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Cortisol is a vital glucocorticoid hormone reflecting stress levels and related disease processes. In this study, we report an aptamer-functionalized plasmonic nano-urchin (α-FeOOH@Au-aptamer)-aided cortisol-capturing and surface-enhanced Raman spectroscopy (SERS) analysis approach. The designed α-FeOOH@Au-aptamer exhibits a well-patterned plasma structure, which combines the good SERS enhancement ability of reduced nanogaps between the Au plasma and the hot spot–favored structure of anisotropic tips from α-FeOOH urchins, with the high affinity of the aptamer towards cortisol molecules. The α-FeOOH@Au-aptamer achieved reporter-free SERS quantification for cortisol with good sensitivity (limit of detection <0.28 μmol L−1), robust salt (1.0 mol per L NaCl) and protein (5.0 mg per mL bovine serum protein) tolerance, favorable reproducibility, as well as good reusability. We further demonstrated the good cortisol-capturing ability and SERS efficacy of the α-FeOOH@Au-aptamer profiling in the serum and urine samples. Our approach provides an alternative tool for cortisol analysis and a reference strategy for report-free SERS detection of small molecules.

Deep neural network (DNN) applications are typically represented by tensor programs. To boost the performance of DNN computations, existing works adopt fully equivalent transformations for tensor program optimization by guaranteeing the equivalence on each element of tensors. However, as there are thousands of elements in a tensor, such optimization misses the opportunities that allow the in-equivalence of minority elements. In this work, we propose Pet, the first work that introduces partially equivalent transformations to optimize tensor programs. To maintain the functional equivalence of tensor programs, Pet automatically finds and corrects the in-equivalent positions by leveraging the multi-linearity of DNN computations. Pet further uses a mutation manager to improve search efficiency. Evaluation results show that Pet can achieve up to 1.98$\times$× and 2.20$\times$× speedups on NVIDIA Tesla A100 and V100 respectively compared with existing DNN frameworks by introducing new optimization opportunities of partially equivalent transformations.

Cancer vaccines, which directly pulsed in vivodendritic cells (DCs) with specific antigens and immunostimulatory adjuvants, showed great potential for cancer immunoprevention. However, most of them were limited by suboptimal outcomes, mainly owing to overlooking the complex biology of DC phenotypes. Herein, based on adjuvant-induced antigen assembly, we developed aptamer-functionalized nanovaccines for in vivoDC subset-targeted codelivery of tumor-related antigens and immunostimulatory adjuvants. We chose two aptamers, iDC and CD209, and tested their performance on DC targeting. Our results verified that these aptamer-functionalized nanovaccines could specifically recognize circulating classical DCs (cDCs), a subset of DCs capable of priming naïve T cells, noting that iDC outperformed CD209 in this regard. With excellent cDC-targeting capability, the iDC-functionalized nanovaccine induced potent antitumor immunity, leading to effective inhibition of tumor occurrence and metastasis, thus providing a promising platform for cancer immunoprevention.

As intelligent probes, dynamic and controllable molecular switches are useful tools for probing and intervening in life processes. However, the types and properties of molecular switches are still relatively single and often can only make two actions: “off” and “on”. Therefore, the development of novel molecular switches with multiple colors and multiple instructions is very challenging. Herein, we propose a novel strategy based on the instability of the Lewis acid–base pair (boron (B) and nitrogen (N)), such as introducing the Schiff base (C═N) group into the aminoborane skeleton and preparing the novel molecular switches BN-HDZand BN-HDZ-N. These two molecules were found to have good multicolor fluorescence switching capability for methanol. Surprisingly, the compound BN-HDZ-Nshows unprecedented visual identification for the butanol isomers and could be made into a portable strip for simple and rapid visual identification of the four isomers of butanol, promising an alternative to conventional Lucas reagents. This provides a novel strategy for the design and fabrication of novel multicolor-tunable molecular switches with visual identification of isomers.

Chemically synthetic receptors that establish cells a new sense-and-respond capability to interact with outer worlds are highly desired, but rarely reported. In this work, we develop a membrane-anchored synthetic receptor (Ts-pHLIP-Pr) using DNA and peptide as the building block to equip cells with artificial signaling pathways. Upon sensing external pH stimuli, the Pr module can be translocated across the cell membrane via the conformation switch of pHLIP, enabling membrane-proximal recruitment of specific proteins to trigger downstream signaling cascades. Our experimental results demonstrate the capability of Ts-pHLIP-Pr for regulating PKCε-related signaling events upon responding to external pH reduction. With a modular feature, this receptor can be extended to elicit T cell activation through low-pH environment-induced directional movement of cytoplasmic ZAP70. Our work is expected to offer a new paradigm for intelligent synthetic biology and customized cell engineering.

