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Drugs delivered by proper carriers enter into the cells much more rapidly and carry out their action much more promptly than in the free forms. A high drug concentration can be sustained for longer periods of time at the target site in the cell. In in vivo conditions, this would translate into a reduction of systemic toxicity, dosage and frequency of dosing. Dendritic polymers significantly affect drug delivery in terms of reaching the target site, modifying the bio-distribution of the drug, and enhancing the efficacy of different drugs including anticancer compounds. 2-({[2-({[(2-tolyl)amino]carbonothioyl}oxy)ethyl]amino}carbo-nyl)benzoic acid 1 is a thiocarbamate derivative belonging to an already reported class of non-nucleoside HIV-1 reverse transcriptase inhibitors. In in vitro assay it showed no cytotoxic effects but was endowed with very low solubility and poor activity against wild-type HIV-1 (EC50 = 27 μM). With the aim at improving its water solubility, 1 has been successfully incorporated inside non-toxic amino acids-modified core-shell hetero dendrimers. IR, NMR, zeta potential, mean size of particles, buffer capacity and in vitro release profile of prepared materials were reported. All dendriplexes were evaluated in cell-based assays to assess their cytotoxic profile. The obtained complexes, which harmonize a peripheral polycationic character and a buffer capacity which presuppose efficient cells penetration and increased residence time with a not PAMAM structured biodegradable scaffold, were well water-soluble and could rationally appear as a promising set of prodrugs for safe in vivo administrations.

Dendrimers are macromolecules characterized by high controlled size, shape and architecture, presence of inner cavities able to accommodate small molecules and many peripheral functional groups to bind target entities. They are of eminent interest for biomedical applications, including gene transfection, tissue engineering, imaging, and drug delivery. The well-known pharmacological activities of ursolic and oleanolic acids are limited by their small water solubility, non-specific cell distribution, low bioavailability, poor pharmacokinetics, and their direct administration could result in the release of thrombi. To overcome such problems, in this paper we described their physical incorporation inside amino acids-modified polyester-based dendrimers which made them highly water-soluble. IR, NMR, zeta potential, mean size of particles, buffer capacity and drug release profiles of prepared materials were reported. The achieved water-soluble complexes harmonize a polycationic character and a buffer capacity which presuppose efficient cell penetration and increased residence time with a biodegradable cell respectful scaffold, thus appearing as a promising team of not toxic prodrugs for safe administration of ursolic and oleanolic acids.

International audience; Oryza sativa L. 'Violet Nori' is an Italian cultivar of spontaneous growing aromatic purple rice which is particularly rich in polyphenolic compounds, especially anthocyanins, conferring it an excellent antioxidant capacity. The present study aimed at increasing the extraction yields of its antioxidant compounds with green strategies and it is divided into two steps. The first step concerned a solubility study of the targeted polyphenols in different ethanol:water mixtures by means of a theoretical prediction method, using the simulation program COSMO-RS, and the subsequently confirmation of the computational results by practical experiments. Once the best extraction mixture was identified, the second step of the work was performed, with the purpose of intensifying the extraction yield. Therefore, various innovative green extraction techniques, including ultrasound, using both the probe system and the ultrasonic bath, bead milling, microwave and accelerated solvent extractions were tested and compared to conventional maceration.Results, expressed in terms of total phenolic and total monomeric anthocyanin contents, showed that the best extracting solvent for 'Violet Nori' rice was the mixture ethanol:water (60:40 v/v), being COSMO-RS computational predictions in good correlation with the experimental results. Moreover, the most efficient techniques to extract the antioxidant compounds resulted to be both ultrasound-assisted extraction probe and bead milling, that in only 5 min got the same extractive efficiency obtained after 3 h of conventional maceration.

It is well known that several polycyclic aromatic hydrocarbons (PAHs), products of incomplete pyrolysis of organic material, have proved to be extremely toxic to humans. Food can be contaminated by these compounds in many different ways and diet represents nowadays the major source of exposure to PAHs for non-smokers population. In the present study, three of the most important carcinogenic PAHs in foods, according to the legislation currently in force, i.e. benzo[a]pyrene (BaP), benzo[a]anthracene (BaA) and chrysene (Chry), were firstly arranged in ternary mixtures, following an experimental design. Then, an organic extraction from a commercial smoked tuna, potentially affected by PAHs, was performed to investigate the presence of the three compounds under study. A spectrofluorimetric method based on the second order calibration of excitation-emission fluorescence matrices (EEMs) and parallel factor analysis (PARAFAC) decomposition was proposed in this work as analytical approach for PAHs detection. Both in the ternary mixtures and in the food matrix (smoked tuna), PAHs were unequivocally identified and quantified with decision limit (CCα) and capability of detection (CCβ) equal to 0.11 µg L−1 and 0.21 µg L−1 for BaP, 0.27 µg L−1 and 0.53 µg L−1 for BaA and 0.18 µg L−1 and 0.35 µg L−1 for Chry, respectively, when the probabilities of false positive (α) and false negative (β) were fixed at 0.05. In the investigated smoked tuna, detectable levels of BaP were found, whereas BaA and Chry were absent., MINECO (AEI/FEDER, UE) and Junta de Castilla y León through projects CTQ2017-88,894-R and BU012P17 respectively (all co-financed with FEDER funds).

Ellagic acid (EA) is a bioactive natural polyphenol with antioxidant and several other beneficial properties, but unfortunately it cannot be exploited for in vivo therapeutic applications because of its poor water solubility and accordingly low bioavailability. Aiming to increase EA solubility, an EA solid microdispersion was realized by employing only water and low methoxylated pectin as a food compatible excipient by applying spray drying technology. It showed a 22% (w/w) Drug Loading (DL), a 30 times improved water solubility and remarkable radical scavenging activity. Subsequently, adopting non-PAMAM hydrophilic and amphiphilic dendrimers as nanocontainers, two EA nanodispersions were achieved (60–70 nm) with 46 and 53% (w/w) DL, water solubility 300 to 1000 times higher than that of free EA and good antioxidant capability. In both cases, toxic agents such as castor oil, Tween 80 or the extensively used but not so safe PEG400 were avoided and no previously used carriers, including β-cyclodextrins, were adopted. The prepared micro- and nanodispersions showed water solubility never obtained before and represent non-toxic EA reservoirs suitable for food and biomedical applications.