Surface biofunctionalization with structurally perturbed albumin, as well as with other plasmatic proteins, inhibits the initial bacterial adhesion and biofilm formation, involved in numerous healthcare-associated infections. In fact, we have reported this protective effect with thermally treated plasmatic proteins, such as albumin and fibrinogen, adsorbed on flat silica surfaces. Here, we show that albumin biofunctionalization also works properly on flat Ti6Al4V substrates, which are widely used to fabricate medical devices. The protective effect is conserved even in biologically relevant fluids, containing other proteins that potentially adsorb onto and/or displace preadsorbed albumin from the biofunctionalized substrates. We further demonstrate that the presence of structurally perturbed albumin on the substrate does not trigger macrophage activation and the release of inflammatory mediators. Consequently, surface biofunctionalization with thermally perturbed albumin is a simple strategy to prepare antibacterial, nonimmunogenic medical devices.

The rapid development of wearable technology, flexible electronics, and human-machine interaction has brought about revolutionary changes to the fields of motion analysis and physiological monitoring. Sensors for detecting human motion and physiological signals have become a hot topic of current research. Inspired by the muscle fiber structure, this paper proposed a highly stable strain sensor that was composed of stretchable Spandex fibers (SPF), multiwalled carbon nanotubes (MWCNTs), and silicone rubber (Ecoflex). This sensor adopted an immersion coating process in which MWCNTs were conformally deposited on SPF, and Ecoflex was filled into the fiber interstices, completing the encapsulation and filling of the SPF to construct a stable three-dimensional conductive network. Thanks to the filling of Ecoflex, contact between conductive fibers during the stretching process was avoided, resulting in a significant change in the resistance. The sensitivity of the sensor reached 54.84, which is 10 times higher than before the Ecoflex filling with a stretchable strain range of up to 70%. The encapsulation of Ecoflex also prevented the detachment of MWCNTs on the fibers during stretching, improving the mechanical stability. The sensor can be easily attached to the surface of human skin to rapidly monitor various human motion signals. Furthermore, the sensor was related to the manipulator through wireless Bluetooth to realize the intelligent control of the manipulator. This work not only provided a more precise data monitoring method for medical and motion analysis fields but also offered an innovative solution for manipulator control.

Self-assembly of amino acids and short-peptide derivatives attracted significant curiosity worldwide due to their unique self-assembly process and wide variety of applications. Amino acid is considered one of the important synthons in supramolecular chemistry. Self-assembly processes and applications of unfunctionalized native amino acids have been less reported in the literature. In this article, we are first-time reporting the self-assembly process of tyrosine (Tyr), an aromatic amino acid, in dimethyl sulfoxide (DMSO) solvent. Most of the studies related to Tyr self-assembly were reported in different aqueous solutions. In our work, we studied the self-assembly in several common organic solvents and found that Tyr could self-assemble into a supramolecular gel in dimethyl sulfoxide (DMSO) solvent. The self-assembly process was investigated by several techniques, such as UV-vis, fluorescence, FTIR, and NMR spectroscopy. Morphological features on the nanoscale were investigated through scanning electron microscopy (SEM). SEM images indicated the formation of nanofibrils with high aspect ratios. The supramolecular gel property was investigated by different rheological experiments. Computational study on the self-assembly process of Tyr in DMSO medium suggested that noncovalent interactions like hydrogen bonding and π-π stacking among the Tyr molecules played a prominent role. Finally, the charge-transfer complex formation ability of electron-rich Tyr with electron-deficient 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) was studied. In the presence of DDQ due to the charge-transfer complex formation, the supramolecular gel converted into a reddish color solution, and their fibrillar nanoscale morphologies collapsed.

Nontraditional luminogens (NTLs) without large π-conjugated aromatic structures have attracted a great deal of attention in recent years. Developing NTLs with red-shifted and enhanced emissions remains a great challenge. In this work, we developed a NTL composed of three components, i.e., polymaleic acid (PMA), arginine (Arg), and polyacrylamide (PAM), and investigated its photoluminescent behavior and mechanism. Compared with the single components and binary components, the PMA/Arg/PAM solid exhibited two red-shifted emission peaks at 510 and 562 nm and higher quantum yields. Structural characterizations demonstrated that hydrogen bonds formed between the nonconventional chromophores in PMA and Arg lead to more extended through-space conjugation and rigidified conformations, which is the fundamental reason for the red-shifted emission and higher quantum yield of the PMA/Arg/PAM solid. In addition, theoretical calculations proved that excited-state proton transfer occurs between the carboxyl groups of PMA and amino groups of Arg via photoexcitation, resulting in dual emissions in the PMA/Arg/PAM solid. This work provides a deeper understanding of the photoluminescence mechanism of NTLs based on multiple hydrogen bonds and is helpful in guiding the design of NTLs with red-shifted and enhanced emissions.

Coacervation is generally treated as a liquid-liquid phase separation process and is controlled mainly by thermodynamics. However, kinetics could make a dominant contribution, especially in systems containing multiple interactions. In this work, using peptides of (XXLY)6SSSGSS to tune the charge density and the degree of hydrophobicity, as well as to introduce secondary structures, we evaluated the effect of kinetics on biphasic coacervates formed by peptides with single-stranded oligonucleotides and quaternized dextran at varying pH values. Only in the case where the charge density is constant and the electrostatic interaction is the major driving force for Coacervation is the effect of kinetics negligible. When pH-dependent electrostatic interaction and hydrophobic interaction are involved or the peptides form secondary structures, the Coacervation process is then path-dependent, indicating that the kinetics controls the phase separation process. The Coacervation by combining two different peptides suggests that the peptide with a higher charge density plays a leading role in the early stage, while the cooperation of both peptides takes over afterward. Our work demonstrates that it is normal to observe coacervates with different morphologies and functions due to kinetic control, especially in living cells. Peptides with minimized sequences are a practical approach to reveal the mechanism of Coacervation processes controlled by kinetics.

