Chemiluminescence System with Air Pump as a Sensor for Determination of Metal Levels in Rain

A lab-made chemiluminescence system with air pump was developed for monitoring of some metal levels in rain. The air pump enabled injection of 17.7 μg samples into a glass cell filled with luminol-H₂O₂ reagent of typically 300 μL for chemiluminescence measurement. The monitored trend of total metal ions in the rain collected in our campus was compared with analytical results of each metal ion from GFAAS. The system was also demonstrated to determine Cr⁶⁺ by reduction to Cr³⁺ using SnCl₂. The limit of detection for Cr⁶⁺ obtained by 4 measurements was 85.0 pg mL^-1 with a relative standard deviation of 3.4%. Although this system doesn't have selectivity due to the characteristics of chemiluminescence, application of it to environmental monitoring as a sensor for some transition metal ions was demonstrated