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Designing plasmonic nanoparticles for biomedical photoacoustic (PA) imaging involves tailoring material properties at the nanometer scale. A key in developing plasmonic PA contrast nanoagents is to engineer their enhanced optical responses in the near‐infrared wavelength range, as well as heat transfer properties and photostability. This study introduces anisotropic plasmonic nanosphere aggregates with close interparticle proximity as photostable and efficient contrast agents for PA imaging. Silver (Ag) is particularly attractive because it has the strongest optical response and highest heat conductivity among plasmonic metals. The results demonstrate that close interparticle proximity in silver nanoaggregates (AgNAs), spatially confined within a polymer shell layer, leads to blackbody‐like optical absorption, resulting in robust PA signals through efficient pulsed heat generation and transfer. Additionally, the AgNAs exhibit a high photodamage threshold highlighting their potential to outperform conventional plasmonic contrast agents for high‐contrast PA imaging over multiple imaging sessions. Furthermore, the capability of the AgNAs are demonstrated for molecular PA cancer imaging in vivo by incorporating a tumor‐targeting peptide moiety. [ABSTRACT FROM AUTHOR]

Recently, electrochemical capacitor diodes (CAPodes) have been introduced as a new type of capacitive diode analogues. This device realizes unidirectional charging of ultracapacitors based on ion sieving mechanisms. Here, a new redox CAPode system is presented in which hydroxide ions react with nickel bismuth sulfide on nickel foam as a battery‐like electrode. This redox reaction leads to a high capacitance in a specific polarization window. However, for reversed bias this Faradaic electrode becomes inactive as it does not react with potassium cations, resulting in efficient blocking. By adapting counter electrode materials, mass loading, utilized substrates, and electrolyte concentrations a very high rectification ratio (RI = 37 and RII = 0.96 at 10 mV s−1) is achieved, significantly surpassing the performance of other reported redox‐type CAPodes. Moreover, this system shows an outstanding long‐term stability of a rectification retention of 90% for RII over 5000 repolarization cycles. Additionally, operando electrochemical measurements provide deep insights into the charge/discharge mechanism leading to a rationalization of the proposed concept. The integrated device, tested in logic gate circuits such as AND and OR gates, shows prospective results in ionologic applications. [ABSTRACT FROM AUTHOR]

Receptors are lipid bilayer‐resident molecules that perform a myriad of functions in a cell, from recognition to signaling and solute internalization, and are typically based on proteins. Herein, artificial receptors are engineered based on small organic molecules, toward chemical, non‐genetic engineering of cells. Specifically, artificial internalizing receptors are designed for selective targeting and cell‐specific drug delivery. The artificial receptors are shown to afford nanomolar potency of action for the cognate antibody‐drug conjugates. In the chemically engineered cells, the conjugate activity is at the same time more potent and significantly faster than that observed with the use of the pristine drug. In a mixed cell population, an antibody‐drug conjugate targeted to the artificial receptor can selectively eliminate the chemical receptor‐engineered cells. Taken together, these results illustrate that artificial receptors based on small organic molecules are simple by structure but can mediate one of the foundational cellular functions, namely endocytosis, with excellence. Most importantly, these receptors are truly bio‐orthogonal and thus afford a dedicated route of communication with the chemically engineered cells. [ABSTRACT FROM AUTHOR]

Targeted protein degradation (TPD) is a powerful technique for the regulation of protein homeostasis. Current TPD mainly focuses on the therapeutical consequences rather than the operation processes of the molecular tools. Herein, a platform for precise manipulation of the protein degradation by activatable lysosome targeting DNA nanodevices is constructed. In the design, a lysosome‐targeting CD63 aptamer is locked by the single‐stranded DNA with a photocleavable group and a disulfide bond. This locked CD63 aptamer is connected with the aptamer targeting the protein of interest via double‐stranded DNA linkages to form the logic‐gate activated lysosome targeting DNA nanodevice (LALTD). With the UV light and endogenous GSH as inputs, an AND logic gate is built to efficiently manipulate the protein delivery processes by LALTD. The protein of interest can be degraded via efficient lysosome hydrolysis. Further studies show that the logic‐gate operation can be used for modulating T cell‐mediated antitumor immunity. The modularly designed activatable lysosome targeting DNA nanodevices exhibits good stability, controllability, programmability, and universality, providing a new prospect for accurate protein degradation and precise therapy. [ABSTRACT FROM AUTHOR]

Sonosensitizers in current sonodynamic therapy (SDT) often suffer from poor delivery efficiency, phototoxicity, and disputed safety. To overcome these issues, a sonosensitizers‐free sonocatalytic nanomissile is constructed, wherein PLGA nanoparticles as vehicles conjugate with L‐arginine (LA) and aptamer XQ2d capable of adsorbing CO2 and targeting CD71‐overexpressed pancreatic cancer, respectively. The adsorbed CO2 can respond to acidic tumor microenvironment and local ultrasound to release CO2 bubbles and enhance ultrasound‐triggered inertial cavitation, which can further split H2O and activate dissolved O2 to produce ·OH and 1O2, respectively, unlocking the sonosensitizers‐free sonocatalytic ROS birth. Moreover, such CO2 bubbles‐enhanced inertial cavitation also can target intratumoral vascular destruction, instigate thrombus aggregation, induce nutrition and oxygen deprivation, pose hypoxia and alter tumor metabolism, thus establishing an intratumoral vascular destruction‐targeted starvation therapy. The strategy is different from previous starvation therapy in which the presence of undamaged intratumoral blood vessels compromises their outcomes. Especially, the active targeting aptamer XQ2d allows more sonosensitizer‐free sonocatalytic nanomissiles to retain in pancreatic cancer, significantly magnifying the sonosensitizers‐free sonocatalytic therapy and starvation therapy against subcutaneous and orthotopic pancreatic cancers. Therefore, the research provides a promising route and therapeutic platform for clinical pancreatic cancer therapy. [ABSTRACT FROM AUTHOR]

Though urgently needed, high‐efficiency near‐infrared (NIR) organic light‐emitting diode (OLED) is still rare due to the energy‐gap law. Formation of intermolecular charge‐transfer aggregates (CTA) with nonadiabatic coupling suppression can decelerate non‐radiative decay rates for high‐efficiency NIR‐OLEDs. However, the aggregation effect of CTA is still not fully understood, which limits the rational design of CTA. Herein, two CTA molecules with a same π‐framework but different terminal substituents are developed to unveil the aggregation effect. In highly ordered crystalline states, the terminal substituents substantially affect the molecular packing motifs and intermolecular charge‐transfer states, thus leading to distinct photophysical properties. In comparison, in amorphous states, these two CTA demonstrate similar photophysical behaviors and properties due to their similar molecular packing and intermolecular interactions as evidenced by molecular dynamics simulations. Importantly, the formations of amorphous CTA trigger multifunction improvements such as aggregation‐induced NIR emission, aggregation‐induced thermally activated delayed fluorescence, self‐doping and self‐host features. The non‐doped OLEDs demonstrate NIR emissions centered at 788 and 803 nm, and high maximum external quantum efficiencies of 2.6% and 1.5% with small efficiency roll‐off, respectively. This study provides deeper insight into the aggregation effect of CTA and lays a foundation for the development of high‐efficiency NIR non‐doped OLEDs. [ABSTRACT FROM AUTHOR]

