Pb²⁺ and other metal ions.

Main Results:

The AEH system demonstrated highly sensitive and selective detection of Pb²⁺ within a range of 1 pM to 50 nM, with a limit of detection of approximately 0.32 pM.
Pb²⁺ ions were found to be more efficient than K⁺ in stabilizing G₄, leading to Pb²⁺-induced hemin release and loss of AEH activity.
The system exhibited high selectivity for Pb²⁺ over other tested metal ions and was successfully used to construct two-input INHIBIT logic gates.

Conclusions:

The developed AEH-based system provides a novel and effective platform for the ultrasensitive and selective detection of Pb²⁺.
The Pb²⁺-induced catalytic interconversion mechanism offers a robust sensing strategy with a significantly lower detection limit compared to previous G₄-DNAzyme methods.
The AEH system's versatility opens new avenues for advanced sensing applications and biomolecular computation.