Nutritional and toxic elemental analysis of dry fruits using laser induced breakdown spectroscopy (LIBS) and inductively coupled plasma atomic emission spectrometry (ICP-AES).

Abstract

Quantitative investigation of essential and trace heavy elements present in health-beneficial dry fruits (Pistachio, Almonds, Black walnut, White walnut, and Cashew) was investigated using Laser Induced Breakdown Spectroscopy. For an accurate elemental exposure using LIBS technique, the local thermo-dynamical equilibrium of the laser induced plasma was established and verified using McWhirter criterion based on the electron number density in the plasma. Earlier to engage, our LIBS detector was optimized. For quantification of elements, standard calibration curves (CC)-LIBS method was applied. Using our LIBS system, the nutritional elements such as Al, Mg, Ca, Fe, K, Zn, and Na and toxins like Pb, Cr, and Cu were detected in dry fruits. The elemental quantification of dry fruit contents were validated using standard (ICP-AES) method and the relative accuracy of our experimental setup in comparison to ICP approach was in the ranging from 0.1 to 0.3 at 2.5-% error confidence.