In an endeavor to understand why the dissociation of charge‐transfer (CT) states in a PM6:Y6 solar‐cell is not a thermally activated process, measurements of energy‐resolved impedance as well as of intrinsic photoconduction are employed. This study determines the density of states distributions of the pertinent HOMO and LUMO states and obtains a Coulomb binding energy (Eb,CT) of ≈150 meV. This is 250 meV lower than the value expected for a pair of localized charges with 1 nm separation. The reason is that the hole is delocalized in the polymer and the electron is shared among Y6 molecules forming a J‐like aggregate. There are two key reasons why this binding energy of the CT state is not reflected in the temperature dependence of the photocurrent of PM6:Y6‐diode: i) The e–h dissociation in a disordered system is a multi‐step process whose activation energy is principally different from the binding energy of the CT state and can be substantially less than Eb,CT, and ii) since dissociation of the CT state competes with its intrinsic decay, the dissociation yield saturates once the rate of dissociation grossly exceeds the rate of intrinsic decay. This study argues that these conditions are met in a PM6:Y6‐solar cell. [ABSTRACT FROM AUTHOR]

Polysilsesquioxanes (PSQs) have generated great interest as solution‐processable inorganic polymers for obtaining high‐dielectric‐constant (k) dielectrics. Engineering the side chains in PSQs can enhance the polarization characteristics and provide different functionalities, such as photopatternability and ferroelectric performance. In this study, two types of UV curable high‐k PSQs are prepared by introducing epoxy‐containing side chains to the PSQs: 1) glycidyl epoxy‐containing linear groups and 2) bulky cycloaliphatic epoxy‐containing groups. The physical, chemical, and electrical properties of these two materials after UV curing are investigated. Both PSQ films show high dielectric strength and are successfully patterned after exposure to UV light. The structure of the side chains influences the UV curing behavior and capacitance characteristics of the PSQ dielectrics. These differences determine the driving behavior of the fabricated organic thin‐film transistors, which exhibits either stable or ferroelectric operation. Finally, logic gates and memory cells exhibiting low‐voltage and non‐destructive operations are successfully integrated using UV cured PSQs. This approach for engineering PSQs with the purpose of achieving desirable photopatternability and high dielectric or ferroelectric performance can be used to realize simple and inexpensive solution‐processing techniques for next generation integrated electronics. [ABSTRACT FROM AUTHOR]

Precise delivery and release of therapeutics in the subcellular targets are critical for tumor‐selective chemotherapy. Self‐immolative structures are sophisticatedly designed to achieve stimuli‐responsive drug delivery. Herein, the facile fabrication of self‐immolative peptide‐camptothecin (CPT) nanoassemblies is reported for cancer‐selective drug delivery by utilizing the dual‐mode peptide targeting design and amine‐catalyzed intramolecular hydrolysis. The dual‐mode peptide targeting design is realized by co‐assembly of tumor targeting and nuclei‐localizing peptide‐CPT prodrugs, rendering the nanoassemblies with efficient cancer cell‐selective capability. When the nanoassemblies enter cancer cell, the overexpressed endonuclear histone deacetylases (HDACs) cleave the acetyl group to generate primary amines, triggers amine‐catalyzed intramolecular hydrolysis, and fast‐release drug in the cell nuclei. The peptide‐CPT prodrugs release up to 68% CPT in 1 h in the presence of HDACs, while no detectable CPT release is observed in the absence of HDACs at the same time. The peptide‐CPT prodrugs selectively kill cancer cells with high HDACs levels. The dual targeting peptide‐CPT nanoassemblies exhibit extended blood circulation, excellent tumor accumulation, and potent antitumor activity by inhibiting tumor progression and metastasis in mice bearing 4T1 aggressive breast tumors. Overall, the HDAC‐triggered self‐immolative strategy is promising for developing cancer‐selective drug delivery systems. [ABSTRACT FROM AUTHOR]

Natural biotissues like muscles, ligaments, and nerves have highly aligned structures, which play critical roles in directional signal transport, sensing, and actuation. Inspired by anisotropic biotissues, composite hydrogels with outstanding mechanical properties and conductivity are developed by compositing thermo‐responsive poly (N‐isopropylacrylamide) (PNIPAM) hydrogels with highly aligned carbon fibers (CFs). The anisotropic hydrogels show superior tensile strength (3.0 ± 0.3), modulus (74 ± 7.0 MPa), excellent electrical conductivity (≈670 S m−1), and ultra‐high sensitivity (gauge factor up to 647) along CFs, with an anisotropic ratio (AR) up to 740 over those in perpendicular direction. The extremely high AR in conductivity (more than 400) produces high‐level output in parallel direction and low‐level output in perpendicular direction with a direct current (DC) power supply, which is used to fabricate AND and OR gates. Moreover, the composite hydrogels are converted into thermo‐responsive actuators with CFs twisted before compositing with PNIPAM/clay network. The pre‐twisted CF helices impart internal stress that drives reversible actuation of hydrogel helices upon thermo‐stimulating. The actuation is self‐sensed due to the extremely high sensitivity of the composite hydrogels. Such biomimetic anisotropic self‐sensing hydrogel actuators resemble natural biotissues with both actuation and sensing capabilities, and have promise applications for artificial robotics. [ABSTRACT FROM AUTHOR]

The photophysical properties of pure organic materials in solid‐state are widely related to the crystal's arrangements. Herein, 4,6‐bis((E)‐4‐(dibenzothiophene)styryl)‐5(ethoxycarbonyl)‐2,2‐difluoro‐2H‐1,3,2‐dioxaborinin‐1‐ium‐2‐uide (BBSF) is employed as a mode molecule to explore the relationship between molecular arrangement and performance. Three elegant crystals (solvent‐free‐J‐aggregation of EA‐crystal, solvent‐J‐aggregations of CB‐crystal, and FB‐crystal) are obtained by solvato‐tailored strategy. Detailed single crystal structures and photophysical data reveal that all the three crystals adopt a J‐type aggregation model. EA‐crystal does not involve solvent molecular while the CB‐ and FB‐crystals involve chlorobenzene (CB) and fluorobenzene (FB) molecules, respectively. Solvent molecules can effectively separate the two columns of BBSF molecules, resulting in high brightness emission. Laser behaviors indicate that the solvent‐microcrystals display higher brightness, lower threshold, as well as higher quality factor than solvent‐free‐microcrystal due to the weakened bimolecular exciton annihilation process. This strategy not only paves an intriguing way to the construction and preparation of pure organic J‐aggregation laser materials but also offers a guideline for suppressing bmEA process through introducing solvent molecules. [ABSTRACT FROM AUTHOR]

