Petersaaen8470

Liquid metals (LMs), typically gallium and its alloys, are emerging functional materials for nanotechnology, yet the applications of LM nanoparticles (LMNPs) in biomedical areas are still in their infancy. This predicament occurs primarily because LMNPs are generally synthesized with inadequately protected surfaces rendering rapid uncontrollable oxidation in physiological conditions. Herein, we show that depositing a polymeric supra-nanoparticle shell on LMNPs through sonochemical assembly can alleviate their oxidation kinetics and maintain their designed functionalities, even during hyperthermia processing. The LMNPs with polymer encapsulation promise to be excellent candidate materials for stable, biocompatible, and reusable photothermal converters under near-infrared (NIR) laser irradiation, showing doubled photothermal conversion efficiency compared with unprotected ones. Besides, they are employed, alone or synergistically with a hydrogel matrix, as potent photothermal bactericidal agents, both in vitro and in vivo. Specifically, the LMNPs-embedded agarose hydrogel allows the disinfection and concurrently accelerated healing of full-thickness skin wounds. The nanoshell-enabled heat resistance of LMNPs is expected to broaden the horizons of LM-based nano/biomedicine, potentially against superbugs and cancer.High foulant adhesion remains a critical issue in a wide range of industries, such as ice accretion on aircraft, biofoulants on ships, wax build-up within pipelines, and scale formation in water remediation. Previous anti-fouling surfaces have only shown promise for reducing the adhesion of a single foulant system; a multi-foulant anti-fouling technology remains elusive. Here, we introduce a mechanical metamaterial-based approach to develop anti-fouling surfaces applicable to a wide range of fouling substances. The suspended kirigami inverted nil-adhesion surfaces, or SKINS, show significantly reduced adhesion of ice, different waxes, dried mud, pressure-sensitive adhesive tape, and a marine hard foulant simulant. SKINS mimic the wrinkling of hard films adhered to soft substrates. Foulant adhesion can be minimized by this wrinkling, which may be controlled by tuning the kirigami motif, sheet material, and foulant dimensions. SKINS reduce adhesion mechanically and were found to be independent of surface energy, enabling their fabrication from commonplace hydrophilic polymers like cellulose acetate. Optimized SKINS exhibited extremely low foulant adhesion, for example, ice adhesion strengths less than 5 kPa (a >250-fold reduction from aluminum substates), and were found to maintain their performance on curved surfaces like transmission cables. The low foulant adhesion persisted over 30 repeated foulant deposition and removal cycles, demonstrating the anti-fouling durability of SKINS. Overall, SKINS offers a previously unexplored route to achieving low foulant adhesion that is highly tunable in both geometry and material selection, is applicable to many different fouling substances, and maintains extremely low foulant adhesion even on complex substrates over large fouled interfaces.Ice readily sheds from weak oil-swollen polymer gels but tends to adhere to mechanically robust coatings. This paper reports bilayer coatings that simultaneously possess high bulk hardness but low ice adhesion. These coatings are prepared by cocuring a triisocyanate, P#'-g-PDMS [a methacrylate polyol bearing poly(dimethylsiloxane) (PDMS) side chains with # being 1, 2, or 3 and g denoting graft], and optionally a methacrylate polyol P#. The self-assembly of the system during coating formation yields a PDMS brush layer on the surface of the cross-linked polyurethane matrix. After the surface PDMS layer is lubricated with a silicone oil, this coating exhibits an ice adhesion τ that is 10 000-fold lower than that of a triisocyanate/P# coating. LL37 nmr Ice slides under its own weight on such a coating at a tilt angle of 3°. Yet, the coating matrix is harder than poly(ethylene terephthalate), a widely used plastic. Additionally, such a coating maintains its low τ values for more than 10 consecutive icing/deicing cycles. Subsequent increases in τ are reversed by allowing time for the replenishment of the depleted surface lubricant with that released from the coating matrix. This design opens the door for effective yet hard ice-shedding polymer coatings.Renewable pressure-sensitive adhesive (PSA) is an emerging field in adhesive industries as it is an excellent green alternative to depleting petroleum-sourced adhesives. Herein, we report the development of novel bio-sourced UV-curable PSAs with ∼50% biomass content originating from alkali lignin, cardanol, and linseed oil. Bio-based prepolymers cardanoldiol acrylate (CDA) and acrylated epoxidized linseed oil (AELO) were synthesized and used to prepare polyurethane acrylate (PUA)-based PSA systems. Alkali-lignin-based acrylates (LAs) in the liquid phase were incorporated into the PUA/AELO PSA system at 10-30 wt % loading to tune the functional properties. The Fourier transform infrared spectroscopy (FTIR) analysis showed weakened cross-linking in the PSA systems on LA addition, which is desirable for removable PSA applications. The single glass-transition temperature (Tg) noticed in all of the PSA formulations revealed good miscibility among the oligomers/prepolymers. The viscoelastic window also confirmed that the incorporation of 10-20% LA could improve the viscoelastic properties effectively to be used as removable PSAs. The addition of 20% LA into the PUA-based PSA system showed reasonable tackiness, lap shear adhesion (166 kPa), and 180° peel strength (∼2.1 