2022 Volume 76 Issue 1 Pages 43-49
We developed a simple flow-injection analytical （FIA） system to determine boron in natural water samples fluorometrically. The system had two newly-developed components: one was the flow system using small and low-power consumption micro-ring pumps, and the other was a compact fluorometric detector using an ultra-violet light-emitting diode （UV-LED） with a photocurrent integration circuit. These components contributed to the cost reduction and downsizing of the system. The detector dimensions and mass were 125×90× 60 mm and 400 g, respectively. The fluorometric reagent for boron was chromotropic acid, reported as a highly sensitive reagent. Parameters for the system, such as reaction coil length, and sample injection volume, were optimized. After optimization, its linear dynamic range and the limit of detection （LOD） for boron were 0 to 0.5 mg L－1 and 0.017 mg L－1, respectively. The sample throughput was 20 h－1. We successfully applied this FIA system to determine boron in river and seawater samples.