Bioinspired electronics have shown great potential in the field of artificial intelligence and brain‐like science. Low energy consumption and multifunction are key factors for its application. Here, multisensory artificial synapse and neural networks based on electrolyte‐gated vertical organic field‐effect transistors (VOFETs) are first developed. The channel length of the organic transistor is scaled down to 30 nm through cross‐linking strategy. Owing to the short channel length and extremely large capacitance of the electric double layer formed at the electrolyte–channel interface, the minimum power consumption of one synaptic event is 0.06 fJ, which is significantly lower than that required by biological synapses (1–10 fJ). Moreover, the artificial synapse can be trained to learn and memory images in a 5 × 5 synapse array and emulate the human brain's spatiotemporal information processing and sound azimuth detection. Finally, the artificial tongue is designed using the synaptic transistor that can discriminate acidity. Overall, this study provides new insights into realizing energy‐efficient artificial synapses and mimicking biological sensory systems. [ABSTRACT FROM AUTHOR]

Natural photosynthetic photonic nanostructures can show sophisticated light–matter interactions including enhanced light absorption by slow light even for highly pigmented systems. Beyond fundamental biology aspects, these natural nanostructures are very attractive as blueprints for advanced photonic devices. But the soft‐matter biomimetic implementations of such nanostructures is challenging due to the low refractive index contrast of most organic photonic structures. Excitonic organic materials with near‐zero index (NZI) optical properties allow overcoming these bottlenecks. Here, it is demonstrated that the combination of NZI thin films with photonic multilayers like the ones found in nature enables broadband tunable strong reflectance as well as slow light absorption enhancement and tailored photoluminescence properties in the full VIS spectrum. Moreover, it is shown that this complex optical response is tunable, paving the way toward the development of active devices based on all‐polymer and near‐zero index materials photonic structures. [ABSTRACT FROM AUTHOR]

Herein, it is reported the influence of solution processing and treatments, such as adding marginal solvent, ultrasonication, and UV treatment, on the resulting perovskite (CsPbBr3) quantum dot (QD)/poly(3‐hexylthiophene) (P3HT) composite nanofibril films (CNFs) to improve the charge dissociation and photonic synaptic performance. A photonic synaptic transistor with CNFs can perform fundamental functions, including short‐term plasticity, long‐term plasticity, spike‐number‐dependent, and spike‐time‐dependent plasticity, to mimic sensing, computing, and memory functions. Notably, a synaptic device with CNFs presents an ultralow energy consumption of 0.18 fJ and zero‐gate operation. The superior performance of synaptic devices with CNFs can be attributed to two factors: (i) homogeneous axial distribution of the QDs and (ii) the formation of P3HT nanofibrils and co‐aggregates. Therefore, enhanced interfacial charge transfer between QDs and P3HT, ensuring decent carrier transport capability, is achieved. Collectively, the composite artificial synapse successfully provides an effective guide that offers a new perspective for the fabrication of one‐dimensional self‐assembled nanostructure‐based artificial synapses emulating human‐like memory, neuromorphic computing, and artificial intelligent systems. [ABSTRACT FROM AUTHOR]

Progress in the development and clinical efficacy of antibody‐drug conjugates (ADCs) has attracted the interests of both academic researchers and the industry. The rationale for developing ADCs is based on the inherent non‐selectivity of chemotherapy for tumor cells, leading to side effects that can be severe and life threatening. Another major consequence of chemotherapy is the development of drug resistance. For these reasons, targeted drug delivery (TDD) systems are being developed to specifically deliver the cytotoxic drug into the target cell. A variety of carriers that can deliver drugs to the surface or into cancer cells, one of which is the use of monoclonal antibodies, with to date ten ADCs having received FDA approval. This review will focus on the development and clinical application of five ADCs currently approved for the treatment of hematological malignancies. Following a short history that led to their regulatory approval, the review will focus on the important link between the biology of the ADC, the cell surface component targeted by the antibody component, and clinical efficacy and conclude by highlighting newer developments that strengthen this link, so that ADCs can provide long‐term clinical benefit to patients with hematological cancers. [ABSTRACT FROM AUTHOR]

As a non‐invasive treatment modality, photodynamic therapy has been a potential therapeutic method for metastatic and non‐metastatic tumors. In order to further improve the tumor selectivity, phtotoimmunotherapy (PIT) has been developed recently, which includes antibodies as the active targeting ligands. However, traditional monoclonal antibody‐based PIT suffers from long half‐lives and extended phototoxic side‐effects in vivo. Herein, a type I mechanism‐based photoimmunoconjugate (PIC) is developed by incorporating anti‐EGFR nanobody as the targeting ligand, and benzophenothiazine as the photosensitizer (PS). The small size and robust structure of the nanobody ensures excellent targeting accuracy and efficient renal excretion. Meanwhile, the type I PS is able to circularly transfer oxygen to superoxide radical upon irradiation to overcome hypoxia microenvironment. The PIC showed satisfying phototherapeutic ability both in normoxia and hypoxia, and displayed high selectivity towards tumor in vivo. By combining nanobody and Type I PS, the work presents a novel type of PIC for the precise treatment of tumors with high specificity and potency. [ABSTRACT FROM AUTHOR]

Optical microcavities confine molecular luminescence and transfer it to a far longer distance than the conventional Förster resonant energy transfer process. Such cavity‐mediated energy transfer is advantageous for use in optical circuitry. However, to realize all‐organic optical circuits, optical gate operation with organic materials is indispensable. Here, all‐organic optical gates consisting of polymer whispering gallery mode (WGM) resonators that work as the optical source, drain, and gate, which are interconnected with polymer microfiber, are demonstrated. Photoirradiation of the source sphere, as an optical input, triggers the blue fluorescence that transmits to the gate sphere through the fiber. The fiber interconnection enhances both the light confinement efficiency in the individual spheres and the light transmission efficiency between distant spheres. The gate sphere contains photoisomerizable fluorescent dye that converts, in its closed state, the blue emission into green light, which is again transmitted to the drain sphere through the fiber and lets the sphere emit red light as an output. This optical cascade is switched on and off upon photoisomerization of the dye in the gate sphere. Furthermore, an energy cascade equipped with two gate spheres works as an OR‐type logic gate, demonstrating potential utility for the future all‐organic and all‐optical integrated devices. [ABSTRACT FROM AUTHOR]

Medical implants are widely used in clinical practice, such as cardiovascular stenting, maxillofacial surgery, and orthopedics. However, most of the traditional implant operations are open and invasive, resulting in massive dissection of soft tissue and interruption of blood supply. The accurate navigation for the implant operations is considered as one of the most effective ways to reduce the damage, which is urgently desired in clinic. Herein, a biocompatible NIR‐II J‐aggregates labelled mesoporous implant for imaging‐guided osteosynthesis with minimal invasion is reported. Mesoporous silica layer with vertical channels is grown on the surface of titanium plate, which can provide the confining space for the formation of the FD‐1080 J‐aggregates. Both the absorption and fluorescence peaks of the FD‐1080 J‐aggregates are located in NIR‐II window (beyond 1300 nm), which are ideal for high resolution and real time surgical navigation in deep tissue. NIR‐II imaging can clearly display the location and outline of the implant both in vitro and in vivo. This NIR‐II imaging‐guided osteosynthesis can effectively reduce the surgical wound and operational duration, which is crucial for the implant surgeries. [ABSTRACT FROM AUTHOR]

