Domain-Limited Sub-Nanometer Co Nanoclusters in Defective Nitrogen Doped Carbon Structures for Non-Invasive Drug Monitoring.

In this work, sub-nanometer Co clusters anchored on porous nitrogen-doped carbon (C─N─Co NCs) are successfully prepared by high-temperature annealing and pre-fabricated template strategies for non-invasive sensing of clozapine (CLZ) as an efficient substrate adsorption and electrocatalyst. The introduction of Co sub-nanoclusters (Co NCs) provides enhanced electrochemical performance and better substrate adsorption potential compared to porous and nitrogen-doped carbon structures. Combined with ab initio calculations, it is found that the favorable CLZ catalytic performance with C─N─Co NCs is mainly attributed to possessing a more stable CLZ adsorption structure and lower conversion barriers of CLZ to oxidized state CLZ. An electrochemical sensor for CLZ detection is conceptualized with a wide operating range and high sensitivity, with monitoring capabilities validated in a variety of body fluid environments. Based on the developed CLZ sensing system, the CLZ correlation between blood and saliva and the accuracy of the sensor are investigated by the gold standard method and the rat model of drug administration, paving the way for non-invasive drug monitoring. This work provides new insights into the development of efficient electrocatalysts to enable drug therapy and administration monitoring in personalized healthcare systems.