The development of nanotools for chemical sensing and macromolecular modifications is a new challenge in the biomedical field, with emphasis on artificial peptidases designed to cleave peptide bonds at specific sites. In this landscape, metal porphyrins are attractive due to their ability to form stable complexes with amino acids and to generate reactive oxygen species when irradiated by light of appropriate wavelengths. The issues of hydrophobic behavior and aggregation in aqueous environments of porphyrins can be solved by using its PEGylated derivatives.
View Article and Find Full Text PDFThe study reports the use of nanoassembly based on cationic cyclodextrin carbon nanotubes (CNT-CDs) and ferrocenylcarnosine (FcCAR) for electrochemical sensing of Hg(II) in aqueous solution. β-cyclodextrins (CDs) were grafted onto CNTs by a click chemistry reaction between heptakis-(6-azido-6-deoxy)-β-cyclodextrin and alkyne-terminated CNTs. The cationic amine groups on the CD units were produced by the subsequent reduction of the residual nitrogen groups.
View Article and Find Full Text PDFIn this study, two boronic acid BODIPYs are obtained through a microwave-assisted Knoevenagel reaction. The aim is to use them for the first time as dyes in a photosensitized solar cell (DSSC) to mimic chlorophyll photosynthesis, harvesting solar light and converting it into electricity. The microwave-assisted Knoevenagel reaction is a straightforward approach to extending the molecular conjugation of the dye and is applied for the first time to synthesize BODIPY's boronic acid derivatives.
View Article and Find Full Text PDFSpace exploration missions are currently becoming more frequent, due to the ambition for space colonization in sight of strengthening terrestrial technologies and extracting new raw materials and/or resources. In this field, the study of the materials' behaviour when exposed to space conditions is fundamental for enabling the use of currently existing materials or the development of new materials suitable for application in extra-terrestrial environments. In particular, the versatility of polymers renders them suitable for advanced applications, but the effects of space radiation on these materials are not yet fully understood.
View Article and Find Full Text PDFPolycyclic aromatic hydrocarbons (PAHs) are the most widespread xenobiotic pollutants in water and their abatement usually involves expensive and energy-consuming treatments. In this work, anthracene (AN) was selected as the recalcitrant model of PAHs and its solar light-stimulated heterogeneous photocatalytic abatement in aerated aqueous media was investigated using a new TiO derived thermoplastic nanocomposite in thin film form. The results were also compared with the benchmark TiO photocatalyst in slurry form.
View Article and Find Full Text PDFAmong different depollution methods, photocatalysis activated by solar light is promising for terrestrial outdoor applications. However, its use in underground structures and/or microgravity environments (e.g.
View Article and Find Full Text PDFRecognition and capture of amyloid beta (Aβ) is a challenging task for the early diagnosis of neurodegenerative disorders, such as Alzheimer's disease. Here, we report a novel KLVFF-modified nanomagnet based on magnetic nanoparticles (MNP) covered with a non-ionic amphiphilic β-cyclodextrin (SC16OH) and decorated with KLVFF oligopeptide for the self-recognition of the homologous amino-acids sequence of Aβ to collect Aβ (1-42) peptide from aqueous samples. MNP@SC16OH and MNP@SC16OH/Ada-Pep nanoassemblies were fully characterized by complementary techniques both as solid powders and in aqueous dispersions.
View Article and Find Full Text PDFMünchnones are mesoionic oxazolium 5-oxides with azomethine ylide characteristics that provide pyrrole derivatives by a 1,3-dipolar cycloaddition (1,3-DC) reaction with acetylenic dipolarophiles. Their reactivity was widely exploited for the synthesis of small molecules, but it was not yet investigated for the functionalization of graphene-based materials. Herein, we report our results on the preparation of münchnone functionalized graphene via cycloaddition reactions, followed by the spontaneous loss of carbon dioxide and its further chemical modification to silver/nisin nanocomposites to confer biological properties.
View Article and Find Full Text PDFThe Spontaneous Symmetry Breaking (SSB) phenomenon is a natural event in which a system changes its symmetric state, apparently reasonless, in an asymmetrical one. Nevertheless, this occurrence could be hiding unknown inductive forces. An intriguing investigation pathway uses supramolecular aggregates of suitable achiral porphyrins, useful to mimic the natural light-harvesting systems (as chlorophyll).
View Article and Find Full Text PDFSilver nanoparticles (AgNPs) stand out over other metal nanoparticles thanks to their peculiar bactericidal and spectroscopic properties. Tunability of the AgNPs chemical-physical properties could be provided through their organic covalent coating. On the other hand, PEGylated porphyrin derivatives are versatile heteromacrocycles investigated for uses in the biomedical field as cytotoxic and tracking agents, but also as sensors.
View Article and Find Full Text PDFA new porous material based on the first supramolecular cucurbituril-based nanosponge was synthesized by the functionalization of cucurbit[6]uril with twelve 1-(2-bromoethyl)-3-methyl-1H-imidazol-3-ium arms. The porous structure and the high adsorption capacity were demonstrated through surface area measurements and carbon dioxide adsorption. The new supramolecular sponge showed attractive properties such as (i) a highly porous structure that allowed CO capture, (ii) the possibility to reuse the adsorbed CO for organic synthesis, and (iii) an exciting thermal stability up to around 800 °C, with the potential use of this material in high temperature reactions.
View Article and Find Full Text PDFPhotocatalytic remediation represents a potential sustainable solution to the abatement of xenobiotic pollutants released within the water environment. Aeroxide P25 titanium dioxide nanoparticles (TiO NPs) are well-known as one of the most efficient photocatalysts in several applications, and have also been investigated in water remediation as suspended powder. Recently, their application in the form of thin films has been revealed as a potential alternative to avoid time-consuming filtration processes.
