Rapid and ultra-sensitive trace metals detection of water by partial Leidenfrost superhydrophobic array surface enhanced laser-induced breakdown spectroscopy.

ABSTRACT

The rapid and ultra-sensitive detection of trace elements in liquid is a primary concern for researchers. In this study, a partial Leidenfrost effect superhydrophobic (PLSHB) array surface was used for rapid in situ evaporation enrichment of sample droplets. Within 4 min, a 50 µL droplet sample was completely evaporated, resulting in all solutes in it being concentrated within a circular range measuring approximately 350 µm in diameter, without the formation of a coffee ring structure. The limits of detection for six metals (Pb, Ba, Be, Mn, Cr, Cu) in water were determined to be as follows 0.82 µgL-1, 0.27 µgL-1, 0.033 µgL-1, 0.136 µgL-1, 0.241 µgL-1, and 0.083 µgL-1. Furthermore, laser-induced breakdown spectroscopy (LIBS) was employed to detect the enriched solutes from ten liquid samples with identical concentrations on the PLSHB array surface; these measurements exhibited a relative standard deviation (RSD) of only 3.7%. Spike experiments involving the addition of the aforementioned six metals into drinking water demonstrated recovery rates ranging from 85.7% to 117.7%. Therefore, the application potential of PLSHB array surface enhanced LIBS for rapid, stable, and ultra-sensitive detection and analysis of trace metal elements across various fields such as industry, environmental science, and biomedicine might be highly promising.