Related Experiment Video
Updated: Jun 27, 2026
A Method for Selecting Structure-switching Aptamers Applied to a Colorimetric Gold Nanoparticle Assay
Published on: February 28, 2015
Study on the binding mode of aptamer to ampicillin and its electrochemical response behavior in two different
Yangkejia Xiang1, Zhigang Yu2,3, Dan Liu1,4
1Post-Doctoral Research Center of Chongqing Key Laboratory of Inorganic Special Functional Materials, College of Chemistry and Chemical Engineering, Yangtze Normal University, Fuling, Chongqing, 408100, China.
Abstract:
A study was carried out to investigate the binding mode of aptamer to ampicillin (AMP) and its electrochemical response behavior. The binding mode was confirmed using the molecular dynamics (MD) simulation method to obtain the corresponding binding dynamic change process. Following the confirmed binding mode, a qualitative elucidation was provided on the electrochemical response characteristics of a single-probe aptamer-based folding sensor. The results show that there exist two different binding modes in two different solution systems, Phys2 and H2O (0.1 M NaCl). These two binding modes can respectively induce two different contraction changes, thereby driving the methylene blue (MB)-modified aptamer probe to show a "close-to-interface" convergence behavior with different degrees on the actual electrode surface, which validates two apparently different electrochemical response behavior characteristics of "signal-on" for the sensor. By contrast, H2O (0.1 M NaCl) as the reaction medium is more conducive to the formation of a stable aptamer/AMP complex and the development of a high-sensitivity analytical method with a low detection limit of 0.033 μM. The simulation results effectively support the experimental results, which is helpful in gaining a deeper understanding of the relationship between the signaling mechanism and practical analytical performance for aptamer-based folding sensors at the molecular level.
Related Concept Videos
01:22Protein-Drug Binding: Determination Methods
Indirect methods involve isolating the bound drug from its free form in biological samples such as blood, serum, or plasma. These techniques aim to measure the percentage of drugs bound to proteins. Equilibrium dialysis is a commonly used method where the free drug concentration at equilibrium is measured by separating the bound...
01:18Factors Affecting Protein-Drug Binding: Drug-Related Factors
One crucial factor in drug-protein binding is the drug's lipophilicity or its affinity for fat. More lipophilic drugs tend to have higher binding extents. For example, highly lipophilic drugs like cloxacillin exhibit substantial protein binding, with as much as 95% of the drug binding to proteins. In contrast,...