Spectroscopic study on the interaction of Co2+ with citrate-Mn3O4: Towards the development of nanotherapy against cobalt toxicity

Abstract

Cobalt (Co) although, an essential element playing a key role in several physiological and biological processes, can transform into a potential toxin when present in higher amounts or in certain chemical forms. The increasing usage of transition metals in industries, agriculture, medicines and technology has led to an alarming rise in cobalt poisoning cases. Exposure to cobalt can cause several health hazards including neurodegenerative disorders like Alzheimer’s disease, Parkinson’s disease, etc. Cobalt may interact with several proteins in the cellular milieu, generating reactive oxygen species (ROS) and thereby triggering apoptosis of the neural cells via DNA damage. The most common method of removal of such metals from the body is by the use of metal chelators. In this study, we report a facile strategy for the clearance of Co (II) from the physiological milieu using citrate functionalized Mn3O4 NPs (C-Mn3O4 NPs). The chelation ability of C-Mn3O4 NPs has been evaluated using steady state and pico-second resolved optical spectroscopy. Our studies reveal that C-Mn3O4 NPs form a stable complex with cobalt ions, thereby reducing the ability of Co2+ to produce reactive oxygen species (ROS) via Fenton like reaction and hence function as a novel nanotherapeutic for the detoxification of cobalt in the human system.