Michele Casiello

Plasma processing of liquids is a sustainable platform for green chemistry and biomedical applications, enabling the synthesis of inorganic and organic molecules without harmful reagents and with compatibility with renewable electricity. PTWS constitute reservoirs of reactive oxygen and nitrogen species, and their composition is governed not only by the experimental conditions of the plasma employed for their generation, but also, and predominantly, by the chemical composition of the precursor liquid. In this study, we demonstrate that organic solutes actively modulate RONS chemistry. Phenolic compounds such as l-tyrosine and resorcinol enhance H2O2 production while differently affecting nitrogen species, leading to either scavenging or overproduction of NO2–. Mass spectrometry reveals a strong correlation between molecular structure, plasma-induced modifications, and resulting RONS dynamics. These findings redefine PTWS as dynamic, reactive environments rather than passive reservoirs by also explaining the prolonged activity of such liquids. Beyond plasma medicine, they provide a framework for optimizing RONS-based therapies and contribute to the broader understanding of nonequilibrium chemistry in complex liquids. The results also open opportunities in water treatment and sustainable chemical transformations, positioning PTWS as versatile tools for controlling redox processes in complex aqueous systems.

Recently, choline-based ionic liquids (ILs), a class of biocompatible ILs, have been successfully employed in the pretreatment of lignocellulosic biomass. Nevertheless, their potential as solvents alternative to the more popular yet unfriendly imidazolium ILs in the oxidative depolymerization of lignin appears only marginally explored. In this study, aqueous cholinium acetate, [Ch][AcO], a readily available IL, was used as the reaction solvent for the oxidative depolymerization of Kraft lignin (KL) with H₂O₂/MoO₃. Experimental optimization design was helpful to estimate optimal reaction parameters. Under reasonably mild conditions (H₂O₂ to KL weight ratio 0.33, 9.2% MoO₃, 8% NaOH, 77 °C, 5 h), KL could be converted to 37% of depolymerization oil (KL_Oil), containing nearly 2.5% of aromatic monomers (ArMo), of which vanillin is the most abundant (up to 67%, yield 1.64%), and to 55% of oxidized lignin (OKL) solid fraction. When increasing H₂O₂/KL up to 1, ArMo yield decreased in favor of aliphatic acids (mainly, malonic acid), originating from ArMo over-oxidation, while OKL fraction enriched with carbonyl functional groups. Interestingly, in the absence of [Ch][AcO], lower ArMo yields (ArMo 1.68%) were observed, with vanillin selectivity dropping to 36% (yield 0.60%), hinting a possible stabilizing effect of the IL on reactive depolymerization intermediates and products. [Ch][AcO] could be regenerated, with <3% mass loss and unaltered chemical structure, and recycled without significant changes in product yields.

Lateral flow immunoassays (LFIAs) are widely used for point-of-care diagnostic devices due to their simplicity, low cost, and rapid results. In this work, we demonstrate that a heterosandwich design LFIA can be an effective tool for verifying the presence of different proteins on the same particles. As a case study, we address a recent controversy regarding the presence of the protein L1CAM on the extracellular vesicles (EVs). EVs are crucial for cell communication and may serve as valuable disease biomarkers, including for neurodegenerative disorders. EVs from neuronal cells can cross the blood-brain barrier and be selectively isolated from plasma. Although L1CAM has been suggested as a marker for neuron-derived EVs, recent studies report that L1CAM exists as a cleaved soluble protein in plasma, not associated with EVs. We propose a heterosandwich LFIA to detect and quantify L1CAM and a confirmed EV marker, tetraspanin CD63 or CD9, on the same EV. This assay, together with several control experiments on EVs isolated from plasma by size exclusion chromatography (SEC), demonstrates that although most L1CAM in plasma is present as soluble cleaved proteins, 13% of the EVs are strongly associated with this protein. This evidence is confirmed by dynamic light scattering measurements, showing a significant size increase of gold nanoparticles conjugated with L1CAM antibodies when exposed to EVs but not to cleaved soluble L1CAM. Our results validate the selective immune-isolation of L1CAM-EVs, resolving the controversy by confirming that L1CAM is indeed associated with a significant fraction of EVs despite the presence of its soluble form in plasma.

