Enlarged spectral range in Calibration Free - Laser Induced Breakdown Spectroscopy for the qualitative and quantitative analysis of a complex bone matrix

Abstract

In this work, Calibration Free - Laser Induced Breakdown Spectroscopy is applied for the qualitative and quantitative elemental analysis in the rib bone of a wild boar, which is a complex matrix. The sample was obtained from the rib bone of a wild boar. The sample contains major elements such as calcium and phosphorus and other minor and trace elements such as magnesium and strontium, among others. The LIBS application provided by NIST was used for the simulation of the plasma cooling. The intensities of emission lines were calculated at different conditions (varying plasma temperature Te and electron density ne simultaneously) depending on the plasma cooling process. The obtained results allowed the determination of the range of suitable values of ne and Te for the experimental measurements and optimization of the Saha-Boltzmann plot. The sample was measured for delay times of 100, 300, 500 and 1000 ns at a low pressure of 13 mbar in an argon atmosphere. From the measured data, suitable lines of Ca, Mg, P, Sr, O, and H were identified and chosen in Vacuum UV – NIR range for the reliable calculation of the Te of plasma for the bone sample for different delays. The Ca/P was obtained by calculating the atomic and mass percentages of the elements present in the bone sample.