View Article and Find Full Text PDFMater Sci Eng C Mater Biol Appl
December 2020
We report the synthesis, characterization and biological profile of new bis-triazoled cyclopolylactides (c-PLA, c-PLA-FA, c-PLA-Rhod) obtained by an optimized combination of ROP and click chemistry reactions. Cyclo-PLA having a number average molecular weight of 6000 g mol and a polydispersity index of 1.52 was synthetized by click ring-closure of well-defined α,ω-heterodifunctional linear precursors, followed by quaternarization of N-triazole nodes, and subsequent CuAAC with azido-folate and azido-rhodamine yielding jellyfish-shaped c-PLA-FA and c-PLA-Rhod.
View Article and Find Full Text PDFThe main objective of supramolecular chemistry is to mimic the macrosystems present in nature, a goal that fits perfectly with the green chemistry guidelines. The aim of our work is to use the hydrophobic cavity of cucurbit[7]uril (CB[7]) to mimic nature for performing different dehydration and cycloaddition reactions in water. The hydrophobic cavity of CB[7] made it possible to synthesize nitrones and isoxazolidines in a one-pot fashion using water as a reaction solvent.
View Article and Find Full Text PDFThe theranostic ability of a new fluorescently labeled cationic cyclodextrin-graphene nanoplatform (GCD@Ada-Rhod) was investigated by studying its intracellular trafficking and its ability to deliver plasmid DNA and microRNA. The nanoplatform was synthesized by both covalent and supramolecular approaches, and its chemical structure, morphology, and colloidal behavior were investigated by TGA, TEM, spectroscopic analysis such as UV-vis, fluorescence emission, DLS, and ζ-potential measurements. The cellular internalization of GCD@Ada-Rhod and its perinuclear localization were assessed by FLIM, Raman imaging, and fluorescence microscopy.
View Article and Find Full Text PDFThe development of graphene (G) substrates without damage on the sp network allows to tune the interactions with plasmonic noble metal surfaces to finally enhance surface enhanced Raman spectroscopy (SERS) effect. Here, we describe a new graphene/gold nanocomposite obtained by loading gold nanoparticles (Au NPs), produced by pulsed laser ablation in liquids (PLAL), on a new nitrogen-doped graphene platform (G-NH). The graphene platform was synthesized by direct delamination and chemical functionalization of graphite flakes with 4-methyl-2--nitrophenyl oxazolone, followed by reduction of -nitrophenyl groups.
View Article and Find Full Text PDFThe potential of pyrene-1-sulfonate to act as an emitting anion for the development of ionic liquids is explored here. Amphiphilic trimethylpropylammonium hepta(isooctyl)octasilsesquioxane and conventional imidazolium, namely, 1-vinyl-3-hexyl-, 1-vinyl-3-decyl-, and 1-methyl-3-decyl-imidazolium, featuring moderate alkyl chain length substituents, have been chosen as countercations. The new species have been synthesized via simple metathesis reactions involving pyrene-1-sulfonate sodium salt and the appropriate halide cation precursors.
View Article and Find Full Text PDFWe report on new Zn-Salen oligomer receptors able to recognize a nerve agent simulant, namely dimethyl methylphosphonate (DMMP), by a supramolecular approach. In particular, three Zn-Salen oligomers (Zn-Oligo-A, -B, and -C), differing by the length distribution, were obtained and characterized by NMR, Gel Permeation Chromatography (GPC), UV-Vis, and fluorescence spectroscopy. Furthermore, we investigated their recognition properties towards DMMP by using fluorescence measurements.
View Article and Find Full Text PDFJ Biomed Mater Res B Appl Biomater
November 2018
Pentamidine (Pent), an antiparasitic drug used for the treatment of visceral leishmaniasis, has been modified with terminal azide groups and conjugated to two different polymer backbones (PLGA-PEG [PP] copolymer and hyaluronic acid [HA]) armed with alkyne end-groups. The conjugation has been performed by Copper Catalyzed Azido Alkyne Cycloaddition (CuAAC) using CuSO /sodium ascorbate as metal source. The novel PP-Pent and HA-Pent bioconjugates are proposed, respectively, as non-targeted and targeted drug delivery systems against Leishmania infections.
View Article and Find Full Text PDF((3RS,5SR)- and ((3RS,5RS)-2-(2-methoxybenzyl)-3-(1,10-phenanthrolin-2-yl)isoxazolidin-5-yl)methanol have been synthesized, according to 1,3-dipolar cycloaddition methodology, as DNA intercalating agents and evaluated for their anticancer activity against human cervical carcinoma HeLa and head and neck squamous cells carcinoma cell lines. The synthesized compounds exhibited good cytotoxic activity with IC better than cisplatin, used as the main and effective treatment for HNSCC, and a 24.3-72.
View Article and Find Full Text PDFSolvent-free 1,3-dipolar cycloaddition (1,3-DC) reactions between graphite flakes and mesoionic oxazolones were carried out by heating the resulting solid mixture at mild temperatures (70-120 °C). The direct functionalization and delamination of graphite flakes into few layers of graphene nanosheets was confirmed by micro-Raman and X-ray photoelectron spectroscopies, scanning transmission electron microscopy and thermogravimetric analysis. The 1,3-DC reactions of mesoionic dipoles have been investigated with density functional theory to model graphene, exploring three different pathways: center, corner and edge.
View Article and Find Full Text PDFGlycerol is an effective carbon source for the production of scl- and mcl-polyhydroxyalkanoates (PHAs) by Pseudomonas spp. P. mediterranea 9.
View Article and Find Full Text PDFOptical detection of parts-per-million (ppm) levels of CO by a structurally well-defined monolayer consisting of bimetallic rhodium complexes on glass substrates has been demonstrated.
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