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Flavonoids exhibit a broad range of biological activities. However, poor absorption of some flavonoids is a major limitation for use of flavonoids as nutraceuticals. To investigate the structure requirements for flavonoids intestinal absorption, transepithelial transport and cellular accumulation (CA) of 30 flavonoids were determined using the Caco-2 cell monolayer. The bilateral permeation of five types of flavonoids followed the order: flavanones ≥ isoflavones > flavones ≥ chalcones > flavonols. The concentration of flavonoids accumulated in cells did not correlate with cell penetration since the correlation coefficient between the apparent permeability coefficient (Papp) and their corresponding CA was poor (R2 < 0.3). Most flavonoids exhibited a ratio of 0.8–1.5 for Papp A to B/Papp B to A, suggesting passive diffusion pathways. However, luteolin, morin and taxifolin may involve the efflux mechanisms. The quantitative structure-permeability relationship (QSPR) study demonstrated that the intestinal absorption of flavonoids can be related to atomic charges on carbon 3′ (QC3′), molecule surface area (SlogP_V3), balance between the center of mass and position of hydrophobic region (vsurf_ID1) and solvation energy of flavonoids (E_sol). These results provide useful information for initially screening of flavonoids with high intestinal absorption.

Carbon quantum dots derived from gentamicin sulfate show low drug resistance, eradication of mature Staphylococcus aureus biofilm and low toxicity to mammalian cells.

Stimuli-responsive drug delivery and release have a great significance in cancer therapy.

The size and morphology of metals determine their plasmon resonances. How to elegantly tune their architectures to obtain optical properties as required (e.g., strong absorption in the near-infrared (NIR) wavelengths) is a bottleneck for phototherapy. Inspired by biomineralization, we develop a simple but robust strategy to fabricate silver nanocages (Ag NCs) based on peptide-directed mineralization of silver. The Ag NCs are organic–inorganic hybrids with octreotide (OCT) templated decoration of Ag shells that are composed of Ag NPs. This hierarchical organization makes Ag NPs get together in close proximity, which facilitates ultrastrong plasmonic coupling to shift the resonant excitation from the visible (420 nm) to the NIR region (810 nm). In addition, the surface plasmon resonance peak of the Ag NCs in the NIR region can be subtly tuned by varying the volume of added silver nitrate (AgNO3) to control the size and morphology of mineralized Ag NCs. The Ag NCs have a light-to-heat conversion efficiency of 46.1%, which is to our knowledge the highest among Ag-based photothermal agents (PTAs). The Ag NCs can selectively induce death of cancer cells in vitro under NIR irradiation at 808 nm and show improved cytocompatibility for normal cells relative to pure Ag NPs. Following intratumor injection into uterine cervix cancer cells (U14) tumor-bearing mice, Ag NCs exert remarkable antitumor performance with tumor killing efficacy up to 82.7% and good biocompatibility in photothermal therapy, suggesting their potential application to work as photothermal nanomedicine for cancer therapy.

The barrier-improving functions of fermented blueberry pomace (FBP) and its potential mechanism were investigated in this study.

Research on the incorporation of cutting-edge nano-antibacterial agent for designing dental materials with potent and long-lasting antibacterial property is demanding and provoking work. In this study, a novel resin-based dental material containing photocurable core-shell AgBr/cationic polymer nanocomposite (AgBr/BHPVP) was designed and developed. The shell of polymerizable cationic polymer not only provided non-releasing antibacterial capability for dental resins, but also had the potential to polymerize with other methacrylate monomers and prevented nanoparticles from aggregating in the resin matrix. As a result, incorporation of AgBr/BHPVP nanocomposites did not adversely affect the flexural strength and modulus but greatly increased the Vicker's hardness of resin disks. By continuing to release Ag ions without the impact of anaerobic environment, resins containing AgBr/BHPVP nanoparticles are particularly suitable to combat anaerobic cariogenic bacteria. By reason of the combined bactericidal effect of the contact-killing cationic polymers and the releasing-killing Ag ions, AgBr/BHPVP-containing resin disks had potent bactericidal activity against S. mutans. The long-lasting antibacterial activity was also achieved through the sustained release of Ag ions due to the core-shell structure of the nanocomposites. The results of macrophage cytotoxicity showed that the cell viability of dental resins loading less than 1.0 wt% AgBr/BHPVP was close to that of neat resins. The AgBr/BHPVP-containing dental resin with dual bactericidal capability and long term antimicrobial effect is a promising material aimed at preventing second caries and prolonging the longevity of resin composite restorations.