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111.
Riccardo Barbari Chiara Tupini Elisa Durini Eleonora Gallerani Francesco Nicoli Ilaria Lampronti Anna Baldisserotto Stefano Manfredini 《Molecules (Basel, Switzerland)》2023,28(1)
A current trend of research in the health field is toward the discovery of multifunctional compounds, capable of interacting with multiple biological targets, thus simplifying multidrug therapies and improving patient compliance. The aim of this work was to synthesize new multifunctional chemical entities bearing a benzothiazole nucleus, a structure that has attracted increasing interest for the great variety of biological actions that it can perform, and already used as a scaffold in several multifunctional drugs. Compounds are reported, divided into two distinct series, synthetized and tested in vitro for the antioxidant, and include UV-filtering and antitumor activities. DPPH and FRAP tests were chosen to outline an antioxidant activity profile against different radical species. The UV-filtering activity was investigated, pre- and post-irradiation, through evaluation of a O/W sunscreen standard formulation containing 3% of the synthetic compounds. The antitumor activity was investigated both on human melanoma cells (Colo-38) and on immortalized human keratinocytes as a control (HaCat). A good antiproliferative profile in terms of IC50 was chosen as a mandatory condition to further investigate apoptosis induction as a possible cytotoxicity mechanism through the Annexin V test. Compound BZTcin4 was endowed with excellent activity and a selectivity profile towards Colo-38, supported by a good antioxidant capacity and an excellent broad-spectrum photoprotective profile. 相似文献
112.
Dr. Maria Laura Tummino Dr. Roberto Nisticò Dr. Chiara Riedo Prof. Debora Fabbri Prof. Marta Cerruti Prof. Giuliana Magnacca 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(2):660-668
Biowaste-derived substances isolated from green compost (BBS-GC) are environmentally friendly reactants similar to humic substances, which contain multiple functionalities, that are suitable for adsorbing different kinds of pollutants in wastewater. Herein, sodium alginate (derived from brown algae) cross-linked with both Ca2+ ions and BBS-GC in the form of hydrogels and dried films are proposed as green, easy-to-form, and handleable materials for tertiary water treatments. The results show that both hydrogels and films are mechanically stable and can effectively remove differently charged dyes through an adsorption mechanism that can be described by the Freundlich model. BBS-GC-containing gels always performed better than samples prepared without BBS-GC, revealing that such unconventional materials can integrate waste valorization and water decontamination, potentially providing social and environmental benefits. 相似文献
113.
Chiara Capolungo Dr. Damiano Genovese Prof. Marco Montalti Prof. Enrico Rampazzo Prof. Nelsi Zaccheroni Prof. Luca Prodi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(70):17529-17541
The growing numbers related to plastic pollution are impressive, with ca. 70 % of produced plastic (>350 tonnes/year) being indiscriminately wasted in the environment. The most dangerous forms of plastic pollution for biota and human health are micro- and nano-plastics (MNPs), which are ubiquitous and more bioavailable. Their elimination is extremely difficult, but the first challenge is their detection since existing protocols are unsatisfactory for microplastics and mostly absent for nanoplastics. After a discussion of the state of the art for MNPs detection, we specifically revise the techniques based on photoluminescence that represent very promising solutions for this problem. In this context, Nile Red staining is the most used strategy and we show here its pros and limitations, but we also discuss other more recent approaches, such as the use of fluorogenic probes based on perylene-bisimide and on fluorogenic hyaluronan nanogels, with the added values of biocompatibility and water solubility. 相似文献
114.
Davide Barreca Ettore Fois Alberto Gasparotto Chiara Maccato Mario Oriani Gloria Tabacchi 《Molecules (Basel, Switzerland)》2021,26(7)
Transition metal complexes with β-diketonate and diamine ligands are valuable precursors for chemical vapor deposition (CVD) of metal oxide nanomaterials, but the metal-ligand bond dissociation mechanism on the growth surface is not yet clarified in detail. We address this question by density functional theory (DFT) and ab initio molecular dynamics (AIMD) in combination with the Blue Moon (BM) statistical sampling approach. AIMD simulations of the Zn β-diketonate-diamine complex Zn(hfa)2TMEDA (hfa = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate; TMEDA = N,N,N′,N′-tetramethylethylenediamine), an amenable precursor for the CVD of ZnO nanosystems, show that rolling diffusion of this precursor at 500 K on a hydroxylated silica slab leads to an octahedral-to-square pyramidal rearrangement of its molecular geometry. The free energy profile of the octahedral-to-square pyramidal conversion indicates that the process barrier (5.8 kcal/mol) is of the order of magnitude of the thermal energy at the operating temperature. The formation of hydrogen bonds with surface hydroxyl groups plays a key role in aiding the dissociation of a Zn-O bond. In the square-pyramidal complex, the Zn center has a free coordination position, which might promote the interaction with incoming reagents on the deposition surface. These results provide a valuable atomistic insight on the molecule-to-material conversion process which, in perspective, might help to tailor by design the first nucleation stages of the target ZnO-based nanostructures. 相似文献
115.
