Our research group focuses on the development of separation and analysis of rare earth elements and electrochemistry application for biosensors. The development of separation and analysis of rare earth elements involve application of various ligands, either novel ligands or synthetic ligands with regular extraction, membrane emulsion extraction, and another extraction method. The analysis is combined with multivariate analysis and chemometrics also applied in the development either in the chromatographic, spectrometric, or electrometric method. The rare earth elements have been developed for various applications including contrast agents, sensors, and biosensors. Biosensors for diagnostic and food analysis also use several rare earth elements.