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Laser-induced breakdown spectroscopy (LIBS) is a powerful analytical technique for elemental analysis, but matrix effects can significantly affect its accuracy. In this work, we propose the use of calibration-free LIBS (CF-LIBS) with the one-point calibration (OPC) method to reduce matrix effects in the quantification of mercury (Hg) for seven soil and eleven landfill leachate samples, with Hg concentration ranging from 50 to 1000 mg kg−1. To improve sensitivity, we employed a double-pulse LIBS system with parameters optimized for each of the two sample matrices. A single soil sample was used to calibrate the OPC factors, which were then applied to the CF-LIBS calculations for the other samples. Using CF-LIBS corrected with the OPC method, we achieved an average error of 4.3% in the quantification of Hg for the two sample sets. This result indicates that these methods have the potential not only to reduce matrix effects but also to compensate for variations in LIBS system optimization for either matrix (soils and leachates) in the quantification of Hg. Therefore, the combination of these methods opens new possibilities for LIBS analyses, where the system can be optimized for each element and sample matrix, and the quantification can be performed with CF-LIBS, as long as the requirements for local thermodynamic equilibrium are fulfilled. Further studies with other elements, matrices, and measurement conditions are needed to validate and expand these findings. [ABSTRACT FROM AUTHOR]

A chronological review is provided of the progress achieved in the last two decades in the use of the Laser-Induced Breakdown Spectroscopy (LIBS) technique on cementitious materials analysis. The first part of this review provides a brief overview of LIBS equipment and chemometric approaches to LIBS analysis. The second part of the review describes LIBS applications for concrete and cement analysis, such as elemental identifications, qualitative and quantitative analysis, and optimized LIBS systems. The detection of elements such as Cl and S was highlighted in applications in the early 2000s, followed by element quantification and, more recently, the reduction of their limit of detection (LOD) through LIBS setup improvements. The potential and versatility of LIBS in the analytical analysis of cementitious materials are highlighted in chronological order. Finally, some critical final considerations are provided, followed by a future perspective on cement and concrete applications. • In the last twenty years, LIBS has aroused great interest in cementitious materials. • The chronological evolution of LIBS applications in concrete and cement are reviewed. • Detection of elements such as Cl and S is highlighted in applications in the early 2000's. • Substantial progress has been achieved in signal detection, instrument portability and new methods. [ABSTRACT FROM AUTHOR]

In this Part II of the review the applications in the last decade (2010–2019) of Laser-Induced Breakdown Spectroscopy (LIBS) to the study of crop plants and their products and food derivatives, also in combination with novel methodological and statistical approaches, are discussed. In particular, LIBS applications to the analysis of plant leaves, vegetables, tubers, roots, grains, seeds, fruits, and processed vegetal products, such as commercial coffee, flours and wine, are reviewed. The new trends of LIBS in the analysis of various crops of economic value, such as sugarcane, tobacco, peppermint and saffron, and as a diagnostic tool for citrus, soybean and tobacco diseases are also reviewed. Further, the potential of recent advanced LIBS approaches, including double-pulse (DP)-LIBS, femtosecond (fs)-LIBS, micro-LIBS, nanoparticle-enhanced (NE) LIBS and 3D elemental imaging, to agricultural products is discussed. Finally, new trends and future perspectives of LIBS as an efficient analytical tool to be extended to other plant species, cultivars and their derivatives are highlighted. • LIBS elemental analysis of plants and food derivatives raised a high interest in the last decade. • LIBS applications to the analysis of plant leaves, vegetables, tubers, roots, grains, seeds and fruits are reviewed. • New trends of LIBS are commented in the analysis of various crops and food derivatives of economic value. [ABSTRACT FROM AUTHOR]

A review is provided on the last decade (2010–2019) applications of Laser-Induced Breakdown Spectroscopy (LIBS) technique to agricultural materials, including soils and fertilizers, also in combination with novel methodological and statistical approaches. In particular, the potential of double-pulse (DP)-LIBS, femtosecond (fs)-LIBS, micro-LIBS, nanoparticle-enhanced LIBS, and 3D elemental imaging and other recent advanced LIBS approaches for application to the study of soils and fertilizers is discussed. Finally, new trends and future perspectives of LIBS as an efficient analytical tool to be extended to other soil and fertilizer issues are highlighted. • LIBS raised a high interest for its advantages in measuring elements in soils and fertilizers. • LIBS instrumentation, principles, and chemometric methods for analysis are reviewed. • New trends of LIBS are commented in the analysis of soils and fertilizers. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) have shown interesting properties and specific biofunctions, providing benefits and new opportunities for controlled release systems. In this research, we demonstrated the use of natural rubber latex (NRL) from Hevea brasiliensis as a carrier of AuNPs and the antibiotic metronidazole (MET). We prepared AuNP-MET-NRL and characterized by physicochemical, biological and in vitro release assays. The effect of AuNPs on MET release was evaluated using UV–Vis and Laser-Induced Breakdown Spectroscopy (LIBS) techniques. AuNPs synthesized by Turkevich and Frens method resulted in a spherical shape with diameters of 34.8 ± 5.5 nm. We verified that there was no emergence or disappearance of new vibrational bands. Qualitatively and quantitatively, we showed that the MET crystals dispersed throughout the NRL. The Young's modulus and elongation values at dressing rupture were in the range appropriate for human skin application. 64.70% of the AuNP-MET complex was released within 100 h, exhibiting a second-order exponential release profile. The LIBS technique allowed monitoring of the AuNP release, indicating the Au emission peak reduction at 267.57 nm over time. Moreover, the dressing displayed an excellent hemocompatibility and fibroblast cell viability. These results demonstrated that the AuNP-MET-NRL wound dressing is a promising approach for dermal applications. • A wound dressing was developed using AuNPs and metronidazole loaded into NRL. • The reduction of the Au signal verified by LIBS proved to be an efficient approach in the identification of AuNP released • 64.7% of the AuNPs-metronidazole complex was released by the polymeric matrix • Wound dressing was biocompatible in hemolytic tests, beyond to contributing to the fibroblasts proliferation. [ABSTRACT FROM AUTHOR]