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Four highly bioactive glasses in a binary SiO2–CaO system are prepared following a sol−gel method using Ca(OH)2 as a calcium precursor. In the synthesis of glass according to the modified Stöber method, Ca(OH)2 suspended in polyethylene glycol allows the elimination of the presence of calcite and the increase of ammonia concentration causes formation of spherical particles with different sizes in the range of 26–266 nm. The relation among the size and properties, including bioactivity, of the glass particles is evaluated. New glasses that vary in composition (10–25 wt% CaO), porosity (15–113 m2 g−1), and hydroxyl groups content greatly enhance the formation process of hydroxyapatite (HA) in simulated physiological fluids. For all glasses, superior apatite‐mineralization ability in time as short as 2 h in the physiological‐like buffer is achieved, thus exceeding the bioactivity of the known bioactive glasses, including 45S5 glass (Bioglass). The assessment of the safety and toxicity profile of the obtained glasses is verified in a wide range of concentrations (1–1000 µg mL−1) against human dermal fibroblasts and MC3T3 mouse osteoblast precursors, but also to human erythrocytes by determining hemocompatibility. Two glasses of different sizes, 73 and 266 nm, are promising and warrant further research. [ABSTRACT FROM AUTHOR]

A binary and ternary system of highly bioactive nanoparticles of xerogel (88SiO 2 –12CaO (wt.%), solvXG88, 78SiO 2 –16CaO–6P 2 O 5 , solvXG78P6) and glass (69SiO 2 –25CaO–6P 2 O 5, solvBG69P6) were prepared following an unconventional solvothermal path of the synthesis. These nanosized (<50 nm), non-spherical in shape and mesoporous materials with different compositions greatly enhanced the formation process of hydroxyapatite (HA) in simulated physiological fluids compared to reference 45S5 glass, commonly used in orthopedics and dentistry. The deposition of a HA layer on the glasses was analyzed by various techniques, namely XRD, IR-ATR, 31P CP-MAS NMR, EDS analyses, SEM, and HR-TEM imaging. For both types of nanoparticles (glass and obtained at lower temperature xerogels) superior apatite-mineralization ability in time as short as 4 h in the physiological-like buffer was achieved thus, exceeded the bioactivity of the 45S5 glass. This unique bioactivity was complemented by biocompatibility with human dermal fibroblasts and MC3T3 mouse osteoblast precursors, verified in a wide range of concentrations, as well as hemocompatibility studies. The most promising candidate which can compete with clinically used Bioglass is solvXG78P6. [Display omitted] [ABSTRACT FROM AUTHOR]

Ascorbic acid (AA) is an important biomolecule, the deficiency or maladjustment of which is associated with the symptoms of many diseases (e.g., cardiovascular disease or cancer). Therefore, there is a need to develop a fluorescent probe capable of detecting AA in aqueous media. Here, we report the synthesis, structural, and spectroscopic characterization (by means of, e.g., XRD, XPS, IR and Raman spectroscopy, TG, SEM, and EDS analyses), as well as the photoluminescent properties of a metal–organic framework (MOF) based on Cu2+ and Eu3+ ions. The ion-exchange process of the extraframework cation in anionic Cu-based MOF is proposed as an appropriate strategy to obtain a new material with a nondisturbed structure and a sensitivity to interaction with AA. Accordingly, a novel Eu[Cu3(μ3-OH)(μ3-4-carboxypyrazolato)3] compound for the selective optical detection of AA with a short detection time of 5 min is described. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two types of nanoglass based on SiO 2 –CaO and SiO 2 –CaO–ZnO systems prepared by a sol–gel method. • Effect of ZnO doping on the antibacterial activity of glass against Staphyloccocus aureus. • Impact of high ZnO content (17 wt.%) on reduced bioactivity of glass. • Biocompatibility of glasses confirmed against HDF and MC3T3 cells. • Synergistic adsorption–photocatalytic degradation effect on methylene blue. In this study, two spherical nanoglasses based on the binary 83SiO 2 –17CaO (wt.%) (BG) and ternary 75SiO 2 –8CaO–17ZnO (BG-ZnO) systems were prepared following a sol–gel method. Changes in the structure, morphology and composition of the glasses after immersion in the buffer that simulates physiological conditions (DPBS) were analyzed by various techniques, namely XRD, IR-ATR, EDS analyses, SEM, and TEM imaging. The obtained results were compared to the 45S5 glass tested as a reference biomaterial. The formation of the hydroxyapatite (HA) layer on the BG started from the first hours of incubation in the buffer, while the presence of ZnO inhibited the formation of HA. Instead, the dissolution of BG-ZnO led to the formation of [Na 6 (ZnPO 4) 6 (H 2 O) 8 ]. Nevertheless, the intention of increasing the functionality of glasses doped with ZnO was achieved since biocompatible BG-ZnO exhibited antibacterial properties against Staphyloccocus aureus. Moreover, the material demonstrated the synergistic adsorption–photocatalytic degradation effect on common target pollutants such as methylene blue. [ABSTRACT FROM AUTHOR]

This work investigates the sorption properties of poly(divinylbenzene) modified in the Diels–Alder reaction towards persistent and mobile metabolites of terbuthylazine. The batch experiments were carried out to examine the efficiency of desethyl-terbuthylazine and 2-hydroxy-terbuthylazine adsorption on the specific adsorbent and the impact of different factors on the adsorption process. Results fit well to a pseudo-second order kinetic model. It was confirmed that hydrogen bonds play an important role in the studied systems. Five times greater sorption of 2-hydroxy-terbuthylazine than desethyl-terbuthylazine was observed. The molecular structures of both metabolites exhibit complementarity to the arrangement of functional groups in the polymer but the differences in the physicochemical properties of the desethyl derivative make it a highly mobile compound with higher affinity to the aqueous phase. The equilibrium data in the batch study fit the Freundlich isotherm for 2-hydroxy-terbuthylazine, and for desethyl-terbuthylazine the Temkin and Dubinin–Radushkevich models were better. The adsorption capacities obtained under dynamic conditions were comparable with batch results. For column adsorption modeling the Bohart–Adams, Wolborska, Thomas and Yoon–Nelson models were used. The proposed microspheres can be reused easily with no significant decrease in adsorption capacity by using ethanol as eluent in the desorption. [ABSTRACT FROM AUTHOR]