The Italy – Argentina round table under the working title Advances in Laser Induced Breakdown Spectroscopy (LIBS) applications was held on 17.10.2025. at the University of Bari, Department of Chemistry. Milica held a lecture titled “LIBS for the determination of trace metals in oils”.

13^th International Conference on Photo-Excited Processes and Application was held at the Castle of Charles V in Lecce, Italy, from September 14 to 19, 2025. Milica participated with a poster entitled LIBS Analysis of Oils: A Spin-Coating Approach for High Sensitivity and Matrix Effect Suppression, while the abstract of the poster is given below:

We present a methodology for the preparation and elemental analysis of oil samples using Laser-Induced Breakdown Spectroscopy (LIBS), designed to reduce matrix effects and sample
volume while improving sensitivity and repeatability. The sample preparation involves stabilizing both the oil and a silica wafer substrate at a fixed temperature of 40 °C, followed by deposition of an oil droplet on substrate rotated by a spin coater, thus producing uniform thin films with tunable thickness governed by rotation speed [1].
This approach enables consistent sampling, independent of the oil’s kinematic viscosity, and ensures a reproducible interaction volume for LIBS. Comparative measurements on pure oil and oil samples containing various elements revealed that matrix effect is significantly mitigated in thin oil films. For ultra-thin layers (~0.74 μm), the LIBS signal—particularly the carbon line—becomes stable and insensitive to impurity concentration, a key indicator of minimized matrix interference. Furthermore, pulse-to-pulse stability and electron density were significantly enhanced compared to bulk liquid targets, due to better plasma confinement [2]. Despite the minimal ablation volume (~0.3 nL per pulse), strong plasma emission was achieved. Using optimized delay times and line-specific calibration, we attained detection limits as low as 3.9 ppm for Zn, 0.49 ppm for Cd, 0.16 ppm for Cu, and 0.082 ppm for Cr. This method provides a highly sensitive and efficient pathway for trace elemental analysis in oil-based matrices [1].
References:
[1] M. Vinić, E. Aruffo, F. Andreoli, M. Ivković, V. Lazic, Spectrochimica Acta Part B: Atomic
Spectroscopy, 164, 105765 (2020)
[2] M. Vinić, M. Kuzmanović, J. Savović, M. Ivković, Journal of the Serbian Chemical Society 88 (2),
153 (2022)

Milica give a lecture at PHOTONICA 2025 conference held at Serbian Academy of Science and Arts in Belgrade from 25^th August to 29^th August 2025. The title of the talk was Enhancement of LIBS Signal via NELIBS and LIPSS for Biomedical Applications while the abstract of the talk is given below:

Laser-Induced Breakdown Spectroscopy (LIBS) has emerged as a promising technique for elemental analysis in complex matrices, including biological fluids. However, its sensitivity – especially for trace elements – remains a critical limitation when targeting subtle biochemical differences such as those potentially associated with neurodevelopmental disorders like Autism Spectrum Disorder (ASD) [1]. In this context, signal enhancement strategies are essential to increase LIBS performance
and unlock its potential in clinical diagnostics. In this work, we present our preliminary results on two distinct signal enhancement approaches: Nanoparticle-Enhanced LIBS (NELIBS) and the application of Laser-Induced Periodic Surface Structures (LIPSS). Both methods aim to improve signal intensity and reproducibility in LIBS measurements by altering the physical properties of the substrate or sample–substrate interface. Our experimental setup involves the analysis of aqueous PbCl₂ solutions and blood serum
microdroplets deposited and dried on solid substrates. For NELIBS, substrates were functionalized with noble metal nanoparticles, known to facilitate localized plasma confinement and improved ablation efficiency. In parallel, LIPSS were fabricated on the same substrates using controlled laser irradiation, creating periodic nanostructures that enhance light–matter interaction during plasma generation. The enhanced LIBS spectra were compared with conventional LIBS for both PbCl₂ and serum
samples, focusing on signal-to-noise ratio, emission intensity, and spectral reproducibility. Our findings confirm that both NELIBS and LIPSS contribute to notable signal enhancement. The observed enhancements suggest increased sensitivity for trace element detection in complex biological fluids. These results represent a first step toward applying advanced LIBS-based techniques for biomedical diagnostics. The long-term objective of our research is to develop a robust metallomic profiling method capable of detecting elemental biomarkers potentially associated with ASD. Future work will focus on applying these optimized LIBS protocols to real blood serum samples from pediatric subjects with ASD and neurotypical controls. This study highlights the promise of physical and chemical substrate modifications for pushing the analytical limits of LIBS and opens new perspectives for its application in non-invasive and rapid diagnostic workflows.

[1] J.K. Kern et al, Journal of Trace Elements in Medicine and Biology 38 (2016) 8.

IX International School and Conference on Photonics was held in Belgrade from 28^th August to 1^st September. Milica was invited to give a progress report on her work on application of LIBS in determination of trace metals in oils. The talk was entitled Application of laser-induced breakdown spectroscopy for the determination of trace metals in oils.