N/25 mm) for possible nonstructural or semistructural applications. Lignin improved the thermal stability by hindering the degradation rate even at higher temperatures. Therefore, lignin-based PSAs with a high bio-based content paved the way of replacing petro-sourced PSA by proper tuning of the lignin content and modifications.To drive the development of perovskite solar cells (PSCs), hole-transporting materials are imperative. In this context, pyridine derivatives are being probed as small molecules-based hole-transporting materials due to their Lewis base and electron-deficient unit. Herein, we focused our investigation on pyridine isomer molecules 4,4'-(10-(pyridin-x-yl)-10H-phenothiazine-3,7-diyl)bis(N,N-bis(4-methoxyphenyl)aniline) (x = 2, 3, or 4), in which the pyridine nitrogen heteroatom is located at the 2, 3, and 4 positions, named as 2PyPTPDAn, 3PyPTPDAn, and 4PyPTPDAn, respectively. We decipher the structure-properties-device performance relationship impacted by the different N-atom positions in pyridine. In the case of 3PyPTPDAn, the partial orbital overlap between highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) favors the generation of neutral excitons and hole transport, as well as improves the film-formation ability, and this induces efficient hole extraction as compared to their 2,4 analogues. The solar cells fabricated with 3PyPTPDAn gave on-par photovoltaic performance as that of typical Spiro-OMeTAD, and higher performance than those of 2PyPTPDAn and 4PyPTPDAn. The hydrophobicity and homogeneous film properties of 3PyPTPDAn add merits to the stability. This work emphasizes the guidelines to develop small molecules for organic solar cells, organic light-emitting diodes, and thermally activated delayed fluorescence.The structure and composition of copper surfaces in aqueous solutions of benzotriazole (BTAH) and NaCl was investigated by sum frequency vibrational spectroscopy as a function of concentration and bias during cyclic voltammetry experiments. We found that the protection provided by the BTAH films formed at the copper surface is effective for negative bias voltages below the open circuit potential (OCP) but not at positive voltages where Cl- displaces BTAH. By measuring the Gibbs adsorption energy of BTAH and Cl-, we found that a particularly stable Cl- structure is formed around the OCP, suggesting that electronegative additives that move the OCP to higher negative values can improve BTAH protection, which we confirmed by the addition of a negatively charged sodium dodecyl sulfate surfactant.Rapid and sensitive diagnostics in the early stage of bacterial infection and immediate treatment play critical roles in the control of infectious diseases. However, it remains challenging to develop integrated systems with both rapid detection of bacterial infection and timely on-demand disinfection ability. Herein, we demonstrate a photonic hydrogel platform integrating visual diagnosis and on-site photothermal disinfection by incorporating Fe3O4@C nanoparticles into a poly(hydroxyethyl methacrylate)-co-polyacrylamide (PHEMA-co-PAAm) matrix. In vitro experiments demonstrate that such a hydrogel can respond to pH variation caused by bacterial metabolism and generate the corresponding color changes to realize naked-eye observation. Meanwhile, its excellent photothermal conversion ability enables it to effectively kill bacteria by destroying cell membranes under near-infrared irradiation. Moreover, the pigskin infection wound model also verifies the bacterial detection performance and disinfection ability of the hydrogel in vivo. Our strategy demonstrates a new approach for visual diagnosis and treatment of bacterial infections.Human LL-3717-29 is an antimicrobial peptide forming thermostable supramolecular fibrils that surround bacterial cells. The crystal structure of LL-3717-29 bearing an I24C substitution of most buried position in the fibril revealed disulfide-bonded dimers that further assembled into a fibrillar structure of densely packed helices. We further demonstrated the position-dependent controllable antibacterial activity of LL-3717-29 I24C and other cysteine mutants, mediated by regulation of intermolecular disulfide bonds and their role in the formation of supramolecular structures. The morphology of the fibrils and their antibacterial mechanism of action might be dependent on their interactions with specific bacteria. The significant effect of disulfide bonds on the assembly into supramolecular structures and their sensitivity to reducing/oxidizing conditions may explain why short helical antimicrobial peptides with a single cysteine and an odd number of cysteines are selected against in nature.The use of nanoparticles as carriers to deliver pharmacologically active compounds to specific parts of the body via the bloodstream is a promising therapeutic approach for the effective treatment of various diseases. To reach their target sites, nanocarriers (NCs) need to circulate in the bloodstream for prolonged periods without aggregation, degradation, or cargo loss. However, it is very difficult to identify and monitor small-sized NCs and their cargo in the dense and highly complex blood environment. Here, we present a new fluorescence correlation spectroscopy-based method that allows the precise characterization of fluorescently labeled NCs in samples of less than 50 μL of whole blood. The NC size, concentration, and loading efficiency can be measured to evaluate circulation times, stability, or premature drug release. We apply the new method to follow the fate of pH-degradable fluorescent cargo-loaded nanogels in the blood of live mice for periods of up to 72 h.