Elemental analysis of gallstone samples by utilizing LIBS and ICP-MS approaches

In this study, the elemental composition of gallstone samples was carried out by laser-induced breakdown spectroscopy (LIBS) and inductively coupled plasma mass spectrometry (ICP-MS). Twelve gallstones were surgically removed and collected from different patients for further analysis. Metals concentration in the investigated samples were found at different levels. P, Ca and S showed significant concentration levels, while the Fe, Al, Ni, Ti and Sn present in lower concentrations. Laser-induced plasma has been evaluated by measuring electron density and electron temperature as a function of laser energy. LIBS spectra are acquired in the spectral region (350-550 nm) after adjusting experimental circumstance for maximum signal intensity. Calibration curves (C.C) for S, Ca, P, Fe, Al, Ni, Ti and Sn are established based on gallstone samples with known element concentrations verified by ICP-MS. Calibration curves have been tested to calculate the element content of three additional samples. The relative errors between LIBS and ICP-MS obtained for examined elements vary from about 1.33 to 11.8%.