Laser induced-thermal lens spectrometry in combination with dispersive liquid–liquid microextraction for trace analysis Original Research Article

A new combination method including laser induced-thermal lens spectrometry (LI-TLS) and dispersive liquid–liquid micro extraction (DLLME) was developed and used for determination and preconcentration of trace amount of lead in liquid samples. Thermal lens spectrometry is suitable for determination of analyte after DLLME because of the low volume of the remained phase after DLLME and increasing of the enhancement factor for the non polar organic solvents. Non polar organic solvents have the ideal conditions for this combination because of low thermal conductivity and large variation in refractive index with temperature. In this method; ethanol, carbon tetrachloride and 1,5-diphenyl thiocarbazone (dithizone), were used as disperser solvent, extraction solvent and chelating agent, respectively.