Interfacial Complex Research Articles

An electrochemical molecular assay for the detection of cancer-associated Thomsen-Friedenreich glycans.

e15046 Background: Abnormal glycosylation is a fundamental characteristic in cancer cells, where expression of glycans such as Thomsen-Friedenreich (T), Tn, and sialyl-Tn (STn) are related to particular tumour patterns. T, Tn and STn antigens are unusually short and truncated O-glycans expressed on glycoproteins synthesized within cancer cells and not normally found in healthy tissue or circulating within the blood. The association between blood circulating T-glycans and cancer progression and poor prognosis is now well-known and highlights great potential as biomarkers for cancer screening, diagnosis, and surveillance of diseases during treatment and following remission. Despite this potential, there is currently no established molecular assay for detecting or quantifying these biomarkers in blood biopsy samples. Methods: Using a test strip format reminiscent of a blood glucose test, a new electrochemical molecular assay is introduced for the detection of short O-glycans directly in unprocessed bodily fluids. This assay is based on a self-assembling sensing interface consisting of two glycoproteins, recombinant human lubricin (LUB) and peanut agglutin (PNA). In this interface, the LUB functions as both an anti-fouling layer which mitigates electrode passivation in blood and as a crucial component in the biosensing mechanism for generating readable electrical signals in the presence of target glycans. The PNA, a plant-based lectin, presents high binding specificity towards the T glycoform and functions as the sensor recognition element which is bound to the LUB through T glycans naturally present in the highly glycosylated protein backbone. In this sensing interface, electrical signals are generated by engineering a redox reporter, methylene blue into the LUB/PNA interfacial complex, where the electrical signal is altered by the capture of target glycans by PNA and its impact on the molecular dynamics of the LUB/PNA interfacial complex. Results: Using this test strip, it is possible to detect short cancer-related glycans in concentrations as low as nanomolar directly in small volumes of unprocessed whole blood. These test strips likewise show comparable results to an ELISA test developed in parallel for the detection of short O-glycans. The tests carried out with retrospective blood plasma samples from patients presenting three different tumour types, including prostate (18 patients), colorectal (15 patients), and breast cancer (6 patients), and plasma samples from healthy donors (10 different donors) showed differentiation of response signals between healthy and diseased patients. Conclusions: These findings highlight the clinical potential of this new disposable test strip for the detection of tumour associated glycans, which can be incorporated into point-of-care devices, for cancer monitoring and perhaps one day in screening and diagnosis.

Charge-Transfer Complex-Based Artificial Layers for Stable and Efficient Zn Metal Anodes

Herein, we report a charge-transfer complex electrolyte additive, 7,7,8,8-tetracyanoquinodimethane (TCNQ), with high Zn affinity, which was tightly adsorbed on the surface of a Zn anode to form a dense and robust interfacial complex layer and suppress the activity of H2O. As verified by comprehensive experimental and computational analyses, this complex layer could construct a Zn–Zn(TCNQ)2 Ohmic contact interface, guide rapid ion/electron transport, ameliorate electric field distribution, and inhibit the direct contact between the active H2O and Zn anode, demonstrating a dendrite-free Zn anode and facile Zn plating/stripping kinetics. Consequently, the Zn||Zn symmetrical cell exhibits a high Zn plating/stripping reversibility of over 1000 h at 20 mA cm–2 and 5 mA h cm–2 and a high depth of discharge (43%). Moreover, the Zn||MnO2 full cell delivers a high capacity of 143.3 mA h g–1 at 2000 mA g–1 even after 4000 cycles and a capacity retention of 94.7% after returning to 100 mA g–1.

Clathrin-mediated endocytosis facilitates the internalization of Magnaporthe oryzae effectors into rice cells.