A series of silver coordination complexes (CCs) have been synthesized through self-assembly of five pyridine-substituted tetraphenylethylene stereoisomer ligands with silver ions (named Ag-TPE-2by-1-E, Ag-TPE-2by-2-E, Ag-TPE-2by-2-Z, Ag-TPE-2by-3-E, and Ag-TPE-2by-3-Z). These silver CCs show distinct topologies including beaded chain frameworks, linear structures, and discrete metallacycles. The single-crystal analysis results reveal the critical role of the space distribution of the coordination site and stereoisomer ligands in controlling the silver CCs’ geometry configuration and modulating the optical properties. Luminescent investigations revealed that Ag-TPE-2by-2-E, Ag-TPE-2by-2-Z, Ag-TPE-2by-3-E, and Ag-TPE-2by-3-Zpossess obvious mechanocharomic behaviors, which can be achieved several reversible cycles through repeated grinding and methanol soaking processes. However, the Ag-TPE-2by-1-Eshowed tenacious stability toward mechanical grinding and temperature. Thus, these silver CCs provide a good platform to investigate the influence of the space distribution of the coordination site of ligands on their geometry and mechanocharomic properties.

The inner region of solid tumors is found to be high-pressure, hypoxic, and immunosuppressive, providing a breeding ground for tumor aggressiveness and metastasis. While intratumoral accumulation of nanomedicines combined with immunomodulation would significantly enhance therapeutic efficacy, such potential is challenged by the compressed environment and distinct heterogeneity of the tumor bulk. By using an apoptotic body (AB) as the carrier, we develop an effective and universal intratumoral nanomedicine delivery system for the long-lasting remission of tumors. Our results show that the AB-encapsulated nanomedicine (using CpG immunoadjuvant-modified gold–silver nanorods as a model), after intravenous injection, can be specifically phagocytosed by inflammatory Ly-6C+monocytes, which then actively infiltrate the tumor center via their natural tumor-homing tendency. With the integration of AB-facilitated intratumoral accumulation, the nanorod-based photothermal effect, and CpG-promoted immunostimulation, this cell-mediated delivery system can not only efficiently ablate primary tumors but also elicit a potent immunity to prevent tumors from metastasizing and recurring.

Novel metal–organic frameworks (MOFs) based solid catalysts have been synthesized by encapsulating Hemin into the HKUST-1 MOF materials. These have been first applied in the chemiluminescence field with outstanding performance. The functionalized MOFs not only maintain an excellent catalytic activity inheriting from Hemin but also can be cyclically utilized as solid mimic peroxidases in the neutral condition. The synthesized Hemin@HKUST-1 composites have been used to develop practical sensors for H2O2and glucose with wide response ranges and low detection limits. It was envisioned that catalyst-functionalized MOFs for chemiluminescence sensing would have promising applications in green, selective, and sensitive detection of target analytes in the future.

For years, dissolved oxygen (O2) has been regarded as a quenching species in Ru(bpy)32+electrochemiluminescent (ECL) systems; however, in the present study, O2was found to act as a coreactant for Ru(bpy)32+ECL in Nafion film, resulting in a strong ECL light emission. ECL experiments were carried out at a Ru(bpy)32+/Nafion film-modified glassy carbon electrode (GCE) immersing in air-saturated phosphate buffer solution (pH 7.4). Scanning in the potential range of +1.5 to −1.0 V resulted in three luminescent processes, including two potential-dependent luminescence peaks (ECL-1 and ECL-2), and one potential-independent persistent luminescence emission (CL-P). Therein, ECL-2 occurring at potential less than −0.5 V was demonstrated to be a new chemiluminescent reactions between O2and Ru(bpy)32+. In ECL-2, Nafion film plays important roles in stabilizing Ru(bpy)33+and O2•−radical essentially for producing the new ECL. Unlike previously reported ECL processes, ECL-2 peak potential is dependent on the reduction potential of the coreactant (i.e., O2) rather than the redox potentials of the luminopore, Ru(bpy)32+, which would provide a useful way to probe O2, O2•−radical, and their stabilities in electrochemical reactions.

The establishment of a reliable and sensitive method for the detection of flavonoids, such as kaempferol (Kae) and quercetin (Que), is important and challenging in food chemistry and pharmacology because numerous structural analogues may interfere with the detection. Until now, designing an efficient switch-on fluorescence sensing strategy for Kae and Que was still in the unachievable stage. In this work, a switch-on near-infrared (NIR) luminescence sensing assay for Kae and Que was fabricated based on a metal–organic framework (MOF) called IQBA-Yb for the first time. The fluorescence enhancing mechanism was that analytes served as additional “antenna” of Yb3+, leading to the efficient switch-on NIR emission under excitation at 467 nm. Meanwhile, the combination results of experiment and theoretical calculation revealed that there existed hydrogen bonds between Kae, Que, and the MOF skeleton, further promoting the energy transfer between the analyte and Yb3+and facilitating fluorescence enhancement response. The developed probe possessed excellent sensing capability for Kae and Que, accompanied by a wide linear range (0.04–70, 0.06–90 μM), low detection limit (0.01, 0.06 μM), and short response time (20 min, 6 min), which was used to determine the Kae and Que contents in Green Lake and eatable Que samples with satisfactory results.

