Evaluation of the effect of laser and sample properties in the direct analysis of meats by laser induced breakdown spectroscopy (LIBS)

Abstract

Laser induced breakdown spectroscopy (LIBS) has been an attractive and fairly explored analytical technique for elemental analysis of environmental, agronomic, and industrial samples with minimal or no sample preparation. Besides of characteristics of the direct analysis techniques, LIBS is multielement and can be used in field analyzes due to availability of portable instruments. However, the quantitative analysis is still considered its "Achilles' heel" because of complex processes involved in the laser-sample interaction and calibration difficulties due to unavailability of solid standards. In this context, this research project aims to evaluate the effect of laser and sample properties, the ablation atmosphere and the parameters of optical emission measurement in the analytical performance of LIBS analysis of beef and chicken. The feasibility of use secondary reference materials for the calibration will also be evaluated. The materials studied will be the filter paper and / or cellulose, babaçu mesocarp, and lyophilised and ground meat samples with different levels of inorganic contaminants, macro and micronutrients. The accuracy of LIBS results will be estimated by means of comparison with determinations carried out by ICP OES.