Fungi and oomycetes deliver effectors into living plant cells to suppress defenses and control plant processes needed for infection. Little is known about the mechanism by which these pathogens translocate effector proteins across the plasma membrane into the plant cytoplasm. The blast fungus Magnaporthe oryzae secretes cytoplasmic effectors into a specialized biotrophic interfacial complex (BIC) before translocation. Here, we show that cytoplasmic effectors within BICs are packaged into punctate membranous effector compartments that are occasionally observed in the host cytoplasm. Live cell imaging with fluorescently labeled proteins in rice (Oryza sativa) showed that these effector puncta colocalize with the plant plasma membrane and with CLATHRIN LIGHT CHAIN 1, a component of clathrin-mediated endocytosis (CME). Inhibiting CME using virus-induced gene silencing and chemical treatments resulted in cytoplasmic effectors in swollen BICs lacking effector puncta. By contrast, fluorescent marker colocalization, gene silencing, and chemical inhibitor studies failed to support a major role for clathrin-independent endocytosis in effector translocation. Effector localization patterns indicated that cytoplasmic effector translocation occurs underneath appressoria before invasive hyphal growth. Taken together, this study provides evidence that cytoplasmic effector translocation is mediated by CME in BICs and suggests a role for M. oryzae effectors in coopting plant endocytosis.

The nuclear effector MoHTR3 of Magnaporthe oryzae modulates host defence signalling in the biotrophic stage of rice infection.

Fungal effectors play a pivotal role in suppressing the host defence system, and their evolution is highly dynamic. By comparative sequence analysis of plant-pathogenic fungi and Magnaporthe oryzae, we identified the small secreted C2 H2 zinc finger protein MoHTR3. MoHTR3 exhibited high conservation in M. oryzae strains but low conservation among other plant-pathogenic fungi, suggesting an emerging evolutionary selection process. MoHTR3 is exclusively expressed in the biotrophic stage of fungal invasion, and the encoded protein localizes to the biotrophic interfacial complex (BIC) and the host cell nucleus. The signal peptide crucial for MoHTR3' secretion to the BIC and the protein section required for its translocation to the nucleus were both identified by a functional protein domain study. The host-nuclear localization of MoHTR3 suggests a function as a transcriptional modulator of host defence gene induction. After ΔMohtr3 infection, the expression of jasmonic acid- and ethylene-associated genes was diminished in rice, in contrast to when the MoHTR3-overexpressing strain (MoHTR3ox) was applied. The transcript levels of salicylic acid- and defence-related genes were also affected after ΔMohtr3 and MoHTR3ox application. In pathogenicity assays, ΔMohtr3 was indistinguishable from the wild type. However, MoHTR3ox-infected plants showed diminished lesion formation and hydrogen peroxide accumulation, accompanied by a decrease in susceptibility, suggesting that the MoHTR3-induced manipulation of host cells affects host-pathogen interaction. MoHTR3 emphasizes the role of the host nucleus as a critical target for the pathogen-driven manipulation of host defence mechanisms and underscores the ongoing evolution of rice blast's arms race.

The transcriptional landscape of plant infection by the rice blast fungus Magnaporthe oryzae reveals distinct families of temporally co-regulated and structurally conserved effectors.

The rice blast fungus Magnaporthe oryzae causes a devastating disease that threatens global rice (Oryza sativa) production. Despite intense study, the biology of plant tissue invasion during blast disease remains poorly understood. Here we report a high-resolution transcriptional profiling study of the entire plant-associated development of the blast fungus. Our analysis revealed major temporal changes in fungal gene expression during plant infection. Pathogen gene expression could be classified into 10 modules of temporally co-expressed genes, providing evidence for the induction of pronounced shifts in primary and secondary metabolism, cell signaling, and transcriptional regulation. A set of 863 genes encoding secreted proteins are differentially expressed at specific stages of infection, and 546 genes named MEP (Magnaportheeffector protein) genes were predicted to encode effectors. Computational prediction of structurally related MEPs, including the MAX effector family, revealed their temporal co-regulation in the same co-expression modules. We characterized 32 MEP genes and demonstrate that Mep effectors are predominantly targeted to the cytoplasm of rice cells via the biotrophic interfacial complex and use a common unconventional secretory pathway. Taken together, our study reveals major changes in gene expression associated with blast disease and identifies a diverse repertoire of effectors critical for successful infection.