The electrochemiluminescence (ECL) behaviors of tris(2,2-bipyridine)ruthenium(II)/triethylamine (Ru(bpy) 32+/TEA) in 1-butyl-3-methylimidazolium hexafluorophosphate (BMIPF 6) ionic liquid were investigated and compared with those in aqueous solution (pH 7.0 PBS) at a gold electrode. It was found that the Ru(bpy) 32+/TEA system gave rise to one small and one large peak ECL peak at anodic process. The small anodic ECL peak observed around +0.90 V is due to the direct electrochemical oxidation of TEA at the gold electrode and further chemiluminescent reaction of its oxidative product with Ru(bpy) 32+. The large anodic ECL peak found around +1.35 V results from the reversible electrochemical oxidation of Ru(bpy) 32+coupled with a slow following reaction of TEA with Ru(bpy) 33+. The effects of viscosity and ionic strength of ionic liquid on diffusion coefficients, catalytic efficiency, and ECL intensity were investigated and discussed to reveal the ECL mechanism of Ru(bpy) 32+/TEA system in the ionic liquid of BMIPF 6.

The development of a facile synthesis and controllable layer stacking approach for covalent organic frameworks (COFs) is an important issue for modulating their properties and realizing their application diversity. Herein, three COF isomers with different stacking models (eclipsed AA, staggered AB, and ABC stacking) were obtained by modulating the reaction temperature and solvent medium. Experimental and theoretical calculations show that the ABC stacking isomer obtained at room temperature is the kinetic product, while the AA stacking isomer prepared by the solvothermal method is a thermodynamic product. Owing to the tautomerism involved in the reaction process, these isomers possess different ratios of enol and keto forms. Thus, they exhibit different generation efficiencies of Type I and Type II reactive oxygen species (ROS). The ABC stacking isomers could be employed as metal-free heterogeneous photocatalysts for visible-light-induced oxidation of amines to imines, owing to the highest generation efficiency of Type I ROS.

Cells sense and respond to the external environment, mainly through proteins presented on the membrane where their expression and conformation are dynamically regulated via intracellular programs. Here, we engineer a cell–surface nanoarchitecture that realizes molecular-recognition-initiated DNA assembly to mimic the dynamic behavior of membrane proteins, enabling the manipulation of cellular interaction in response to environmental changes. Our results show that this membrane-anchored DNA nanoarchitecture can be specifically activated by cell-responsive signals to external stimulation. Accordingly, multiple functional modules can be assembled onto the membrane to equip the cell with cell-type-specific binding and killing. This system is expected to offer a new paradigm for engineering therapeutic cells with customized sensing/response pathways.

An acylation of arenes with aldehydes through dual C–H activations at room temperature is reported. The acylation was initiated by phenanthraquinone-catalyzed hydrogen atom transfer from aldehyde under visible light irradiation. The aldehyde-derived acyl radical merged with palladium-catalyzed activation of arenes to afford the cross coupling products.

Rational design of controllable drug release systems is important for tumor treatments due to the nonspecific toxicity of many chemotherapeutics. Herein, laser or light responsive pharmaceutical delivery nanoparticles are designed, by taking the advantages of redox responsive selenium (Se) substituted polymer as shell and photosensitive porphyrin zirconium metal–organic frameworks (MOF) as core. In detail, redox cleavable di‐(1‐hydroxylundecyl) selenide (DH‐Se), biocompatible poly(ethylene glycol) (PEG), and poly(propylene glycol) (PPG) are randomly polymerized to form poly(DH‐Se/PEG/PPG urethane), which is used to coat the reactive oxygen species' (ROS) producible porous porphyrin zirconium metal organization formulation (PCN‐224 MOF) to form the final poly(DH‐Se/PEG/PPG urethane)@MOF shell–core nanoparticle with spherical shape by emulsion approach. Interestingly, poly(DH‐Se/PEG/PPG urethane)@MOF nanoparticles with loading of chemotherapeutic doxorubicin (DOX) experience a fast and controllable release, which can realize the combination of chemotherapy and photodynamic therapy upon irradiation with laser light, due to the light‐triggered ROS production by MOF which further causes the cleavage of poly(DH‐Se/PEG/PPG urethane) polymer chain and the release of encapsulated DOX. To the best of the authors' knowledge, this is the first design of utilizing MOF and selenium substituted polymer as controllable drug release carriers, which might be beneficial for precise chemotherapy and photodynamic therapy combination. A novel poly(DH‐Se/PEG/PPG urethane)@MOF shell–core nanoparticle, made of selenium‐containing polymer and metal–organic frameworks (MOF), is designed as an intelligent chemotherapeutic doxorubicin (DOX) carrier, with controllable drug release ability thanks to the light triggered reactive oxygen species production by the MOF, which further causes the cleavage of the selenium substituted poly(DH‐Se/PEG/PPG urethane) polymer chain and the release of encapsulated DOX.