Quantitative titanium imaging in fish tissues exposed to titanium dioxide nanoparticles by laser ablation-inductively coupled plasma-mass spectrometry

Imaging studies by laser ablation–inductively coupled plasma mass spectrometry have been successfully developed to obtain qualitative and quantitative information on the presence/distribution of titanium (ionic titanium and/or titanium dioxide nanoparticles) in sea bream tissues (kidney, liver, and muscle) after exposure assays with 45-nm citrate-coated titanium dioxide nanoparticles. Laboratory-produced gelatine standards containing ionic titanium were used as a calibration strategy for obtaining laser ablation–based images using quantitative (titanium concentrations) data. The best calibration strategy consisted of using gelatine-based titanium standards (from 0.1 to 2.0 μg g−1) by placing 5.0-μL drops of the liquid gelatine standards onto microscope glass sample holders. After air drying at room temperature good homogeneity of the placed drops was obtained, which led to good repeatability of measurements (calibration slope of 4.21 × 104 ± 0.39 × 104, n = 3) and good linearity (coefficient of determination higher than 0.990). Under the optimised conditions, a limit of detection of 0.087 μg g−1 titanium was assessed. This strategy allowed to locate prominent areas of titanium in the tissues as well as to quantify the bioaccumulated titanium and a better understanding of titanium dioxide nanoparticle spatial distribution in sea bream tissuesOpen Access funding provided thanks to the CRUE CSIC agreement with Springer Nature. Authors thank funding from European Union—Interreg POCTEP (ACUINANO, reference 07-12-ACUINANO_1_E); Ministerio de Economía y Competitividad (FOODNANORISK, reference PID2021-125276NB-I00); and Xunta de Galicia (Grupo de Referencia Competitiva, reference ED431C 2022/029)S

From Byssus Threads to Pinna nobilis Sea-Silk: A Fiber Chemical and Structural Characterization

Sea-silk is made from the byssus threads of Pinna nobilis, an endemic species found in the Mediterranean. The fibers are carefully harvested by cutting them off the mussel, after which they undergo a series of processes including washing, drying, combing, and spinning. The end result is an exceptionally fine, distinctive, and highly valuable fabric. Pinna nobilis byssus is non-collagenous-based, and the fiber's nanostructure is still poorly understood. In this study, we present an investigation into Pinna nobilis byssus samples collected from the Commodity Science Museum of the University of Bari Aldo Moro (Italy) at various stages of the textile manufacturing process. Through scanning electron microscopy (SEM), we reveal a distinctive elliptical cross-section of the Pinna nobilis byssus fibers. Additionally, by using wide-angle X-ray diffraction (WAXRD) and infrared (IR) spectroscopy, we discover hydroxyapatite adsorbed onto the initial fibers. This finding provides intriguing insights into the composition and potential functional properties of the byssus threads. Furthermore, using a WAXRD-based method, we observe a decrease in the crystalline/amorphous ratio during the byssus treatment process. This finding suggests the occurrence of structural modifications as the fibers undergo manufacturing steps, potentially influencing the properties of the final sea-silk fabric

Manufacturing expedients in medieval ceramics in Apulia

A group of 51 shards of medieval polychrome glazed pottery, coming from Canosa castle archaeological site (Bari, Italy), has been investigated through surface analytical techniques, such as Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDS) and elemental ones, such as Inductively Coupled PlasmaeOptical Emission Spectroscopy (ICPeOES) and Absorption Atomic Spectroscopy (AAS) by flame and electro-thermal atomisation. The investigation was aimed at defining the elemental composition of pottery findings, identifying pigments and clarifying glaze types. The results of the analytical characterization allowed the identification of materials and technological expedients used for pottery manufacturing, highlighting original features in the production of the investigated pottery. The quantitative analysis performed on ceramic paste, glaze and painted decorations provided a significant number of results, thus enabling their effective exploitation for multivariate statistical techniques, in order to find out possible groups of pottery items with defined similarity within the samples