New insights into cupric ion-mediated ligand-to-metal charge transfer between TiO2 with peroxydisulfate under visible light for bolstering benzophenone-3 degradation

Effective removal of hazardous and low biodegradable benzophenone-3 (BP-3) has been a challenging problem. In this study, a new Vis/TiO2/PDS/Cu2+ system was constructed to evaluate the catalytic performance of BP-3 during the co-induced ligand-to-metal charge transfer (LMCT) process by Cu2+, PDS and TiO2. Under visible light irradiation, trace Cu2+ efficiently triggering LMCT process from PDS to TiO2 via Cu–O bridging effect was firstly reported. In this LMCT-mediated photocatalysis process, Cu2+ was not only involved in the formation of visible-light responsive TiO2-Cu-PDS complexes but also inhibited the back electron transfer and promoted PDS activation by accelerating the electron transfer from the conductive band (CB) of TiO2 to PDS via Cu2+/Cu+ cycle. Compared with BP–3 removal in Cu2+/PDS system (18%) and Vis/TiO2 system (48%), that in Vis/TiO2/Cu2+ system (58%) and Vis/TiO2/PDS system (54%) exhibited a slight improvement. It was worth noting that BP-3 removal in Vis/Cu2+/TiO2/PDS system reached 91% within 30 min and the corresponding TOC removal was up to 76% in 120 min, which proved that the significantly enhancement of BP-3 degradation in Vis/Cu2+/TiO2/PDS system. Meanwhile, this system could maintain efficient catalytic performance in a wide pH range from 3 to 8. The formation of an interfacial charge transfer complex of Cu-PDS on TiO2, and the boosted generation of O2–, SO4− and HO radicals over the Vis/Cu2+/TiO2/PDS system were confirmed. Notably, visible light excited Cu-PDS complexes to distribute electrons to TiO2 (CB) via Cu–O bridge action, thereby inducing the enhanced visible-light activity of TiO2 and achieving superior catalytic performance for various pollutants in Vis/Cu2+/TiO2/PDS system. Furthermore, enhanced activation mechanisms of TiO2 and PDS by visible-light induced LMCT process were proposed in detail. Hydroxylation, demethylation and ring-opening dominated BP-3 degradation, and the weakened toxicity of BP-3 in Vis/TiO2/PDS/Cu2+ system was confirmed via the distinct increase of E.coli colonies numbers at the introduction of intermediates. This study offers new insights into LMCT activation approach and broadens the understanding of the ability of Cu2+ to be applied in photo-activated persulfate-based advanced oxidation processes for environmental remediation.

Digestion behaviour of capsaicinoid-loaded emulsion gels and bioaccessibility of capsaicinoids: Effect of emulsifier type

In this study, the effect of emulsifier type, i.e. whey protein versus Tween 80, on the digestion behaviour of emulsion gels containing capsaicinoids (CAPs) was examined. The results indicate that the CAP-loaded Tween 80 emulsion gel was emptied out significantly faster during gastric digestion than the CAP-loaded whey protein emulsion gel. The Tween-80-coated oil droplets appeared to be in a flocculated state in the emulsion gel, had no interactions with the protein matrix and were easily released from the protein matrix during gastric digestion. The whey-protein-coated oil droplets showed strong interactions with the protein matrix, and the presence of thick protein layer around the oil droplets protected their liberation during gastric digestion. During intestinal digestion, the CAP-loaded Tween 80 emulsion gel had a lower extent of lipolysis than the CAP-loaded whey protein emulsion gel, probably because the interfacial layer formed by Tween 80 was resistance to displacement by bile salts, and/or because Tween 80 formed interfacial complexes with bile salts/lipolytic enzymes. Because of the softer structure of the CAP-loaded Tween 80 emulsion gel, the gel particles were broken down much faster and the oil droplets were liberated from the protein matrix more readily than for the CAP-loaded whey protein emulsion gel during intestinal digestion; this promoted the release of CAP molecules from the gel. In addition, the Tween 80 molecules displaced from the interface would participate in the formation of mixed micelles and would help to solubilize the released CAP molecules, leading to improved bioaccessibility of CAP. Information obtained from this study could be useful in designing functional foods for the delivery of lipophilic bioactive compounds.