The term "aerophilic surface" is used to describe superhydrophobic surfaces in the Cassie-Baxter wetting state that can trap air underwater. To create aerophilic surfaces, it is essential to achieve a synergy between a low surface energy coating and substrate surface roughness. While a variety of techniques have been established to create surface roughness, the development of rapid, scalable, low-cost, waste-free, efficient, and substrate-geometry-independent processes for depositing low surface energy coatings remains a challenge. This study demonstrates that fluorinated phosphate ester, with a surface tension as low as 15.31 mN m-1, can form a self-assembled monolayer on metal oxide substrates within seconds using a facile wet-chemical approach. X-ray photoelectron spectroscopy was used to analyze the formed self-assembled monolayers. Using nanotubular morphology as a rough substrate, we demonstrate the rapid formation of a superhydrophobic surface with a trapped air layer underwater.

Plasma membrane (PM) simulations at longer length and time scales at nearly atomistic resolution can provide invaluable insights into cell signaling, apoptosis, lipid trafficking, and lipid raft formation. We propose a coarse-grained (CG) model of a mammalian PM considering major lipid head groups distributed asymmetrically across the membrane bilayer and validate the model against bilayer structural properties from atomistic simulation. Using the proposed CG model, we identify a recurring pattern in the passive collective cholesterol transbilayer motion and study the individual cholesterol flip-flop events and associated pathways along with lateral ordering in the bilayer during a flip-flop event. We identify two discrete cholesterol flip-flop pathways: (i) a systematic rototranslational pathway and (ii) intraleaflet inversion followed by interleaflet translation (or reverse). We observe a periodic cholesterol enrichment in the exoplasmic leaflet of the PM bilayer and examine the underlying cholesterol-lipid affinities. We observe closer association between cholesterol and palmitoylsphingomyelin (PSM) lipid, relative to other lipids, and conclude that the cholesterol enrichment in the exoplasmic leaflet can be attributed to higher PSM content in that leaflet, together leading to formation of short-lived PSM-cholesterol-rich domains.

This study investigates the surfactant properties and efficiency of linear and Guerbet-type amino acid surfactants. Utilizing a Wilhelmy plate method, we assessed the colloidal efficiency of these surfactants, with the lowest observed critical micelle concentration at 0.046 mmol L-1, significantly reducing surface tension to as low as 25.1 mN·m-1. Furthermore, the self-diffusion coefficients of the various surfactants have been determined through 1H pulsed-field gradient nuclear magnetic resonance diffusion-ordered spectroscopy. The self-diffusion coefficients are linked to the surface tension reduction as a function of concentration to determine the characteristic time scale of diffusion. In this work, the characteristic time scale of diffusion of a series of surfactants was calculated to investigate the interfacial coverage efficiency. Our findings indicate an inverse relationship between the characteristic time scale of diffusion and critical micelle concentrations across surfactants with hydrocarbon tail lengths of 8-22 carbons. Shorter tails correspond to lower colloidal efficiencies, but rapid surface tension reduction, resulting in the characteristic time scale of diffusion values ranging from 120 ns to 2.15 s. This property is crucial for applications requiring rapid action, such as enhancing aerosol efficiency, improving dispersion, and wetting materials in products.

Constructing wide and narrow band gap heterogeneous semiconductors is a method to improve the activity of photocatalysts. In this paper, CMS/ZnO heterojunctions were prepared by solvothermal loading of ZnO particles on the surface of Cu2MoS4 nanosheets. The photocatalytic H2 precipitation rate is about 545 μmol·g-1·h-1, which is 6.8 times that of Cu2MoS4 and 3 times that of ZnO without any cocatalyst. After etching modification of CMS, the photocatalytic hydrogen production efficiency of the ECMS/ZnO heterojunction is further improved. Its hydrogen production efficiency reaches about 1115 μmol·g-1·h-1, which is 9 times that of ECMS and 6 times that of ZnO. The reasons are mainly attributed to the following two factors: (1) the formation of the ECMS/ZnO type-II-type heterojunction facilitates the effective separation of photogenerated electrons and holes; (2) the band structure of Cu2MoS4 was optimized by etching modification, which made the ECMS/ZnO heterojunction have lower interfacial charge transfer resistance and improved the photocatalytic hydrogen production activity of the heterojunction.

The mechanisms of NO reduction by CO over nitrogen-doped graphene (N-graphene)-supported single-atom Ni catalysts in the presence of O2, H2O, CO2, and SO2 have been studied via density functional theory (DFT) modeling. The catalyst is represented by a single Ni atom bonded to four N atoms on N-graphene. Several alternative reaction pathways, including adsorption of NO on the Ni site, direct reduction of NO by CO, decomposition of NO to N2O followed by reduction of N2O to N2, formation of active oxygen radical O*, and reduction of O* by CO, were hypothesized and the energy barrier corresponding to each of the reaction steps was calculated using DFT. The most probable pathway was found to be that NO adsorbed on the Ni site decomposes via the Langmuir-Hinshelwood mechanism to form N2O and subsequently N2, leaving an active oxygen radical (O*) on the surface, which is then reduced by CO. The large adsorption energy of NO on the Ni site results in strong resistance to CO2, SO2, O2, and water vapor. The activation energy of N2O reduction to N2 was found to be larger than those of NO decomposition to N2O and active oxygen radical reduction by CO, illustrating that the step of N2O reduced to N2 is the rate-controlling step.