In a system for chemical analysis, an RF-driven plasma ionization device including a pair of spaced-apart and plasma-isolated electrodes, the electrodes are connected to a power source wherein the electrodes act as plates of a capacitor of a resonant circuit, the gas electrically discharges and creates a plasma of both positive and negative ions, and the voltage is applied as a continuous alternating waveform or as a series of pulses, such as a packet waveform.