Impact of polyelectrolyte complex layer on the stability of palm oil multiple emulsions encapsulating a water-soluble compound during heating, cooling, and storage processes

The effect of an interfacial polyelectrolyte complex layer on the stability of multiple water-in-oil-in-water (W/O/W) emulsions containing palm oil (oil phase) was investigated. Monodisperse W/O/W emulsions prepared by primary ultrasonic emulsification using polyglycerin polycondensed ricinoleic acid ester as an oil-soluble emulsifier followed by secondary microchannel emulsification contained multiple sodium caseinate-stabilized droplets with a mean diameter of 44 μm. The multiple droplets containing palm oil maintained their diameter at 60 °C for a minimum of 24 h, whereas significant aggregation of the multiple droplets, with a partially crystallized palm oil phase, was observed below its crystallization temperature (∼27 °C). The formation of a chitosan-sodium caseinate complex layer by the electrostatic interaction of positively charged chitosan with negatively charged sodium caseinate at the oil–water interface could suppress the aggregation of the multiple droplets, even below the crystallization temperature of palm oil. Calcein, a water-soluble fluorescent dye, was stably encapsulated for a month with a high entrapment yield at 25 °C with a chitosan-sodium caseinate complex layer, although without the complex layer, it leaked to the external water phase within a day. The W/O/W emulsion with the polyelectrolyte complex layer improved both the droplet dispersibility and encapsulation efficiency of the multiple droplets during heating at 80 °C, followed by cooling at 25 °C. Polarized microscopic observations indicated that the chitosan-sodium caseinate complex layer affected the crystallization of palm oil in multiple droplets: partial crystallization of palm oil in the multiple droplets may be delayed by the presence of the polyelectrolyte complex layer at the oil–water interface.

Efficient removal of antimony by a facile liquid-controlled strategy reinforced hematite-spinel (Fe2O3-MnFe2O4) composite: construction, simulation and practical evaluation

Currently, aqueous antimony contamination has become a non-negligible issue due to its scale industrious production and potential health risk. Herein, we prepare a novel hematite-spinel (Fe2O3-MnFe2O4) adsorbent by a one-step hydrothermal method for aqueous antimony deep purification, in which interfacial Fe-Mn bidentate complex sites are determined as the reinforced one by X-ray absorption spectroscopy (XAS) analysis and density functional theory (DFT) simulation. Through facile alkaline control by NH3·H2O and Fe/Mn proportion adjustment, the intrinsic synthesis kinetics of materials are precisely regulated that MnFe2O4 nano-particles successfully in-situ form on the Fe2O3 surface, in which sufficient adsorption sites are guaranteed by the small size effect. The adsorption experiment further demonstrates that the composite material is effective in Sb(III) and Sb(V) elimination, in which the adsorption capacity reaches up to 42.7 (Sb(III)) and 32.4 mg·g−1 (Sb(V)) (initial concentration 5.0 mg·L−1). The Sb K edge Extended X-ray absorption fine structure (EXAFS) analysis shows that antimony molecules occur as two typical complexation forms on the MnFe2O4 interface, in which an edge-sharing with Fe-O octahedron (Fe-Fe-ES) and two corner-sharing with Fe-O octahedron and Mn-O tetrahedron (Fe-Mn-CS) are exhibited. Further DFT calculations indicate that the Fe-Mn-CS has the highest adsorption energy for Sb(III) (-3.31 eV) and Sb(V) (-5.12 eV), which is rationally interpreted by the compatible overlapping of Fe 3d and O 2p as well as interfacial electron redistribution in Mn atom. This work may represent a new strategy in structure design and provide an alternative perspective in adsorption mechanism illustration.

Development of Heavy Element Chemistry at Interfaces: Observing Actinide Complexes at the Oil/Water Interface in Solvent Extraction by Nonlinear Vibrational Spectroscopy.

Understanding the chemistry of elements at the bottom of the periodic table is a challenging goal in chemistry. Observing actinide species at interfaces by using interface-selective second-order nonlinear optical spectroscopy, such as vibrational sum frequency generation (VSFG) spectroscopy, is a promising route for developing heavy element chemistry; however, such attempts are scarce. Here, we investigated the phase transfer mechanism of uranyl ions (UO22+) in solvent extraction using the di(2-ethylhexyl)phosphoric acid (HDEHP) extractant dissolved in the dodecane organic phase by probing the oil/water liquid–liquid interface using VSFG spectroscopy. The POO– symmetric stretch vibrational signals of the HDEHP ligands clearly demonstrated that uranyl ions form interfacial complexes with HDEHP at the oil/water interface. The interfacial uranyl–HDEHP complexes were formed with uranyl ions coming from both the aqueous and oil phases, strongly suggesting that the interfacial complex is an intermediate to cross the oil/water interface. Density functional theory calculations proposed the molecular structure of the interfacial uranyl–HDEHP complex.