The J‐aggregation of dye‐functional group conjugates, which results in intriguing photophysical properties and highly ordered structures, has several advantages over that of monomeric dyes and exhibits augmented performance compared to that of monomeric functional groups, thereby providing a novel platform for devising materials with advanced functions. Herein, it is reported that a molecularly engineered nanodisc by the antiparallel J‐aggregation of halogenated BODIPY‐Gd(III), a dye‐functional group conjugate. The highly directional halogen‐bonding interactions enable a unique antiparallel J‐stacking of BODIPY‐Gd(III), resulting in an alternating, orderly arrangement of the functional Gd(III) groups on the surfaces of the nanodisc, and allowing water stability and an enhanced magnetic resonance signal. Moreover, the J‐stacked dyes render the nanodisc with excellent photothermal performance, such as intense NIR‐absorptivity, high photothermal conversion efficiency, and a nearly non‐photobleaching capability. Preliminary in vivo studies demonstrated the potential of the nanodisc as an efficient bimodal photoacoustic and high‐performing magnetic resonance imaging, and antitumor photothermal therapy agent. This conceptual work not only establishes a general strategy for nano‐J‐aggregates with desired dye arrangement, controlled size, and in vivo stability, but also advances the antiparallel J‐aggregation of dye‐functional group conjugates as a potential platform for multifunctional integration and modulation, wherein multiple functional groups and BODIPYs can be installed. [ABSTRACT FROM AUTHOR]

Natural polymers, such as polysaccharides and proteins, have been widely studied for numerous biomedical applications because of their bioactivity, natural origin, and biodegradability. To address the different needs of a broad spectrum of biomedical applications, natural polymers are modified with or conjugated to small molecular compounds, synthetic and natural polymers, and inorganic nanomaterials and surfaces. Among these hybrid materials, polysaccharide–peptide conjugates have drawn much attention due to their design flexibility, biocompatibility, tunable degradability, and structure similarity to naturally occurring glycoproteins. In the past 20 years, polysaccharide–peptide conjugates have demonstrated the promising potential to address many long‐standing medical challenges. Thus, the design, conjugation chemistry and method, and biomedical applications of polysaccharide–peptide conjugates are summarized and discussed in this review. The conjugation techniques are reviewed from the view of the chemical reactions. Meanwhile, some inspiring examples of polysaccharide–peptide conjugates in biomedical applications, including drug delivery systems, nucleic acid delivery carriers, tissue engineering, and antimicrobial applications, are highlighted. Moreover, the outlook on the challenges and demands of polysaccharide–peptide conjugates is also elaborated. [ABSTRACT FROM AUTHOR]

Nanoparticle‐based nucleic acid conjugates (NP‐NACs) hold great promise for theragnostic applications. However, several limitations have hindered the realization of their full potential in the clinical treatment of cancer and other diseases. In diagnoses, NP‐NACs suffer from low signal‐to‐noise ratios, while the efficiency of NP‐NACs‐mediated cancer therapies has been limited by the adaptation of alternative prosurvival pathways in cancer cells. The recent emergence of personalized and precision medicine has outlined the importance of having both accurate diagnosis and efficient therapeutics in a single platform. As such, the controlled assembly of hybrid graphene oxide/gold nanoparticle (Au@GO NP)‐based cancer‐specific NACs (Au@GO NP‐NACs) for multimodal imaging and combined therapeutics is reported. The developed Au@GO NP‐NACs show excellent surface‐enhanced Raman scattering (SERS)‐mediated live‐cell cancer detection and multimodal synergistic cancer therapy through the use of photothermal, genetic, and chemotherapeutic strategies. Synergistic and selective killing of cancer cells are then demonstrated using in vitro microfluidic models. Moreover, with the distinctive advantages of the Au@GO NP‐NACs for cancer theragnostics, precision cancer treatment through the detection of cancer cells in vivo using SERS followed by efficient ablation of tumors is shown. Therefore, the Au@GO NP‐NACs can pave a new road for advanced disease theragnostics. [ABSTRACT FROM AUTHOR]

Advanced‐performance haptic systems, with high dynamic range (DR) and high pressure sensitivity, that accurately sense the small force variations with a wide detection range are essential for robotic systems, human‐machine interactions, and medical monitoring devices. However, existing skin‐like devices, such as capacitive or electrical transistor detectors, are limited by pressure contrast or recognition accuracy, thereby blocking the development of practical engineering. In the present study, an innovative pressure mapping interaction (PMI) based on dual piezo‐phototronic transistors (DPTs) is manufactured with the capability of detecting a large pressure gradient within a wide output range for providing more tactile details. The fabricated DPT, which integrates a piezo‐nanowire channel and a piezo‐OLED gate as one module with dual enhancements of the piezo‐phototronic effect, exhibits a high DR of ≈120 dB with ≈61.2 µS kPa−1 of pressure sensitivity in the effective working region. Furthermore, by employing the diminutive DPT as the PMI pixel, the device can obtain a high position resolution of 5 µm in the optimized array structure. The methods for designing and applying the PMI demonstrate effective processes for combining the piezo‐OLED gates and the piezo‐nanowire channels, which are responsible for improving the characteristics of the pressure‐relative electrical skin and others. [ABSTRACT FROM AUTHOR]

An artificial vision system that can simulate the visual functions of human eyes is required for biological robots. Here, In‐Ga‐Zn‐O memtransistors using a naturally oxidized Al2O3 and an ion gel as a common gate stacking dielectric is proposed. Positive charge trapping in the Al2O3 layer can be induced by modulating the gate voltage, which causes the back sweep subthreshold swing (SS) of the device to break the physical limit (≥60 mV per decade at room temperature), and the minimum SS is as low as 26.4 mV per decade. In addition, photogenerated charges in the device are captured at the In‐Ga‐Zn‐O channel/ion gel interface due to the superposition of the additional electric field generated by positive charges trapped in the Al2O3 layer and the external gate electric field. Thus, persistent photoconductivity is observed in the In‐Ga‐Zn‐O memtransistors. Finally, by employing the optoelectronic memristive functions of In‐Ga‐Zn‐O memtransistors, an artificial vision system based on artificial retinal array (ARA) and artificial neural network is proposed. An obvious improvement in the recognition rate and efficiency with the use of ARA for the image preprocessing is achieved. This study provides a new strategy for the realization of artificial vision systems. [ABSTRACT FROM AUTHOR]

An ideal cancer nanomedicine should precisely deliver therapeutics to its intracellular target within tumor cells. However, the multiple biological barriers seriously hinder their delivery efficiency, leading to unsatisfactory therapeutic outcome. Herein, pH/cathepsin B hierarchical‐responsive nanoconjugates (HRNs) are reported to overcome these barriers by sequentially responding to extra‐ and intracellular stimuli in solid tumors for programmed delivery of docetaxel (DTX). The HRNs have stable nanostructures (≈40 nm) in blood circulation for efficient tumor accumulation, while the tumor extracellular acidity induces the rapid dissociation of HRNs into polymer conjugates (≈5 nm), facilitating the deep tumor penetration and cellular internalization. After being trapped into the lysosomes, the conjugates are cleaved by cathepsin B to release bioactive DTX into cytoplasm and inhibit cell proliferation. In addition to the direct inhibition effect, HRNs can trigger the in vivo antitumor immune responses via the immunogenic modulation of tumor cells, activation of dendritic cells (DCs), and generation of cytotoxic T‐cell responses. By employing a combination with α‐PD‐1 (programmed cell death 1) therapy, synergistic antitumor efficacy is achieved in B16 expressing ovalbumin (B16OVA) tumor model. Hence, this strategy demonstrates high efficiency for precise intracellular delivery of chemotherapeutics and provides a potential clinical candidate for cancer chemo‐immunotherapy. [ABSTRACT FROM AUTHOR]

