Transuranic radionuclides such as uranium tend to be a pervasive environmental contaminant It is absorbed through the intestine or a lung deposited in the tissues predominantly kidney and bone and is carcinogenic A novel nanosensor system has been developed for voltammetric tracing of environmental uranium contamination The sensor consists of an organophosphorous ligand (t-butylphenyl)-N N-di-(isobutyl) carbamoyl-methylphosphineoxide (CMPO) functionalized superparamagnetic core-shell magnetic nanoparticles and magnet based electrodes It exploits the natural affinity of uranium for phosphate molecules to fabricate a highly specific and reproducible sensor The small dimension along with a dramatically increased contact surface has lead to a faster response and higher sensitivity The system uses an external magnetic field gradient for preconcentration and removal of the analyte from the surrounding aqueous media The redox propel ties of the analyte are exploited for enumeration of variables by electrochemical techniques such as square wave voltammetry The detection limit of the system is observed to be in parts-per-billion (ppb) of the uranyl concentration (C) 2010 Elsevier Ltd All rights reserved