Generation of interfacial high-spin manganese intermediates as reactive oxidant during peroxymonosulfate activation mediated by amorphous MnOx supported on polymeric substrate

The preparation of transition metal oxides based on traditional hydrothermal and calcination processes for heterogeneous PMS activation in contaminants' abatement has been widely reported. A satisfactory PMS activation efficiency often demands the transition metal oxides with crystallographic structure; however, the preparation processes of crystalline metal oxides require more energy input. Besides, achieving the targeted electron transfer between pollutants and reactive oxygen species (ROS) to overcome the disturbance of the actual water matrix is still challenging. Herein, we immobilized manganese oxides onto polymeric substrates under room temperature by a novel redox method with lower energy consumption. The obtained composite was applied for PMS activation to degrade multiple phenolic pollutants mainly through non-radical pathways. Combining the results of multiple characterizations and 18O isotope-tracer experiments, we proposed that the interfacial high-spin MnIII-peroxy complex was the primary reactive oxidant. Besides, a small portion of MnIII-peroxy complex could further undergo interspecies oxygen-transfer to form MnV-oxo species as the secondary reactive oxidant, resulting in the different manganese reduction products (MnIII/MnIV). The proposed mechanism could explain the average oxidation state of Mn changed after PMS activation. Comparing with the radical-based systems, interfacial reactive manganese intermediates exhibited satisfactory resistance against complex water matrices, such as chloride, bicarbonate, natural organic matter (NOM), and effluent organic matter (EfOM). We believe that this study could inspire novel methods with lower energy consumption to prepare active manganese oxides and provide intriguing mechanistic insights into PMS activation mediated by amorphous manganese oxides.

Influence of salt on the formation and separation of droplet interface bilayers

Phospholipid bilayers are a major component of the cell membrane that is in contact with physiological electrolyte solutions including salt ions. The effect of salt on the phospholipid bilayer mechanics is an active research area due to its implications for cellular function and viability. In this manuscript, we utilize droplet interface bilayers (DIBs), a bilayer formed artificially between two aqueous droplets, to unravel the bilayer formation and separation mechanics with a combination of experiments and numerical modeling under the effects of K+, Na+, Li+, Ca2+, and Mg2+. Initially, we measured the interfacial tension and the interfacial complex viscosity of lipid monolayers at a flat oil–aqueous interface and show that both properties are sensitive to salt concentration, ion size, and valency. Subsequently, we measured DIB formation rates and show that the characteristic bilayer formation velocity scales with the ratio of the interfacial tension to the interfacial viscosity. Next, we subjected the system to a step strain by separating the drops in a stepwise manner. By tracking the evolution of the bilayer contact angle and radius, we show that salt influences the bilayer separation mechanics, including the decay of the contact angle, the decay of the bilayer radius, and the corresponding relaxation time. Finally, we explain the salt effect on the observed bilayer separation by means of a mathematical model comprising the Young–Laplace and evolution equations.

A low cost and green curcumin/ZnO nanocomposites: Preparation, characterization and photocatalytic aspects in removal of amaranth dye and hydrogen evolution generation

Curcumin is natural non-toxic yellow pigment with potent biological and chemical reactivity due to the existence of keto-enol chemical structure. Incorporation of curcumin on ZnO surface enhances the absorbability of visible light radiations and increases the redox power of the charge carriers, In this research, curcumin/ZnO nanoparticles are generated for efficient decomposition of anionic amaranth dye and production of hydrogen gas as renewable fuel resource. ZnO nanoparticles were synthesized through sol-gel concepts by controlled hydrolysis of zinc acetylacetonate in presence of pluronic template. Curcumin with various concentration [1–5] wt% are deposited on ZnO nanoparticles in ultrasonic bath of 200 W intensity. The solid specimens are well explored by XRD, adsorption isotherms of nitrogen at 77K, HRTEM, XPS, DRS and PL. Curcumin molecules are interacted chemically with ZnO nanoparticles through interfacial charge transfer complex that improves the visible light harvesting and enhances the efficiency of the charge carriers separation. In solar reactor, ZnO with 3 wt % curcumin decomposes 95% of amaranth dye and produce hydrogen gas with evolution rate 5.1 mmolg−1hr−1. Depend on step S-scheme charge migration route, the positive hole and negative electrons in the valence band and LUMO energy level of ZnO and curcumin, respectively exerts a strong oxidative and reductive efficiency for the photocatalytic processes. The trapping experiments reveal that superoxide, positive holes and hydroxyl radicals are generated for rapid decomposition of amaranth dye. The durability and high photocatalytic performance of this novel nanocomposites can be used in various industrial and environmental purposes.

