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In this work, the electrochemical behavior of the glycosylated flavonoid kaempferitrin was studied, and an electroanalytical methodology was developed for its determination in infusions of Bauhinia forficata using a boron-doped diamond electrode (BDD). The electrochemical behavior of the flavonoid was studied by cyclic voltammetry, and two irreversible oxidation peaks at 0.80 and 1.0 V vs Ag/AgCl were observed. The influence of the pH on the voltammograms was examined, and higher sensitivity was found at pH 7.0. The electrochemical process corresponding to peak 1 at 0.80 V is predominantly diffusion-controlled, as the study shows at varying scan rates. An analytical plot was obtained by square wave voltammetry at optimized experimental conditions (frequency = 100 s -1 , amplitude = 90 mV, and step potential = 8 mV) in the concentration range from 3.4 μmol L -1 to 58 μmol L -1 , with a linearity of 0.99. The limit of detection and limit of quantification values were 1.0 μmol L -1 and 3.4 μmol L -1 , respectively. Three samples of Bauhinia forficata infusions (2 g of sample in 100 mL of water) were analyzed, and the KF values found were 5.0 × 10 -4  mol L -1 , 3.0 × 10 -4  mol L -1 , and 7.0 × 10 -4  mol L -1 , with recovery percentages of 98 %, 106 % and 94 %, respectively. Finally, experiments were performed with two other flavonoids (chrysin and apeginin) to compare and propose an electrochemical oxidation mechanism for kaempferitrin, which was supported by quantum chemical calculations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The aim of this study was to evaluate the effect of SPP with either fetal bovine serum (FBS) or deionized water (DW) on the bond strength (μTBS) of a Universal adhesive to dentin, in both etch-and-rinse (ER) and self-etch (SE) modes. The kinematic viscosity (cSt) of FBS and DW was measured at 25 °C ± 0.1 ºC. Seventy-two sound human molars were sectioned and randomly divided into three groups according to the SPP conditions: (1) Control (0 cm H 2 O), (2) SPP (15 cm H 2 O) with FBS, (3) SPP (15 cm H 2 O) with DW. Each group was subdivided (n = 10) based on the bonding modes: ER (37% phosphoric acid + ScothBond Universal Adhesive) or SE (ScothBond Universal Adhesive). Samples were then submitted to μTBS. Data were analyzed by Student's t test, two-way ANOVA and Tukey tests (p < 0.05). The cSt results showed that DW (23.59 ± 0.39) had significantly higher values than FBS (22.33 ± 0.06). With regard to SPP, the control group (36.1 MPa) had significantly higher values of μTBS when compared to the SPP using FBS (31.06 MPa) and SPP with DW (26.55 MPa). According to ANOVA, the bonding modes and the interaction of simulated pulpal pressure (SPP) did not statistically influence the results (p < 0.05). The presence of SPP reduced the bond strength of Universal adhesive to dentin. DW during SPP had significantly reduced bonding values when compared to FBS. Bonding strategies were not affected by SPP when evaluated in a short period of time (24 h)., (© 2021. The Society of The Nippon Dental University.)

Silver nanoparticles (AgNPs) are incredibly versatile nanostructures that more recently have been exploited to create advanced optoelectronic materials due enhancement of local magnetic field after its irradiation. However, the use of AgNPs as nanoantennas to amplify photophysical properties of close photosensitizer (PS) molecules in photodynamic therapy is still underexplored. The reason for that is the difficulty to control crucial parameters such as silver-PS distance in aqueous solution. In this scenario, here we propose a nanohybrid system where AgNP/PS distance is controlled by a thin layer of different Pluronic copolymers. The controllable distance and aqueous stability of proposed nanohybrids allow a tunable enhancement of fluorescence emission and singlet oxygen generation of some selected PS molecules. A detailed mechanism investigation demonstrated that the observed metal-enhanced photophysics is due to magnetic field enhancement close to AgNP surface (AgNP/PS distance-controlled effect) and the resonant coupling of AgNP hot electrons and HOMO-LUMO energies of the PS (AgNP/PS spectral overlap-controlled effect). These results show that the rational design in engineering new nanohybrid structures allowed photophysical improvement of PS molecules in aqueous solution in a tunable way and point out Pluronic-based AgNP/PS nanohybrids as a smart material for further developments aiming at theranostic applications in photodynamic therapy., (© 2021 American Society for Photobiology.)