Tactile detection is a crucial technology in many fields, such as electronic skin, touch screen control, human prostheses, and screen fingerprint identification. Tribotronics has demonstrated active mechanosensation from external mechanical stimuli, which greatly enriches the sensing mechanisms of tactile detection. In this work, a monolithic integrated indium‐gallium‐zinc‐oxide (InGaZnO or IGZO) thin‐film transistor (TFT) array is developed for high‐resolution tactile detection. By using the conventional semiconductor fabrication processes, each IGZO TFT cell in the array shows uniform electrical performance. In addition, the drain–source current can be individually tuned by the electrostatic potential generated by the contact electrification between a movable gate and the gate dielectric. The monolithic integrated array displays a relatively high resolution of 12 pixels per inch and can realize a millimeter‐level tactile perception and motion tracking. This work presents a facile and viable strategy toward micro/nano‐scale tribotronics, which can realize high‐resolution and large‐scale tactile detection. [ABSTRACT FROM AUTHOR]

Recognition of oligosaccharides is associated with very limited specificity due to their strong solvation in water and the high degree of subtle structural variations between them. Here, oligosaccharide recognition sites are created on material surfaces with unmatched, binary on–off binding behavior, sharply discriminating a target oligosaccharide over closely related carbohydrate structures. The basis for the superselective binding behavior relies on the highly efficient generation of a pure, high order complex of the oligosaccharide target with synthetic carbohydrate receptor sites, in which the spatial arrangement of the multiple receptors in the complex is preserved upon material surface incorporation. The synthetic binding scaffolds can easily be tailored to recognize different oligosaccharides and glycoconjugates, opening up a realm of possibilities for their use in a wide field of applications, ranging from life sciences to diagnostics. [ABSTRACT FROM AUTHOR]

A facile, high‐resolution patterning process is introduced for fabrication of electrolyte‐gated transistors (EGTs) and circuits using a photo‐crosslinkable ion gel and stencil‐based screen printing. The photo‐crosslinkable gel is based on a triblock copolymer incorporating UV‐sensitive terminal azide functionality and a common ionic liquid. Using this material in conjunction with conventional photolithography and stenciling techniques, well‐defined 0.5–1 μm thick ion gel films are patterned on semiconductor channels as narrow as 10 μm. The resulting n‐type ZnO EGTs display high electron mobility (>2 cm2 Vs−1) and on/off current ratios (>105). Further, EGT‐based inverters exhibit static gains >23 at supply voltages below 3 V, and five‐stage EGT ring oscillator circuits display dynamic propagation delays of 50 μs per stage. In general, the screen printing and photo‐crosslinking strategy provides a clean room‐compatible method to fabricate EGT circuits with improved sensitivity (gain) and computational power (gain × oscillating frequency). Detailed device analysis indicates that significantly shorter delay times, of order 1 μs, can be obtained by improving the ion gel conductance. [ABSTRACT FROM AUTHOR]

Piezochromic fluorescent (PCF) materials with distinct multicolor switching have attracted wide attention in many fields such as optoelectronic devices and deformation detection. However, few PCF materials with low‐pressure stimuli and good recoverability have been reported. A highly sensitive and easily recoverable PCF molecular system that can switch between green (G) and orange (O) emissions upon an extremely low piezoresponsive (PR) of 0.5 MPa and heating at 120 °C is demonstrated. A mechanistic study combining X‐ray diffraction analysis and the theoretical calculations reveal that a slight change in slipping‐angle of π‐stacks induced by mechanical pressure amplifies the exciton couplings from G to O J‐aggregates, leading to not only distinct PCF switching but also high emission efficiencies >0.5 owing to superradiance of J‐aggregate excitons. Benefiting from low MPa PR, high emission efficiency, and good recoverability applications including haptic sensors and anti‐counterfeiting application are demonstrated. This research introduces the effect of stimuli‐responsive excitonic coupling as new design guidance for developing PCF materials with low‐pressure stimuli, high emission efficiency, and good recoverability. [ABSTRACT FROM AUTHOR]

Keywords: gate dielectrics; high dielectric constant; logic gates; low-voltage operation; memory device cells; polysilsesquioxanes EN gate dielectrics high dielectric constant logic gates low-voltage operation memory device cells polysilsesquioxanes 1 1 1 05/11/23 20230508 NES 230508 B Polysilsesquioxanes b In article number 2214865, Insik In, Yong Jin Jeong, Se Hyun Kim, and co-workers prepare two types of UV-curable high-dielectric-constant polysilsesquioxanes by introducing epoxy-containing side chains: 1) glycidyl epoxy-containing linear groups and 2) bulky cycloaliphatic epoxy-containing groups. The structure of the side chains influenced the UV curing behavior and capacitance characteristics of polysilsesquioxanes. Gate dielectrics, high dielectric constant, logic gates, low-voltage operation, memory device cells, polysilsesquioxanes. [Extracted from the article]

Abstract: Combination nanotherapies for the treatment of breast cancer permits synergistic drug targeting of multiple pathways. However, poor carrier degradability, poor synergism of the combined drugs, low drug release regulation, and a lack of control on final macromolecule solution conformation (which drives the biological fate) limit the application of this strategy. The present study describes the development of a family of drug delivery systems composed of chemotherapeutic (doxorubicin) and endocrine therapy (aromatase inhibitor aminoglutethimide) agents conjugated to a biodegradable poly‐ l‐glutamic acid backbone via various linking moieties. Data from in vitro cytotoxicity and drug release assessments and animal model validation select a conjugate family member with optimal biological performance. Exhaustive physicochemical characterization in relevant media (including the study of secondary structure, size measurements, and detailed small‐angle neutron scattering analysis) correlates biological data with the intrinsic supramolecular characteristics of the conjugate. Overall, this study demonstrates how a small flexible Gly linker can modify the spatial conformation of the entire polymer–drug conjugate, promote the synergistic release of both drugs, and significantly improve biological activity. These findings highlight the need for a deeper understanding of polymer–drug conjugates at supramolecular level to allow the design of more effective polymer–drug conjugates. [ABSTRACT FROM AUTHOR]

Abstract: In this study, room‐temperature mechanical rubbing is used to control the 3D orientation of small π‐conjugated molecular systems in solution‐processed polycrystalline thin films without using any alignment substrate. High absorption dichroic ratio and significant anisotropy in charge carrier mobilities (up to 130) measured in transistor configuration are obtained in rubbed organic films based on the ambipolar quinoidal quaterthiophene (QQT(CN)4). Moreover, a solvent vapor annealing treatment of the rubbed film is found to improve the optical and charge transport anisotropy due to an increased crystallinity. X‐ray diffraction and atomic force microscopy measurements demonstrate that rubbing does not only lead to an excellent 1D orientation of the QQT(CN)4 molecules over large areas but also modifies the orientation of the crystals, moving molecules from an edge‐on to a face‐on configuration. The reasons why a mechanical alignment technique can be used at room temperature for such a polycrystalline film are rationalized, by the plastic characteristics of the QQT(CN)4 layer and the role of the flexible alkyl side chains in the molecular packing. This nearly complete conversion from edge‐on to face‐on orientation by mechanical treatment in polycrystalline small‐molecule‐based thin films opens perspectives in terms of fundamental research and practical applications in organic optoelectronics. [ABSTRACT FROM AUTHOR]

