Rapid identification of elements in liquid by using pulse carbon dioxide laser-induced plasma spectroscopy

Identification of major elements in milk liquid has been rapidly carried out by using pulse carbon dioxide (CO2) laser. Experimentally, a milk liquid was poured on a Cu metal plate to make a thin film on the metal surface. The liquid was then dried at 100°C for 5 minute. A thin film of milk liquid was produced with a thickness of around 0.1 mm. The Cu plate only functions as a metal subtarget. A pulse CO2 laser was irradiated on a metal surface to induce a luminous plasma. The atomization of liquid and excitation processes of atoms from the film sample happen in the plasma region. Various major elements in milk liquid, namely Ca, Mg, Na, and K can successfully be detected. Therefore, the method has high-prospect for major elemental analysis in liquid sample target.