Lithium Detection in Peripheral Biofluids Using a Smart Electrochemical Sensor

This study proposes the development of a smart sensing platform based on graphite screen-printed electrodes (SPEs) for lithium determination by potentiometric measurements. The SPEs were modified by electrodeposition of gold and silver nanoparticles ((Au&Ag)NPs); then, a lithium-selective membrane was deposited by drop-casting onto the nanostructured surfaces. The electrochemical platform was tested with a pocket instrument connected to a smartphone for decentralized analysis. A calibration curve was built within the range 10−5−10−1 M Li+ with a detection limit of 1.6 µM. Finally, the sensing platform was successfully applied for lithium determination in clinical complex matrices as synthetic sweat and saliva.