Research projects in Sekretareva Group

Our current work focuses on investigations of plasmon-driven electrocatalysis at single plasmonic nanoparticles and on development of new single-molecule electrochemical techniques for studies of enzymatic catalysis, particularly focusing on oxygen reduction reaction catalyzed by multicopper oxidases. Other collaborative work include mechanistic studies of hydrogenase catalysis by protein film electrochemistry and examination of heme-based biomimetic catalysts by electron paramagnetic resonance spectroscopy.

Plasmon-driven electrocatalysis

Solar energy, being an abundant and readily available energy resource, possesses great potential in driving environmentally benign chemical transformations. Plasmonic nanoparticles have attracted particular attention as an effective material for solar to chemical energy conversion due to their intrinsic property to generate hot (highly energetic) charge carriers upon illumination. Utilization of hot carriers in chemical synthesis, however, is impeded by their short relaxation times, resulting in low quantum yields. This project aims at developing a single-particle method based on single entity electrochemistry to quantify the interplay between different factors that affect the overall performance of plasmon-driven chemical synthesis and guide the design of highly efficient catalytic materials.

Single enzyme electrocatalysis

While redox proteins have been studied for over a century, several important fundamental questions remain open: 

  • What are the intrinsic rates of electron transfer in single redox proteins, and can they be controlled to manipulate catalytic properties? 
  • Are there temporal variations in the electron transfer rates, and can they be correlatedto conformational changes? 
  • What role does protein dynamics play in electron transfer and catalysis?

Studies of redox proteins at the single-molecule level are essential to answer these questions since this kind of effects would be averaged out in an ensemble of molecules. Electrochemical methods are naturally considered as an ideal approach to study processes of electron transfer. However, direct measurements of small electrical currents associated with single enzyme molecules are experimentally challenging. In this project we are working on the development of novel detection platforms enabling single-molecule studies of redox proteins.

Last modified: 2021-10-01