A compact short-path electrothermal vaporization-atmospheric pressure glow discharge atomic emission spectrometry device for the determination of cadmium and lead.

This study details the design and construction of a compact electrothermal vaporization-atmospheric pressure glow discharge atomic emission spectrometry (ETV-APGD-AES) device. A "short-path" transmission architecture was developed by drastically minimizing the physical distance between the tungsten coil (W-coil) vaporization zone and the plasma core. Operating parameters were optimized individually for cadmium (Cd) and lead (Pb) based on their distinct properties, enabling sequential determination. This short-path design achieves a compact physical footprint, entirely eliminating conventional, complex transfer tubes and significantly reducing both dead volume and system dimensions. Combined with a step-wise programmed heating protocol for the W-coil, the system achieves temporal separation of the target elements from the aqueous matrix, effectively mitigating water vapor interference on the low-power microplasma. Under optimal conditions, the limits of detection (LODs) for Cd and Pb were 1.0 µg L-1 and 5.1 µg L-1, respectively, with relative standard deviations (RSDs) for parallel measurements below 6.5%. Method accuracy was validated using certified reference materials and environmental water samples. The proposed device substantially enhances hardware integration while maintaining practical analytical performance, providing a valuable reference for developing low-cost, portable platforms for the on-site analysis of trace metals.