The Tetris game of scientific investigation. Increase the score embedding analytical techniques. Raw materials and production technology of Roman glasses from Pompeii

A collection of 18 intensely coloured and variously decorated Roman glass coming from Pompeii and preserved at the National Archaeological Museum of Naples were investigated. The objects analyzed embrace a wide colour palette and several molding and decoration techniques. The analytical strategy here pursued embedded the use of optical microscopy (OM), scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDS), Raman spectroscopy and laser ablation-inductively coupled plasma-mass (LA-ICP-MS) aimed at understanding raw materials and production technology. The results achieved point out how, by means of analytical techniques sensibly integrated, archaeological questions can be solved and significant marks in know-how glass production can also be gained. The source of colours resulted in calcium antimonate (for white), lead-tin-antimony oxides (for yellow), copper (for red), iron and copper (for green), cobalt (for blue), manganese (for brown), calcium antimonate and copper/iron (for turquoise) and iron-sulphur chromophore for black/amber colour. Differently coloured parts belonging to the same object resulted made of glass of different compositions (soda-lime or lead-based). One fragment, notwithstanding the compatible glass matrix, did not seem consistent with Roman age glasses, because of the evidences (never observed before for Roman glasses) of a chrome-based raw material for green and calcium arsenate for white

Petrographic and Chemical Characterization of the Frescoes by Saturnino Gatti (Central Italy, 15th Century)

This study presents the petrographic and chemical characterization of the frescoes in the Church of San Panfilo in Tornimparte (AQ, Italy) by Saturnino Gatti, a prominent painter of the late 15th–early 16th century, known for his exquisite technique, composition, and use of color. The characterization of the frescoes is essential for understanding the materials and techniques used by Gatti, as well as for identifying the stratigraphy and painting phases. Eighteen samples were collected from the original paint layers, later additions (17th century), and restored surfaces, and analyzed by optical microscopy, cathodoluminescence microscopy, scanning electron microscopy (SEM-EDS), μ-Raman, and electron paramagnetic resonance (EPR). The analyses revealed a microstratigraphy often made of three main layers: (1) preparation, consisting of lime plaster and sand; (2) pigmented lime, applied by the fresco technique; and (3) additional pigmented layer on the surface. The most often recurring pigments are black, red, yellow (all generally linked with the fresco technique), and blue (applied “a secco”). The presence of two painting phases was also noted in one sample, probably resulting from a rethinking or restoration. These findings contribute to the understanding of the history and past restoration works of this cultural heritage site, providing important insights not only for conservators and restorers, but also for a broader understanding of Italian fresco painting and art history of the late 15th and early 16th centuries

Silver-loaded chitosan coating as an integrated approach to face titanium implant-associated infections: analytical characterization and biological activity

The present work focuses on the idea to prevent and/or inhibit the colonization of implant surfaces by microbial pathogens responsible for post-operative infections, adjusting antimicrobial properties of the implant surface prior to its insertion. An antibacterial coating based on chitosan and silver was developed by electrodeposition techniques on poly(acrylic acid)-coated titanium substrates. When a silver salt was added during the chitosan deposition step, a stable and scalable silver incorporation was achieved. The physico-chemical composition of the coating was studied by X-ray photoelectron spectroscopy (XPS), while atomic force microscopy in intermittent contact mode (ICAFM) was used to explore the coating morphology. The amount of silver released from the coating up to 21 days was evaluated by inductively coupled plasma mass spectrometry (ICP-MS). The capability of the proposed coating to interact in vitro with the biological environment in terms of compatibility and antibacterial properties was assessed using MG-63 osteoblast-like cell line and S. aureus and P. aeruginosa strains, respectively. These studies revealed that a coating showing a silver surface atomic percentage equal to 0.3% can be effectively used as antibacterial system, while providing good viability of osteoblast-like cells after 7 days. The antibacterial effectiveness of the prepared coating is mainly driven by a contact killing mechanism, although the low concentration of silver released (below 0.1 ppm up to 21 days) is enough to inhibit bacterial growth, advantaging MG-63 cells in the race for the surface