Journal: Physical Review Letters 126, 126001 (2021)
Author: Jingyu Kang1,2, Seong Jun Park1,2, Ji-Hyun Kim1,2, Peng Chen3*, and Jaeyoung Sung1,2*
1 Creative Research Initiative Center for Chemical Dynamics in Living Cells, Chung-Ang University, Seoul 06974, Korea
2Department of Chemistry, Chung-Ang University, Seoul 06974, Korea
3Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, USA.
DOI: https://doi.org/10.1103/PhysRevLett.126.126001
Catalytic reaction events occurring on the surface of a nanoparticle constitute a complex stochastic process. Although advances in modern single molecule experiments enable direct measurements of individual catalytic turnover events occurring on a segment of a single nanoparticle, we do not yet know how to measure the number of catalytic sites in each segment or how the catalytic turnover counting statistics and the catalytic turnover time distribution (CTD) are related to the microscopic dynamics of catalytic reactions. Here, we address these issues by presenting a stochastic kinetics for nanoparticle catalytic systems. We propose a new experimental measure of the number of catalytic sites in terms of the mean and variance of the catalytic event count. By considering three types of nanocatalytic systems, we investigate how the mean, the variance, and the distribution of the catalytic turnover time depend on the catalytic reaction dynamics, the heterogeneity of catalytic activity, and communication among catalytic sites. This work enables accurate quantitative analyses of single molecule experiments for nanocatalytic systems and enzymes with multiple catalytic sites.