Dynamic interaction between complex defect and crack in functionally graded magnetic-electro-elastic bi-materials

This paper aims to develop an effective theoretical method for analyzing the interaction of interfacial crack and complex defect in functionally graded magnetic-electro-elastic bi-materials with exponential variation under the action of anti-plane incident SH-wave. The boundary value problem of interest is solved by Green’s function method. The mechanical model of the cracks is constructed through interface conjunction and crack deviation techniques, thereby simplifying the crack problem to solving a series of the first kind of Fredholm’s integral equations, from which the dynamic stress intensity factor (DSIF) at the crack tips of the left crack are expressed. The validity of the present method is verified by comparing with a single crack model in previous work. Through the analyses of numerical cases, it can be concluded that the DSIF is related with 3 factors：the geometry of complex defect and crack, the characteristics of incident wave and the inhomogeneity of materials. Comparing with dual integral equations in dealing with asymmetric defects, the method in this paper is relatively more flexible and applicable, also it comes up with a new way to study fracture problems in functionally graded magnetic-electro-elastic materials with more complex defects.

Interfacial Charge Transfer Complexes in TiO2-Enediol Hybrids Synthesized by Sol-Gel.

Metal oxide-organic hybrid semiconductors exhibit specific properties depending not only on their composition but also on the synthesis procedure, and particularly on the functionalization method, determining the interaction between the two components. Surface adsorption is the most common way to prepare organic-modified metal oxides. Here a simple sol–gel route is described as an alternative, finely controlled strategy to synthesize titanium oxide-based materials containing organic molecules coordinated to the metal. The effect of the molecular structure of the ligands on the surface properties of the hybrids is studied using three enediols able to form charge transfer complexes: catechol, dopamine, and ascorbic acid. For each system, the process conditions driving the transition from the sol to chemical, physical, or particulate gels are explored. The structural, optical, and photoelectrochemical characterization of the amorphous hybrid materials shows analogies and differences related to the organic component. In particular, electron paramagnetic resonance (EPR) spectroscopy at room temperature reveals the presence of organic radical species with different evolution and stability, and photocurrent measurements prove the effective photosensitization of TiO2 in the visible range induced by interfacial ligand-to-metal charge transfer.

Interfacial charge transfer complex formation between silver nanoparticles and aromatic amino acids.

The optical properties of surface-modified silver nanoparticles (Ag NPs) with aromatic amino acids tryptophan (Trp) and histidine (His) were examined using the cluster model for density functional theory (DFT) and time-dependent density functional theory (TD-DFT) calculations. Also, the redistribution of electronic charges upon chemisorption of ligand molecules onto silver's surfaces is determined. The obtained theoretical data, on one side, undoubtedly indicate the the formation of an interfacial charge transfer (ICT) complex between silver and this type of ligand, and, on the other side, partial oxidation of surface silver atoms accompanied by an increase of electron density in ligand molecules. The ICT complex formation, based on noble metal nanoparticles, has never been reported previously to the best of our knowledge. The experimental spectroscopic measurements support the theoretical data. A new absorption band in the visible spectral range appears upon surface modification of Ag NPs, and, when exposed to air, oxidation of surface-modified Ag NPs is significantly faster than the oxidation of the unmodified ones.

