Evaluation of femtosecond laser-induced breakdown spectroscopy for determination of chemical elements in biomedical samples

Abstract

The laser-induced breakdown spectroscopy (LIBS) is an analytical technique idealized for the direct determination of chemical elements. This technique is considered very promising for analysis of samples in different fields, such as environmental, agronomic, biomedical, forensic, among others. In many cases, the chemical characterization of solid, liquid or gaseous samples is surprisingly quick and simple, without the use of reactants or waste generation. However, mainly due to the effects of laser-sample interaction, the LIBS technique has been less applied in quantitative analyses. In order to eliminate or reduce the matrix effects the use of ultrashort laser pulses has been recommended. In many cases, stoichiometric sampling can be achieved by using these lasers in the ablation process. In this project, the LIBS technique with femtosecond lasers will be evaluated for determination of chemical elements in biomedical samples. Samples of animal tissues, bones, hair, and certified reference materials will be analyzed. The main factors affecting the performance of LIBS such as: sample characteristics and ablation processes; laser characteristics (i.e. fluence, pulse duration and frequency); measurement setup (i.e. delay time, integration time and number of accumulated pulses); spectroscopic interferences, and calibration strategies will be investigated. (AU)