Abstract: The huge information storage capability of DNA and its ability to self‐assemble can be harnessed to enable massively parallel computing in a small space. DNA‐based logic gates are designed that rely on DNA strand displacement reactions; however, computation is slow due to time‐consuming DNA reassembly processes and prone to failure as DNA is susceptible to degradation by nucleases and under certain solution conditions. Here, it is shown that the presence of a cationic copolymer boosts the speed of DNA logic gate operations that involve multiple and parallel strand displacement reactions. Two kinds of DNA molecular operations, one based on a translator gate and one on a seesaw gate, are successfully enhanced by the copolymer without tuning of computing conditions or DNA sequences. The copolymer markedly reduces operation times from hours to minutes. Moreover, the copolymer enhances nuclease resistance. [ABSTRACT FROM AUTHOR]

Abstract: Glucagon is a peptide hormone used for the treatment of hypoglycemia; however, its clinical potential is limited by its insolubility and instability in solution. Herein, the encapsulation, stabilization, and release of glucagon by trehalose glycopolymer nanogels are reported. Methacrylate‐functionalized trehalose is copolymerized with pyridyl disulfide ethyl methacrylate using free radical polymerization conditions to form trehalose glycopolymers with thiol‐reactive handles. Glucagon is chemically modified to contain two thiol groups and is subsequently utilized as the cross‐linker to form redox‐responsive trehalose nanogels with greater than 80% conjugation yield. Nanogel formation and subsequent glucagon stabilization are characterized using polyacrylamide gel electrophoresis, dynamic light scattering, and transmission electron microscopy. It is determined that the solution stability of the glucagon increased from less than 24 h to at least three weeks in the nanogel form. Additionally, in vitro activity of the synthesized glucagon analog and released glucagon is investigated, demonstrating that the glucagon remains active after modification. It is anticipated that these glucagon–nanogel conjugates will be useful as a stabilizing glucagon formulation, allowing for cargo release under mild reducing conditions. [ABSTRACT FROM AUTHOR]

Abstract: Glucagon is a peptide hormone used for the treatment of hypoglycemia; however, its clinical potential is limited by its insolubility and instability in solution. Herein, the encapsulation, stabilization, and release of glucagon by trehalose glycopolymer nanogels are reported. Methacrylate‐functionalized trehalose is copolymerized with pyridyl disulfide ethyl methacrylate using free radical polymerization conditions to form trehalose glycopolymers with thiol‐reactive handles. Glucagon is chemically modified to contain two thiol groups and is subsequently utilized as the cross‐linker to form redox‐responsive trehalose nanogels with greater than 80% conjugation yield. Nanogel formation and subsequent glucagon stabilization are characterized using polyacrylamide gel electrophoresis, dynamic light scattering, and transmission electron microscopy. It is determined that the solution stability of the glucagon increased from less than 24 h to at least three weeks in the nanogel form. Additionally, in vitro activity of the synthesized glucagon analog and released glucagon is investigated, demonstrating that the glucagon remains active after modification. It is anticipated that these glucagon–nanogel conjugates will be useful as a stabilizing glucagon formulation, allowing for cargo release under mild reducing conditions. [ABSTRACT FROM AUTHOR]

Abstract: Multicolor tunable and multistate switchable organogel is reported, which consists of a cyanostilbene organogelator showing aggregation‐induced enhanced emission and a turn‐on type photochromic diarylethene dye. The mixed organogel can be reversibly switched among four different states (blue‐emitting gel, nonemissive sol, green‐emitting gel, and green‐emitting sol) modulated by a combination of orthogonal stimuli of heat and light. It is interestingly noted that this four‐state switching constitutes a combinational logic circuit consisting of two stimuli inputs and three outputs. Reversible fluorescence writing, switching, erasing, and image patterning processes on this mixture gel system are demonstrated. [ABSTRACT FROM AUTHOR]

Two regioisomeric D1-A-D-A-D1 type π-conjugated molecules (1,4-bis{5-[4-(5-fluoro-7-(5-hexylthiophen-2-yl)benzo[ c][1,2,5]thiadiazole)]­thiophen-2-yl}-2,5-bis(hexyldecyloxy)benzene (Prox-FBT) and 1,4-bis{5-[4-(6-fluoro-7-(5-hexylthiophen-2-yl)benzo[ c][1,2,5]thiadiazole)]­thiophen-2-yl}-2,5-bis(hexyldecyloxy)benzene (Dis-FBT)) are synthesized, by controlling the fluorine topology to be proximal or distal relative to the central core. The different F geometries are confirmed by the 1H-1H nuclear Overhauer effect spectroscopy (NOESY). Clearly different optical, electrochemical, and thermal transition behaviors are obtained, i.e., stronger absorption, deeper valance band (by ≈0.2 eV), and higher melting/recrystallization temperatures (by 7-20 °C) are observed for Dis-FBT. The different intermolecular packing and unit cell structures are also calculated for the two regioisomers, based on the powder X-ray diffraction and 2D grazing-incidence wide-angle X-ray diffraction measurements. A tighter π-π packing with a preferential monoclinic face-on orientation is extracted for Dis-FBT, compared to Prox-FBT with bimodal orientations. Different topological structures significantly affect the electrical and photovoltaic properties, where Prox-FBT shows higher parallel hole mobility (2.3 × 10−3 cm2 V−1 s−1), but Dis-FBT demonstrates higher power conversion efficiency (5.47%) with a larger open-circuit voltage of 0.95 V (vs 0.79 V for Prox-FBT). The findings suggest that small changes in the topological geometry can affect the electronic structure as well as self-assembly behaviors, which can possibly be utilized for fine-adjusting the electrical properties and further optimization of optoelectronic devices. [ABSTRACT FROM AUTHOR]

Biotissue-Inspired Anisotropic Carbon Fiber Composite Hydrogels for Logic Gates, Integrated Soft Actuators, and Sensors with Ultra-High Sensitivity (Adv. Funct. Anisotropic hydrogels, carbon fibers, logic gates, sensors, thermo-responsive actuators Keywords: anisotropic hydrogels; carbon fibers; logic gates; sensors; thermo-responsive actuators EN anisotropic hydrogels carbon fibers logic gates sensors thermo-responsive actuators 1 1 1 03/15/23 20230309 NES 230309 B Thermo-Responsive Actuators b In article 2211189, Jun Fu and co-workers study carbon fiber composited hydrogels that show extremely high anisotropy in mechanical properties, conductivity, and sensitivity. [Extracted from the article]

