Direct current glow discharges in atmospheric air (original) (raw)

In open air and without any type of inert gas, stable and bright micro plasma was successfully obtained using Liquid Sampling Atmospheric Pressure Glow Discharge (LS-APGD). The discharge current varied between 20 to 80 mA with a maximum voltage 550 V, discharge gap 0.5–2 mm and solution pH of 1. The produced plasma operates in the normal glow discharge region at a low power (11–40 W). For analytical application the linear dynamic range is obtained up to 500 µg mL−1. Limits of detection based on 3σ of the background intensity determined for Ca I (422.673 nm), Cu I (324.754 nm), Fe I (497.5 nm), and Zn I (213.856 nm) are 0.3, 0.65, 0.1, 0.7 µg mL−1 respectively.