LASER-ENHANCED IONIZATION DETECTION OF MAGNESIUM ATOMS BY A COMBINATION OF ELECTROTHERMAL VAPORIZATION AND FLAME ATOMIZATION

A system for the electrothermal vaporization flame atomization laser-e nhanced ionization (ETV-FL-LEI) detection of Mg was optimized and comp letely characterized. The vaporization, transport, atomization, probin g, and detection efficiencies were all determined experimentally. The overall efficiency of the system was found to be 0.002 51%. The experi mental detection limit of 2 ng ml(-1) (20 pg) for Mg was limited by no ise due to the blank signal. A detection limit of 590 fg ml(-1) (5.9 f g) could be achieved in the absence of the blank and a reduction of ra diofrequency noise.