New technologies that do not rely on antibiotics are urgently needed to treat bacterial infections caused by multidrug-resistant bacteria. Herein, the feasibility of using alternating magnetic field (AMF) to selectively kill enterotoxigenic Escherichia coli strain K99 ( EC K99) in the presence of multianchored glycoconjugate-functionalized magnetic nanoparticles is explored. Poly(ethylene oxide)-poly(acrylic acid)-dopamine functionalized magnetic nanoparticles (PEO-MNPs) are synthesized and functionalized with bacteria-specific glycoconjugate Neu5Ac(α2-3)-Gal-(β1-4)Glcβ-sp (GM3-MNPs) for specific adherence to EC K99. When such mixtures are exposed to an alternate magnetic field (31 kA m−1, 207 KHz), an ≈3-log reduction in colony forming units of EC K99 is achieved in 120 min. Moreover, in a mixed-bacterial culture environment, targeted killing of EC K99 is achieved with minimal damage to nontargeted bacterium. Electron microscopy images along with live/dead staining assays demonstrate visible membrane damage of EC K99 cells in the presence of GM3-MNPs and AMF. Additionally, intracellular adenosine triphosphate (ATP) levels of EC K99 are significantly diminished in the presence of GM3-MNPs and AMF. These results suggest that specific glycoconjugate-functionalized magnetic nanoparticles when mediated by AMF can be potentially used as a novel nonantibiotic treatment platform to inactivate/kill targeted bacterial pathogens, with minimal impact on normal microflora and the affected body region/tissue. [ABSTRACT FROM AUTHOR]

In order to realize the promising potential of MoS2 as the alternative channel material, it is essential to achieve high-performance top-gated MoS2 field-effect transistors (FETs), especially since the back-gated counterparts cannot control the device individually. Although uniform high- k dielectric films, such as HfO2, can be obtained through the introduction of artificial nucleation sites on the MoS2 channel to fabricate top-gated FETs, this would inevitably degrade their channel/dielectric interface quality, induce significant charged impurity scattering and lower carrier mobility. In this work, MoS2 FETs are fabricated using a self-aligned nanowire top-gate, which can effectively reduce the charged impurity scattering on the surface of MoS2. Specifically, the fabricated short-channel devices exhibit impressive electrical performances, such as the high on/off current ratio, low interface trap density, and near-ideal subthreshold slope at room temperature. In addition, the short channel effect is systematically analyzed, which indicates that the phonon scattering can be the dominant scattering mechanism in the devices when the amount of charged impurities is effectively reduced with the self-aligned nanowire gate. All these provide an enhanced fabrication scheme to attain top-gated short-channel devices with the optimized interface and potentially to explore their corresponding performance limits. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF)-type compounds have great potential as emitter molecules in organic light-emitting diodes, allowing for electrofluorescence with 100% internal quantum efficiency. In small molecules, TADF is achieved through the formation of intramolecular charge-transfer states. The only design limitation is the requirement that donor and acceptor entities spatially decouple the highest occupied and lowest unoccupied molecular orbitals, respectively, to minimize exchange splitting. The development of polymeric TADF emitters, on the contrary, has seen comparably small progress and those are typically built up from monomeric units that show promising TADF properties in small molecule studies beforehand. By contrast, herein, a way to achieve TADF properties in cyclic oligomers and polymers composed of non-TADF building blocks is shown. Due to a strongly decreased energy splitting of the polymer with respect to the individual repeating unit between the lowest singlet and triplet excited state (Δ EST) and a sufficiently high radiative decay rate kSr, a highly efficient TADF polymer with up to 71% photoluminescence quantum yield is obtained. For the first time, an encouraging method is provided for producing highly efficient TADF oligomers and polymers from solely non-TADF units via induced conjugation, opening a new design strategy exclusive for polymers. [ABSTRACT FROM AUTHOR]

Surface deposition is a critical step in the application of fragrance-containing products. This contribution presents a novel strategy to enhance the deposition of polymer-based fragrance delivery systems onto cotton substrates from the application medium using phage display identified peptides. Following the identification of cotton binding peptide ligands under fabric softening conditions via phage display, the strongest binding peptide ligand is incorporated into two model polymer-based fragrance delivery systems, viz., polymer profragrances and polymer nanoparticles. The model polymer profragrance used is a linear, water soluble poly( N-(2-hydroxypropyl)methacrylamide) conjugate, while poly(styrene- co-acrylic acid) (PS- co-PAA) nanoparticles prepared via miniemulsion polymerization are chosen as the second model system. The incorporation of the cotton binding peptide ligand into these fragrance delivery systems enhances their surface deposition two- to three-fold, as evidenced by fluorescence intensity measurements. In the case of the fragrance-containing PS- co-PAA nanoparticles, the enhanced surface deposition also translates into an increased fragrance release from the cotton surface according to dynamic headspace sampling measurements. [ABSTRACT FROM AUTHOR]

A prototypical hybrid system formed by strong coupled gold hole arrays and J-aggregate molecules is investigated by using both steady-state spectroscopic method and ultrafast pump-probe approach. In particular, the plasmonic response of the device has been tuned by modifying its periodicity thus to achieve the strongest possible coupling regime. It is found that in the transient absorption spectra, under upper band excitation, the bleaching signal from uncoupled J-aggregate molecules completely disappears. Instead, two distinctive period dependent bleaching bands are formed, clearly fingerprint of the hybrid exciton-plasmon state. The dynamics of these bands is also directly analyzed. A remarkable long lifetime is found especially for the upper band, corresponding to the presence of a trap state in its transient absorption spectra under resonance excitation. Such unique feature should provide a new approach to control quantum-mechanical states under coherent coupling. [ABSTRACT FROM AUTHOR]

Understanding the Solution-State Doping of Donor-Acceptor Polymers Through Tailored Side Chain Engineering for Thermoelectrics (Adv. Funct. Keywords: aggregations; donor-acceptor polymers; organic thermoelectrics; side chain engineering; solution-state dopants EN aggregations donor-acceptor polymers organic thermoelectrics side chain engineering solution-state dopants 1 1 1 12/20/22 20221215 NES 221215 B Donor-Acceptor Polymers b In article number 2207886, Jaeyoung Jang, Hwan Jung, Yong Jin Jeong, and co-workers demonstrate the aggregation effects of donor-acceptor polymers during solution-state doping with 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquino dimethane (F4TCNQ) for organic thermoelectrics. Aggregations, donor-acceptor polymers, organic thermoelectrics, side chain engineering, solution-state dopants. [Extracted from the article]

The design and synthesis of the first organic dyes enabling spontaneous formation of stable J-aggregates in common organic solvents without additives is described. The new dyes are O-BODIPYs with a B-spiranic 4,4-diacyloxyl substitution pattern. Key to the effectiveness of the J-aggregation process is the high conformational rigidity of the B-spiranic molecular design as well as the orthogonal disposition of the B-diacyloxyl substituent and the meso-aryl group with respect to the mean plane of the boradiazaindacene. Atomistic simulations, both in vacuum and in a solvent cage, support the dynamics of the J-aggregation process as well as its dependence on the alkylation pattern of the BODIPY chromophore. A detailed analysis of the photophysical and laser properties of the new dyes provides convincing evidence for the unambiguous assignment of these J-aggregates and their dependence on the environmental conditions. [ABSTRACT FROM AUTHOR]

