The heavy metal detector, crafted using a patented, innovative nanocomposite material, achieves an exceptionally low detection limit of less than 1 ppb for lead. We have developed novel automated methods for pH adjustment and temperature compensation specifically for heavy metal detection. As a result, our detection system maintains high accuracy and precision in the field detection of heavy metals without the need for pretreatment and calibration. This effectively addresses challenges associated with the limitations of rapid on-site water quality monitoring.Â