Jose Gracia Mauro Fianchini Chiara Biz Victor Polo Roberto Gómez 《Current Opinion in Electrochemistry》2021
Strongly correlated catalysts can be understood from precise quantum approximations. Incorporating properly electronic correlations thus let’s define Spin rules in catalysis, opening a new door towards optimum compositions for the most important reactions for a sustainable future. 相似文献
116.
117.
Stefania?Gaudino Chiara?Galas Maria?Belli Sabrina?Barbizzi Paolo?de?Zorzi Radojko?Ja?imovi? Zvonka?Jeran Alessandra?Pati Umberto?SansoneEmail author 《Accreditation and quality assurance》2007,12(2):84-93
The measurement of trace-element concentration in soil, sediment and waste, is generally a combination of a digestion procedure
for dissolution of elements and a subsequent measurement of the dissolved elements. “Partial” and “total” digestion methods
can be used in environmental monitoring activities. To compare measurement results obtained by different methods, it is crucial
to determine and to maintain control of the bias of the results obtained by these methods. In this paper, ICP-MS results obtained
after matrix digestion with modified aqua regia (HCl+HNO3+H2O2) method and two “total” digestion methods (microwave aqua regia+HF and HNO3+HF) are compared with those obtained by instrumental neutron activation analysis, a non-destructive analytical method for
the determination of the total mass concentrations of inorganic components in environmental matrices. The comparison was carried
out on eight agricultural soil samples collected in one test area and measured by k0-INAA and ICP-MS to determine As, Co, Cr, Sb and Zn mass concentration. The bias of results for As, Cd, Co, Cr, Cu, Ni, Pb,
Sb and Zn of the three digestion methods were assessed using selected measurement standards. This paper highlights that the
digestion procedure is an integral part of the measurement and can affect the measurement result in environmental analysis. 相似文献
118.
Prof. Gianlorenzo Bussetti Claudia Filoni Prof. Andrea Li Bassi Dr. Alberto Bossi Prof. Marcello Campione Prof. Alessio Orbelli Biroli Prof. Chiara Castiglioni Dr. Silvia Trabattoni Dr. Stefania De Rosa Prof. Luca Tortora Prof. Franco Ciccacci Prof. Lamberto Duò 《ChemistryOpen》2021,10(8):748-755
We have recently discussed how organic nanocrystal dissolution appears in different morphologies and the role of the solution pH in the crystal detriment process. We also highlighted the role of the local molecular chemistry in porphyrin nanocrystals having comparable structures: in water-based acid solutions, protonation of free-base porphyrin molecules is the driving force for crystal dissolution, whereas metal (ZnII) porphyrin nanocrystals remain unperturbed. However, all porphyrin types, having an electron rich π-structure, can be electrochemically oxidized. In this scenario, a key question is: does electrochemistry represent a viable strategy to drive the dissolution of both free-base and metal porphyrin nanocrystals? In this work, by exploiting electrochemical atomic force microscopy (EC-AFM), we monitor in situ and in real time the dissolution of both free-base and metal porphyrin nanocrystals, as soon as molecules reach the oxidation potential, showing different regimes according to the applied EC potential. 相似文献
119.
Cavaliere C Foglia P Pastorini E Samperi R Laganà A 《Rapid communications in mass spectrometry : RCM》2005,19(21):3143-3158
A mass spectrometric method for extensive detection and semi-quantitative determination of flavonoid glycosides in stem and leaves of young Triticum durum plants is presented. About 100 g of sample were lyophilized and ground, and the compounds of interest were then extracted, cleaned-up, and fractionated using high-performance liquid chromatography (HPLC). Tandem mass spectrometry analyses were performed using a quadrupole-linear ion trap instrument with an information-dependent data acquisition (IDA) protocol that looped two experiments, enhanced MS scan and enhanced product ion scan. Various glycoconjugates, which are all derivatives of only four flavones, apigenin, luteolin, chrysoeriol and tricin, were identified and belong to the following categories: 7 monoglycosides, 31 diglycosides, 15 triglycosides and 1 tetraglycoside. Among these some acylated glycosides were found. Tricin derivatives are present exclusively as O-glycosides, while apigenin and luteolin are present always as C-glycosides. Semi-quantitative estimation was performed by using the monoglycoside and diglycoside of quercetin as internal standards. 相似文献
120.
Realini M Colombo C Sansonetti A Rampazzi L Colombini MP Bonaduce I Zanardini E Abbruscato P 《Annali di chimica》2005,95(3-4):217-226
The analytical studies carried out during two different diagnostic surveys, respectively in 1983 and 2003, offered the opportunity to control decay phenomena development on stones facing Certosa of Pavia (Italy). Calcium oxalate films and red stains, present on Carrara marble surface, have been particularly focused; these are the only decay phenomena which apparently have remained unchanged during a period of twenty years. More sensitive and in-depth analytical studies (FTIR equipped with diamond cell, GC-MS, SEM-EDS and optical microscopy) achieved a better knowledge about their composition. Results allowed a critical evaluation of the role of oxalate films on the external marble surface and to suggest new hypotheses about the formation of red stains. 相似文献