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The substitution of petroleum-based polymers with naturally derived biopolymers may be a good alternative for the conservation of natural fossil resources and the alleviation of pollution and waste disposal problems. However, in order to be used in a wide range of applications, some biopolymers’ properties should be enhanced. In this study, biocompatible, non-toxic, and biodegradable chitosan (CS) film and CS reinforced with 10 wt% of cellulose nanocrystals (CN–CS) were coated with amorphous hydrogenated carbon layers (a–C:H) of different thickness. To investigate the effect of the nano-reinforcement on the a–C:H layer applied, mild radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) was used to coat the CS and its CN–CS bio-nanocomposite film. Both the surface characteristics and the chemical composition were analyzed. The surface morphology and wettability were examined by ex-situ atomic force microscopy (AFM) and contact angle measurements (CA), respectively. Hereby, the relationship between sp2/sp3 ratios on a macroscopic scale was also evaluated. For the investigation of the chemical composition, the surface sensitive synchrotron X-ray radiation techniques near edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS) as well as diffuse reflectance infrared Fourier transform spectroscopy (DRIFT) were used.

The quantification of elemental concentration in cells is usually performed by analytical assays on large populations missing peculiar but important rare cells. The present article aims at comparing the elemental quantification in single cells and cell population in three different cell types using a new approach for single cells elemental analysis performed at sub-micrometer scale combining X-ray fluorescence microscopy and atomic force microscopy. The attention is focused on the light element Mg, exploiting the opportunity to compare the single cell quantification to the cell population analysis carried out by a highly Mg-selective fluorescent chemosensor. The results show that the single cell analysis reveals the same Mg differences found in large population of the different cell strains studied. However, in one of the cell strains, single cell analysis reveals two cells with an exceptionally high intracellular Mg content compared with the other cells of the same strain. The single cell analysis allows mapping Mg and other light elements in whole cells at sub-micrometer scale. A detailed intensity correlation analysis on the two cells with the highest Mg content reveals that Mg subcellular localization correlates with oxygen in a different fashion with respect the other sister cells of the same strain.

Leaf litter plays a major role in carbon and nutrient cycling, as well as in fueling food webs. The chemical composition of a leaf may directly and indirectly influence decomposition rates by influencing rates of biological reactions and by influencing the accumulation of soil organic carbon content, respectively. This study aimed to assess the impact of the chemical composition of rubber (Hevea brasiliensis (Willd. ex A. Juss.) Muell. Arg.) leaves on various soil properties of different ages of rubber (4–5, 11–12, and 22–23 year-old). Synchrotron-based Fourier transform infrared microspectroscopy (Sr-FTIR) was utilized for analyzing the chemical composition of plant leaves. The Sr-FTIR bands illustrated that the epidermis of rubber leaves from 4–5-year-old trees was found to contain a high quantity of polysaccharides while mesophyll from 22–23-year-old trees had a large number of polysaccharides. The change in soil properties in the older rubber plantation could be attributed to its chemical composition. The change in soil properties across all tree ages, i.e., increased litter and organic carbon content, was a relatively strong driver of soil biota evolution. The aliphatic of C-H in the leaves showed high correlation with soil organic carbon (SOC) and permanganate-oxidizable C (POXC) from 22–23 year-old trees. This study shows the differences in the organic chemical composition of leaves that are consequential to soil organic carbon.

Understanding the interactions of nanomaterials （NMs） with biomolecules, organelles, cells, and organic tissues at the nano-bio interface can offer important information for their uptake, distribution, translocation, metabolism and degradation in vitro and in vivo, which can help to precisely tune and design ＂smart＂ NMs for biomedical applications. However, probing the interactions at the nano-bio interface, which generally requires dedicated analytical methods and tools, is remarkably complicated due to the dynamically changed nature of the nano-bio interface. Because of the advantages of high spatial resolution, high sensitivity, excellent accuracy, low matrix effects and non-destructiveness, synchrotron radiation （SR）-based analytical techniques have become extremely valuable tools. Herein, we present a comprehensive overview of SR-based techniques for the visualized study of NMs at cellular and subcellular interfaces and their transformation in vitro; the exploration of biodistribution, translocation, metabolism and degradation of NMs in vivo; and clarification of the molecular mechanisms of NMs＇ reactions with biomolecules. Rapid development of advanced light source means that in situ, real-time analysis of NMs at the nano-bio interface will be achieved.

The investigation of the interesting collection of the petrified wood from Bondyrz, Roztocze, south-eastern Poland, has been continued. Two kinds of microprobes such as electron microprobe from the Catholic University of Lublin and synchrotron-based X-ray microprobe from LURE, Orsay, were applied to detect the elements associated with the main component – silica and their spatial distribution and interrelations. The distribution of carbon in the petrified material has been established, which is important since that element is the main remains from the history of the trees. The carbon distribution was characteristic – it concentrated on a place of primordial dark wood. The distribution patterns of the other elements were either similar to that of carbon (Cu, Pb) or they concentrated in separate inclusions (Fe, Al, K, Na, Ca). The replicating mode of the original wood pattern in silica and carbon-containing material was explained. Some indications about the composition of the primordial petrifying solution, the rate of the petrifaction process and the recent coloration of the sample could be concluded from the compositional patterns of silica. The boundary between totally and partially petrified zones could be well observed.