Glycolic acid and lactic acid substituted zinc phthalocyanines were studied concerning their photophysical and photochemical properties in eight organic solvents (homogeneous medium) and in aqueous media with the presence of CTAB and PVP 360 surfactants. Solvent effects were investigated according to several physical solvent parameters, including studies that used more than one parameter at a time, such as the E T (30) scale and the Lippet-Mataga equation. Computational studies were realized and was found in good agreement with experimental data indicating J-type dimers' formation through hydrogen bonds, which may not affect the spectroscopic properties. Fluorescence lifetimes were recorded using a time-correlated single-photon counting setup (TCSPC) technique. The direct method (analyzing the phosphorescence decay curves of singlet oxygen at 1270 nm) was employed to study singlet oxygen quantum yields. Phthalocyanine macrocycle with lactic acid substituent showed better solvation arrangement than the glycolic derivative, which can be explained based on the presence of the methyl group bonded to the chain. The water solvation of Pc's in the presence of cationic surfactant (CTAB) and biocompatible polymer PVP 360 increses the importance of this study for appliance in photodynamic therapy (PDT)., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

In this study we report a novel theranostic lipid-polymer liposome, obtained from DPPC and the triblock copolymer F127 covalently modified with 5(6)-carboxyfluorescein (CF) for photodynamic applications. Due to the presence of F127, small unilamellar vesicle (SUV) liposomes were synthesized by a simple and fast thin-film hydration method without the need for an extrusion process. The vesicles have around 100 nm, low polydispersity and superb solution stability. The clinically used photosensitizer verteporfin (VP) was entrapped into the vesicles, mostly in monomeric form, with 90% loading efficiency. Stern-Volmer and fluorescence lifetime assays showed heterogeneous distribution of the VP and CF into the vesicles, ensuring the integrity of their individual photophysical properties. The theranostic properties were entirely photoactivatable and can be trigged by a unique wavelength (470 nm). The feasibility of the system was tested against the Glioblastoma multiforme cell line T98G. Cellular uptake by time-resolved fluorescence microscopy showed monomerized VP (monoexponential decay, 6.0 ns) at nucleus level, while CF was detected at the membrane by fluorescence microscopy. The strategy's success was supported by the reduction of 98% in the viability of T98G cells by the photoactivated lipid-polymer liposome with [VP] = 1.0 μmol L -1 . Therefore, the novel theranostic liposome is a potential system for use in cancer and ocular disease therapies., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Nanotechnology development provides new strategies to improve different treatment modalities by integration of multiple molecules in a single multifunctional nanoparticle. In this scenario, we highlight silver nanoparticles (AgNPs) favorable optical properties such as absorption and emission of light in the visible region of the spectrum. This allows its synergic combination with the photosensitizer molecule methylene blue (MB) in order to improve outcomes in photodynamic-based therapies. Therefore, we engineered here a new multifunctional nanostructured system based in the synthesis of pluronic-based AgNP/MB nanohybrids inspired by the concept of supramolecular chemistry. Silver reduction in water and Pluronic F127 aqueous solutions in the presence of hydrogen peroxide as etching agent at several concentrations induced the formation of anisotropic forms of AgNPs. Electronic absorption and TEM studies demonstrated a greater kinetic and morphological control for Pluronic synthetized NPs. The smart design of the proposed nanohybrids favored the enhancement of MB photophysical properties such as fluorescence emission and singlet oxygen production due a synergic action from resonant coupling between AgNP magnetic field and MB molecules. Results also demonstrated that AgNP-MB distance modulation in Pluronic matrix is a relevant parameter in MB photophysical improvement. Finally, since AgNP absorbance spectrum is dependent on AgNP shape, it plays a critical role in the improvement of MB photophysical properties. These results show that the rational design in engineering new multifunctional nanoparticles is essential and point out that Pluronic AgNP/MB nanohybrids as a smart material for further developments aiming photodynamic-based therapies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The objectives of this study were to determine the viability of removing Orange II (OII) dye by simulated solar photoelectro-Fenton (SSPEF) and to evaluate the stability of a WO 2.72 /Vulcan XC72 gas diffusion electrode (GDE) and thus determine its best operating parameters. The GDE cathode was combined with a BDD anode for decolorization and mineralization of 350 mL of 0.26 mM OII by anodic oxidation with electrogenerated H 2 O 2 (AO-H 2 O 2 ), electro-Fenton (EF) and photoelectro-Fenton (PEF) at 100, 150 and 200 mA cm -2 and SSPEF at 150 mA cm -2 . The GDE showed successful operation for electrogeneration, good reproducibility and low leaching of W. Decolorization and OII decay were directly proportional to the current density (j). AO-H 2 O 2 had a reduced performance that was only half of the SSPEF, PEF and EF treatments. The mineralization efficiency was in the following order: AO-H 2 O 2  < EF < PEF ≈ SSPEF. This showed that the GDE, BDD anode and light radiation combination was advantageous and indicated that the SSPEF process is promising with both a lower cost than using UV lamps and simulating solar photoelectro-Fenton process. The PEF process with the lowest j (100 mA cm -2 ) showed the best performance-mineralization current efficiency., (Copyright © 2019 Elsevier Ltd. All rights reserved.)