An Advanced Hand-Held Microfiber-Based Sensor for Ultrasensitive Lead Ion Detection.

This study demonstrated a l-glutathione-modified nonadiabatic microfiber sensor to detect a trace level of heavy metal ions in aqueous solution. The sensor showed an exclusively selective response to Pb among other metal ions and a measured detection limit of 5 μg/L, lower than the maximum allowable limit of Pb in drinking water by the World Health Organization. Moreover, a novel compact all-fiber-based interrogation scheme was proposed to promote the development of a portable hand-held system for on-site measurement.