Lightweight PPy aerogel adopted with Co and SiO2 nanoparticles for enhanced electromagnetic wave absorption

Lightweight nanocomposites consisting of magnetic and dielectric units aroused intensive interest as potential high performance electromagnetic wave absorbing materials. In this work, we report a facile and efficient method to fabricate (Co, SiO2)/PPy composites with tunable electromagnetic properties. The absorbing properties and effective absorbing bandwidth can be regulated by controlling the content of SiO2 in composites. The composite shows a maximum reflection loss (RL) of -65.31 dB at 11.12 GHz with a thickness of 3.002 mm when SiO2 being 22 wt.%. The effective absorbing bandwidth reaches up to 5.1 GHz (8.91–14.01 GHz), which covers the entire X band (8–12 GHz). The improved impedance matching, high interfacial polarization and complex electromagnetic synergy in the composites are the key factors giving rise to the higher efficient absorption. The PPy aerogel-based nanocomposites with controllable absorption performance, lower density and strong environmental adaptability will become attractive candidates as advanced microwave absorbing materials.

Engineering novel surface electronic states via complex supramolecular tessellations

Interfacial complex supramolecular tessellations were employed to derive novel two-dimensional electronic structures from Shockley surface-state, giving rise to Kagome or Dirac bands as well as hybrid band structures through quantum dots coupling.

Interfacial Polyelectrolyte-Surfactant Complexes Regulate Escape of Microdroplets Elastically Trapped in Thermotropic Liquid Crystals.

Polyelectrolytes adsorbed at soft interfaces are used in contexts such as materials synthesis, stabilization of emulsions, and control of rheology. Here, we explore how polyelectrolyte adsorption to aqueous interfaces of thermotropic liquid crystals (LCs) influences surfactant-stabilized aqueous microdroplets that are elastically trapped within the LCs. We find that adsorption of poly(diallyldimethylammonium chloride) (PDDA) to the interface of a nematic phase of 4-cyano-4'-pentylbiphenyl (5CB) triggers the ejection of microdroplets decorated with sodium dodecylsulfate (SDS), consistent with an attractive electrical double layer interaction between the microdroplets and LC interface. The concentration of PDDA that triggers release of the microdroplets (millimolar), however, is three orders of magnitude higher than that which saturates the LC interfacial charge (micromolar). Observation of a transient reorientation of the LC during escape of microdroplets leads us to conclude that complexes of PDDA and SDS form at the LC interface and thereby regulate interfacial charge and microdroplet escape. Poly(sodium 4-styrenesulfonate) (PSS) also triggers escape of dodecyltrimethylammonium bromide (DTAB)-decorated aqueous microdroplets from 5CB with dynamics consistent with the formation of interfacial polyelectrolyte-surfactant complexes. In contrast to PDDA-SDS, however, we do not observe a transient reorientation of the LC when using PSS-DTAB, reflecting weak association of DTAB and PSS and slow kinetics of formation of PSS-DTAB complexes. Our results reveal the central role of polyelectrolyte-surfactant dynamics in regulating the escape of the microdroplets and, more broadly, that LCs offer the basis of a novel probe of the structure and properties of polyelectrolyte-surfactant complexes at interfaces. We demonstrate the utility of these new insights by triggering the ejection of microdroplets from LCs using peptide-polymer amphiphiles that switch their net charge upon being processed by enzymes. Overall, our results provide fresh insight into the formation of polyelectrolyte-surfactant complexes at aqueous-LC interfaces and new principles for the design of responsive soft matter.

Interfacial charge transfer complex between TiO2 and non-aromatic ligand squaric acid

The attachment of squaric acid, a non-aromatic molecule, to the surface of TiO2 powder induced the optical absorption of the obtained hybrid material in the visible spectral range due to the interfacial charge transfer complex formation. The optical characterization of the hybrid is supported by the density functional theory calculations of the model cluster. The paramagnetic species generated upon excitation with ultraviolet or visible light, in both TiO2 powders, pristine and surface-modified, were identified conducting low-temperature solid-state and indirect electron paramagnetic resonance (EPR) spectroscopy experiments (spin trapping and spin scavenging). The solid-state EPR experiments indicated the promotion of electrons from the organic moiety to the titania conduction band under visible-light excitation of hybrid. Also, the spin scavenging experiments showed that the electrons generated in the hybrid upon the visible-light activation facilitate the reduction of the radical cations present in the dispersion, while these effects are not observed for pristine TiO2.