Vaccines are commonly administered by injection using needles. Although transdermal microneedles are less invasive promising alternatives, needle-free topical vaccination without involving physical damage to the natural skin barrier is still sought after as it can further reduce needle-induced anxiety and is simple to administer. However, this long-standing goal has been elusive since the intact skin is impermeable to most macromolecules. Here, we show an efficient, noninvasive transdermal vaccination by employing two key innovations: the use of hyaluronan (HA) as vaccine carriers and non-ablative laser adjuvants. Conjugates of a model vaccine ovalbumin (OVA) and HA-HA-OVA conjugates-induced more effective maturation of dendritic cells in vitro, compared to OVA. Following topical administration in the skin, HA-OVA conjugates penetrated into the epidermis and dermis in murine and porcine skins, as revealed by intravital microscopy and fluorescence assay. Topical administration of HA-OVA conjugates significantly elevated both humoral and mucosal antibodies, with peak levels at four weeks. An OVA challenge at week eight elicited strong immune-recall responses. With pretreatment of the skin using non-ablative fractional laser beams as adjuvant, strong immunization was achieved with much reduced doses of HA-OVA (1 mg kg-1 OVA). Our results demonstrate the potential of the noninvasive patch-type transdermal vaccination platform. [ABSTRACT FROM AUTHOR]

The thermal gradients generated at submicrometer scale by the millions of transistors contained in integrated circuits are becoming the key limiting factor for device integration in micro- and nanoelectronics. Noncontact thermometric techniques with high-spatial resolution are, thus, essential for noninvasive off-chip characterization and heat management on Si surfaces. Here, the first ratiometric luminescent molecular thermometer implemented in a self-assembled polymer monolayer functionalized Si surface is reported. The functionalization of Si surfaces with luminescent thermometers constitutes a proof-of-concept that foretells a wide range of applications in Si-based micro- and nanostructures. The thermometric functionalization of the Si surface with Tb3+ and Eu3+ complexes leads to a thermal sensitivity up to 1.43% K−1, a cycle-recycle reliability of 98.6%, and a temperature uncertainty of less than 0.3 K. The functionalized surface presents reversible bistability that can be used as an optically active molecular demultiplexer. [ABSTRACT FROM AUTHOR]

Peptide materials based on the aggregation of polyphenylalanine conjugates containing gadolinium complexes and acting as potential contrast agents (CAs) in magnetic resonance imaging (MRI) are described. Monomers contain two (F2) or four (F4) phenylalanine residues for self-assembly, a chelating agent, 1,4,7,10-tetraazacyclododecane-N,N,N,N-tetraacetic acid (DOTA) or diethylenetriaminepentaacetic acid (DTPA), for achieving gadolinium coordination, and ethoxylic linkers at two (L2) or six (L6) poly(ethylene glycol) (PEG) units between the chelating group and the peptide region. Both DOTA and DTPA tetraphenylalanine derivatives, and their gadolinium complexes DOTA(Gd)-L6-F4 and DTPA(Gd)-L6-F4, are able to self-aggregate at very low concentration. Structural characterization, obtained by circular dichroism and infrared measurements, confirms the amyloid type fibril formation in which an antiparallel peptide alignment is preferred. Amyloid type fibril formation is also observed, in solid state, by transmission electron microscopy images and X-ray diffraction patterns. The relaxivity values of DOTA(Gd)-L6-F4 and DTPA(Gd)-L6-F4 and their ability to enhance the MRI cellular response on the J774A.1 mouse macrophages cell line indicate that these peptide materials are promising candidate as a new class of supramolecular gadolinium based MRI contrast agents. [ABSTRACT FROM AUTHOR]

A family of trigonal starburst conjugated molecules (TrFPy, TrFPy, and TrF2Py) composed of a truxene core and pyrene cappers with various bridge lengths is synthesized and characterized. The incorporation of pyrene cappers successfully depress the crystallization tendency, resulting in enhanced glassy temperature and improved morphological stability of the thin films. The high photoluminescence yield in neat films and excellent thermal stability render these pyrene-capped starbursts promising lasing optical gain media. Low amplified spontaneous emission (ASE) thresholds ( EthASE) of 180 nJ pulse-1 and 101 nJ pulse-1 were recorded for TrFPy and TrF2Py, respectively. One dimensional distributed feedback (1D DFB) lasers demonstrated lasing threshold of 9.3 kW/cm2 and 7.3 kW/cm2 for TrFPy (at 457 nm) and TrF2Py lasers (at 451 nm), respectively. The ASE performance of TrFPy and TrF2Py in an ambient condition was recorded with various annealing temperature (from 80 to 250 °C, 10 min). Surprisingly, TrFPy exhibited excellent ASE stability in an ambient condition, which is still detectable even after annealing at 250 °C for 10 min. The results suggest the pyrene-capped molecular design strategy is positive on improving the optical gain stability and meanwhile maintaining excellent lasing properties. [ABSTRACT FROM AUTHOR]

A straightforward end-capping strategy is applied to synthesize xanthate-functional poly(2-alkyl-2-oxazoline)s (PAOx) that enable gold nanoparticle functionalization by a direct 'grafting to' approach with citrate-stabilized gold nanoparticles (AuNPs). Owing to the presence of remaining citrate groups, the obtained PAOx@AuNPs exhibit dual stabilization by repulsive electrostatic and steric interactions giving access to water soluble molecular AND logic gates, wherein environmental temperature and ionic strength constitute the input signals, and the solution color the output signal. The temperature input value could be tuned by variation of the PAOx polymer composition, from 22 °C for poly(2- npropyl-2-oxazoline)@AuNPs to 85 °C for poly(2-ethyl-2-oxazoline)@AuNPs. Besides, advancing the fascinating field of molecular logic gates, the present research offers a facile strategy for the synthesis of PAOx@AuNPs of interest in fields spanning nanotechnology and biomedical sciences. In addition, the functionalization of PAOx with xanthate offers straightforward access to thiol-functional PAOx of high interest in polymer science. [ABSTRACT FROM AUTHOR]

A new category of iron oxide nanoparticles (surface active maghemite nanoparticles (SAMNs, γ-Fe2O3)) allows the intimate chemical and electrical contact with DNA by direct covalent binding. On these basis, different DNA-nanoparticle architectures are developed and used as platform for studying electrical properties of DNA. The macroscopic 3D nanobioconjugate, constituted of 5% SAMNs, 70% water, and 25% DNA, shows high stability, electrochemical reversibility and, moreover, electrical conductivity (70-80 Ω cm−1). Reversible electron transfer at the interface between nanoparticles and DNA is unequivocally demonstrated by Mössbauer spectroscopy, which shows the appearance of Fe(II) atoms on nanoparticles following nanobioconjugate formation. This represents the first example of permanent electron exchange by DNA, as well as, of DNA conductivity at a macroscopic scale. Finally, the most probable configuration of the binding is tentatively modeled by density functional theory (DFT/UBP86/6-31+G*), showing the occurrence of electron transfer from the organic orbitals of DNA to surface exposed Fe(III) on nanoparticles, as well as the generation of defects (holes) on the DNA bases. The unequivocal demonstration of DNA conduction provides a new perspective in the five decades long debate about electrical properties of this biopolymer, further suggesting novel approaches for DNA exploitation in nanoelectronics. [ABSTRACT FROM AUTHOR]