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To develop reactive oxygen species (ROS)-responsive anti-inflammatory materials and establish their structure–property correlations, a series of H2O2-eliminating materials (OxbCDs) were designed and synthesized by conjugating different phenylboronic acid pinacol ester (PBAP) groups onto a biocompatible scaffold compound β-cyclodextrin via varied linker groups. Both the H2O2-triggered hydrolysis profiles and H2O2-eliminating capacities of these materials were dependent on the chemical structure of the PBAP moieties. Together with the elucidation of hydrolysis mechanisms, we established structure–property correlations of these OxbCD materials. Extensive in vitro experiments revealed nanoparticles (NPs) based on OxbCDs showed no adverse biological effects on normal cells. OxbCD NPs could effectively inhibit inflammatory responses and oxidative stress in stimulated macrophages. Consistently, OxbCD NPs efficaciously alleviated the symptoms of peritonitis in mice, with respect to reducing the counts of neutrophils and macrophages as well as inhibiting the secretion of pro-inflammatory cytokines, chemokines, and oxidative mediators. Similarly, OxbCD NPs loaded with anti-inflammatory drugs displayed superior efficacy in an acute inflammation model of peritonitis in mice. More importantly, OxbCD NPs showed good biocompatibility after administration via different routes. Consequently, besides serving as anti-inflammatory materials, the newly developed H2O2-eliminating materials may be utilized as pharmacologically functional carriers for targeted therapy of many diseases associated with inflammation and oxidative stress.

A self-illuminating nanoparticle can function as an effective nanomedicine for inflammation imaging and cancer therapy.

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A novel reactive oxygen species (ROS)-responsive nanoplatform can be successfully manufactured from a ROS-triggerable β-cyclodextrin material. Extensive in vitro and in vivo studies validate that this nanoscaled system may serve as a new drug delivery vehicle with well-defined ROS-sensitivity and superior biocompatibility. This nanocarrier can be used for ROS-triggered transport of diverse therapeutics and imaging agents.

Classical molecular dynamic (MD) simulation of membrane proteins faces significant challenges in accurately reproducing and predicting experimental observables such as ion conductance and permeability due to its incapability of precisely describing the electronic interactions in heterogeneous systems. In this work, the free energy profiles of K(+) and Na(+) permeating through the gramicidin A channel are characterized by using the AMOEBA polarizable force field with a total sampling time of 1 μs. Our results indicated that by explicitly introducing the multipole terms and polarization into the electrostatic potentials, the permeation free energy barrier of K(+) through the gA channel is considerably reduced compared to the overestimated results obtained from the fixed-charge model. Moreover, the estimated maximum conductance, without any corrections, for both K(+) and Na(+) passing through the gA channel are much closer to the experimental results than any classical MD simulations, demonstrating the power of AMOEBA in investigating the membrane proteins.

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Gay–Berne anisotropic potential has been widely used to evaluate the nonbonded interactions between coarse-grained particles being described as elliptical rigid bodies. In this paper, we are presenting a coarse-grained model for twenty kinds of amino acids and proteins, based on the anisotropic Gay–Berne and point electric multipole (EMP) potentials. We demonstrate that the anisotropic coarse-grained model, namely GBEMP model, is able to reproduce many key features observed from experimental protein structures (Dunbrack Library), as well as from atomistic force field simulations (using AMOEBA, AMBER, and CHARMM force fields), while saving the computational cost by a factor of about 10–200 depending on specific cases and atomistic models. More importantly, unlike other coarse-grained approaches, our framework is based on the fundamental intermolecular forces with explicit treatment of electrostatic and repulsion-dispersion forces. As a result, the coarse-grained protein model presented an accurate description of nonbonded interactions (particularly electrostatic component) between hetero/homodimers (such as peptide–peptide, peptide–water). In addition, the encouraging performance of the model was reflected by the excellent correlation between GBEMP and AMOEBA models in the calculations of the dipole moment of peptides. In brief, the GBEMP model given here is general and transferable, suitable for simulating complex biomolecular systems.