Water solutions treated by cold atmospheric plasmas (CAPs) currently stand out in the field of cancer treatment as sources of exogenous blends of reactive oxygen and nitrogen species (RONS). It is well known that the balance of RONS inside both eukaryotic and prokaryotic cells is directly involved in physiological as well as pathological pathways. Also, organic molecules including phenols could exert promising anticancer effects, mostly attributed to their pro-oxidant ability in vitro and in vivo to generate RONS like O₂^-, H₂O₂, and a mixture of potentially cytotoxic compounds. By our vision of combining the efficacy of plasma-produced RONS and the use of organic molecules, we could synergistically attack cancer cells; yet, so far, this combination, to the best of our knowledge, has been completely unexplored. In this study, l-tyrosine, an amino acid with a phenolic side chain, is added to a physiological solution, often used in clinical practice (SIII) to be exposed to plasma. The efficacy of the gas plasma-oxidized SIII solution, containing tyrosine, was evaluated on four cancer cell lines selected from among tumors with poor prognosis (SHSY-5Y, MCF-7, HT-29, and SW-480). The aim was to induce tumor toxicity and trigger apoptosis pathways. The results clearly indicate that the plasma-treated water solution (PTWS) reduced cell viability and oxygen uptake due to an increase in intracellular ROS levels and activation of apoptosis pathways in all investigated cancer cells, which may be related to the activation of the mitochondrial-mediated and p-JNK/caspase-3 signaling pathways. This research offers improved knowledge about the physiological mechanisms underlying cancer treatment and a valid method to set up a prompt, adequate, and effective cancer treatment in the clinic.

Agronomic practices and the winemaking process lead to the production of considerable quantities of waste and by-products. These are often considered waste with negative effects on environmental sustainability. However, vine shoots and grape stalks can be reused, representing a potential source of xylo-oligosaccharides and polyphenols. In this context, the purpose of this work was to obtain enriched extracts using three different autohydrolysis treatments with (i) H₂O, (ii) H₂O:EtOH, and (iii) H₂O:Amberlyst. The obtained extracts were characterized by their xylo-oligosaccharide and polyphenol profiles using LC-MS techniques. The use of ethanol during autohydrolysis allowed for greater extraction of xylan-class compounds, especially in vine shoot samples, while an increase in antioxidant activity (128.04 and 425.66 µmol TE/g for ABTS and DPPH, respectively) and in total phenol content (90.92 mg GAE/g) was obtained for grape stalks.

The total amount of cellulose from paper, wood, food, and other human activity waste produced in the EU is in the order of 900 million tons per year. This resource represents a sizable opportunity to produce renewable chemicals and energy. This paper reports, unprecedently in the literature, the usage of four different urban wastes such as cigarette butts, sanitary pant diapers, newspapers, and soybean peels as cellulose fonts to produce valuable industrial intermediates such as levulinic acid (LA), 5-acetoxymethyl-2-furaldehyde (AMF), 5-(hydroxymethyl)furfural (HMF), and furfural. The process is accomplished by the hydrothermal treatment of cellulosic waste using both Brønsted and Lewis acid catalysts such as CH₃COOH (2.5–5.7 M), H₃PO₄ (15%), and Sc(OTf)₃ (20% w:w), thus obtaining HMF (22%), AMF (38%), LA (25–46%), and furfural (22%) with good selectivity and under relatively mild conditions (T = 200 °C, time = 2 h). These final products can be employed in several chemical sectors, for example, as solvents, fuels, and for new materials as a monomer precursor. The characterization of matrices was accomplished by FTIR and LCSM analyses, demonstrating the influence of morphology on reactivity. The low e-factor values and the easy scale up render this protocol suitable for industrial applications.

The adhesive manufacturing industry needs more eco-sustainable processes. In this regard, the main road is to replace raw fossil materials with renewable resources or waste biomass, and simultaneously improve synthetic steps by using clean and greener reagents under mild conditions. In this paper, a synthetic pathway for producing biobased succinyl peroxide (SP) from waste biomass is reported, and then the application range of this polymerization agent to methacrylates and styrene-free resins is extended. At the same time, new formulations of pastes based on benzoyl or succinyl peroxide, displaying an almost complete biobased carbon content, are investigated and tested as cross-linking agents for mastic marble and unsaturated polyester resins. Physicochemical characterization of the final products and polymers is carried out with thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR), Gel Permeation Chromatography (GPC), Nuclear Magnetic Resonance (NMR) and peak exothermic curve analyses.