Elemental imaging using laser-induced breakdown spectroscopy: A new and promising approach for biological and medical applications

Biological tissues contain various metal and metalloid ions that play different roles in the structure and function of proteins and are therefore indispensable to several vital biochemical processes. In this review, we discuss the broad capability of laser-induced breakdown spectroscopy (LIBS) for in situ elemental profiling and mapping of metals in biological materials such as plant, animal and human specimens. These biological samples contain or accumulate metal species and metal-containing compounds that can be detected, quantified, and imaged. LIBS enables performing microanalysis, mapping and depth profiling of endogenous and exogenous elements contained in the tissues with a parts-per-million scale sensitivity and microscopic resolution. In addition, this technology generally requires minimal sample preparation. Moreover, its tabletop instrumentation is compatible with optical microscopy and most elements from the periodic table. Specifically, low- and high-atomic-number elements can be detected simultaneously. Recent advances in space-resolved LIBS are reviewed with various examples from vegetable, animal and human specimens. Overall, the performance offered by this new technology along with its ease of operation suggest innumerable applications in biology, such as for the preclinical evaluation of metal-based nanoparticles and in medicine, where it could broaden the horizons of medical diagnostics for all pathologies involving metals. (C) 2017 Elsevier B.V. All rights reserved.