Latest ArticlesIn 2022, The MOE Key Laboratory of Macromolecular Synthesis and Functionalization in Zhejiang University had achieved several important results. First, a series of well-defined dinuclear organoboron catalysts were developed to precisely control the enchainment of ether and carbonate segments during the copolymerization of CO2 and epoxides. Second, polyester had been synthesized through cationic copolymerization of cyclic anhydride. Third, ring-opening polymerization of carbon dioxide based valerolactone had been achieved, revealing the prospect of 3-ethylidene-6-vinyltetrahydro-2H-pyran-2-one (EVL) in utilizing CO2 and synthesizing functional polymers. Fourth, machine learning methods have been applied to biomaterial research, enabling high-throughput screening of functional biomaterial surfaces for implantable devices, and searching for potent antimicrobial peptides in whole combinatorial peptide libraries. Fifth, methods of characterization of biomacromolecule RNA transcription and manipulation of nucleoside modification were developed. Sixth, artificial enzymes-armed Bifidobacterium Longum probiotics were established to tune down gut inflammation. Seventh, three-dimensional (3D) printing technologies were used to engineer tough supramolecular hydrogels. Eighth, hydroplastic foaming graphene frameworks for acoustic and conductive polymer composites were provided for application. Ninth, aggregate photophysics about the nature of through-space interactions (TSIs) and manipulating their strength in small molecules with non-conjugated structure had been elucidated. Tenth, the forming mechanism of a newfound nested texture in poly(l-lactic acid) (PLLA) spherulitic films had been revealed. Finally, the isotropically dyeing mechanism of KDP single crystals grown from hydrogels have been explored. The related works are reviewed in this paper.
Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and electrophiles. However, the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic deprotonation. In this study, we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic CH bonds to cyclic N-sulfonyl ketamines through π-coordination. This strategy enables the synthesis of a diverse range of N-sulfonyl amines, and subsequent diversification of the addition products showcases the synthetic potential of this protocol.
Organic electrochemical transistors (OECTs) have emerged as one type of promising building block for neuromorphic systems owing to their capability of mimicking the morphology and functions of biological neurons and synapses. Currently, numerous kinds of OECTs have been developed, while self-healing performance has been neglected in most reported OECTs. In this work, the OECTs using self-healing polymer electrolytes as dielectric layers are proposed. Several important synaptic behaviors are simulated in the OECTs by doping the channel layers with ions from the electrolytes. Benefitting from the dynamic hydrogen bonds in the self-healing polymer electrolytes, the OECTs can successfully maintain their electrical performance and the ability of emulating synaptic behaviors after self-healing compared with the initial state. More significantly, the sublinear spatial summation function is demonstrated in the OECTs and their potential in flexible electronics is also validated. These results suggest that our devices are expected to be a vital component in the development of future wearable and bioimplantable neuromorphic systems.
Vanadium flow batteries (VFBs) have drawn considerable attention as an emerging technology for large-scale energy storage systems (ESSs). One of the pivotal challenges is the availability of eligible ion exchange membranes (ICMs) that provide high ion selectivity, proton conductivity, and stability under rigorous condition. Herein, a 'side-chain-type' strategy has been employed to fabricate highly stable phenolphthalein-based cardo poly(arylene ether ketone)s (PAEKs) membrane with low area resistance (0.058 Ω cm2), in which flexible alkyl spacers effectively alleviated inductive withdrawing effect from terminal ion exchange groups thus enabling a stable backbone. The assembled VFBs based on PAEKs bearing pendent alkyl chain terminated with quaternary ammonium (Q-PPhEK) demonstrated an energy efficiency above 80% over 700 cycles at 160 mA/cm2. Such a remarkable results revealed that the side-chain-type strategy contributed to enhancing the ICMs stability in strong oxidizing environment, meanwhile, more interesting backbones would be woken with this design engaging in stable ICMs for VFBs.
Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) plays an indispensable role in analyzing protein covalent structures. The reliable identification of amino acid residues and modifications relies on the mass accuracy, which is highly dependent on calibration. However, the accuracy provided by the currently available calibrants still needs further improvement in terms of compatibility with multiple tandem MS modes or ion polarity modes, calibratable range, and minimizing suppression of and interference with analyte signals. Here aiming at developing a versatile calibrant to solve these problem, we designed a synthetic peptide format of calibrant R(GDP) (referred to as "Gly-Asp-Pro, GDP") according to the chemical natures of amino acids and polypeptide fragmentation rules in tandem MS. With four types of amino acid residues selected and arranged through rational designs, a GDP peptide produces highly regulated fragments that give rise to evenly spaced signals in each tandem MS mode and is compatible with both positive and negative ion modes. In internal calibration, its regulated fragmentation pattern minimizes interference with analyte signals, and using a single peptide as the input minimizes suppression of the analyte signals. As demonstrated by analyses of proteins including monoclonal antibody and Aβ-42, these features allowed significant increase of the mass accuracy and precision, which improved sequence coverage and sequence resolution in sequence analyses (including de novo sequencing). This rational design strategy may also inspire further development of synthetic calibrants that benefit structural analysis of biomolecules.
Promethazine (PHZ) is used as a sedative in veterinary medicine, and its residue can threaten the health of human. The electrochemical detection of PHZ is suitable method for application in the field. However, the traditional electroanalysis is difficult to perform directly in meat samples due to matrix interference. This work integrates magnetic solid-phase extraction and differential pulse voltammetry for highly sensitive and selective determination of PHZ in beef and beef liver for the first time. CoFe2O4/graphene coated with C18-functionalized mesoporous silica (MG@mSiO2-C18) is synthesized as dispersed magnetic adsorbent to extract PHZ. Magnetic glassy carbon electrode modified with nitrogen-doped hollow carbon microspheres (HCM) attracts the MG@mSiO2-C18 with PHZ, and directly detects the PHZ without elution procedure. MG@mSiO2-C18 can separate PHZ to avoid the interference of impurities on following detection, and also concentrate PHZ on magnetic electrode. Additionally, the electrode modification with HCM can amplify the electrochemical signal of PHZ. Finally, the integrated PHZ determination method exhibits a wide linear range from 0.08 µmol/L to 300 µmol/L with a low limit of detection of 9.8 nmol/L. The beef sample analysis presents excellent recovery, demonstrating that this protocol is promising for the rapid and onsite detection of PHZ in real meat samples
The design and syntheses of metal-organic cages (MOCs) based on polyoxometalates (POMs) building blocks have attracted increasing attention due to their intriguing molecular architectures and physicochemical properties. In this work, we have successfully synthesized and systematically characterized a tetrahedral polyoxometalate-based organic cage (POC), K3Na17H12[(C4H6O6)6[Ni4(OH)3(A-α-SiW9O34)]4]·96H2O (Ni16L6(SiW9)4), using tritopic Ni4-substituted Keggin cluster (Ni4SiW9) as nodes and flexible L-(+)-tartaric acid ligands as linkers. The resulting POC tetrahedron has been firstly investigated as efficient catalyst for visible-light-driven hydrogen production, achieving a turnover number of 15,500 after 96-h photocatalysis. Such high catalytic performance of Ni16L6(SiW9)4 POC catalyst could be attributed to its unique cage structure, thereby offering more efficient catalytic component accessibility. In addition, spectroscopic analyses illustrated the photocatalytic mechanism and the structural stability of the TBA-Ni16L6(SiW9)4 catalyst during the photocatalytic process.
Accurate detection of uric acid (UA) is crucial for diagnosing gout, yet traditional sweat-based UA sensors continue to face challenges posed by complex and costly electrode fabrication methods, as well as weakly hydrophilic substrates. Here, we designed and developed simple, low-cost, and hydrophilic sweat UA detection sensors constructed by carbon electrodes and cellulose paper substrates. The carbon electrodes were made by carbonized polyimide films through a simple, one-step laser engraving method. Our electrodes are porous, possess a large specific surface area, and are flexible and conductive. The substrates were composed of highly hydrophilic cellulose paper that can effectively collect, store, and transport sweat. The constructed electrodes demonstrate high sensitivity of 0.4 µA L µmol−1 cm−2, wide linear range of 2–100 µmol/L. In addition, our electrodes demonstrate high selectivity, excellent reproducibility, high flexibility, and outstanding stability against mechanical bending, temperature variations, and extended storage periods. Furthermore, our sensors have been proven to provide reliable results when detecting UA levels in real sweat and on real human skin. We envision that these sensors hold enormous potential for use in the prognosis, diagnosis, and treatment of gout.
Artificial Z(S)-scheme photocatalytic water splitting systems have attracted extensive attention due to their advantages such as wide light absorption range, high charge separation efficiency and strong carrier redox ability. However, it is still challenging to design and prepare Z(S)-scheme photocatalysts with low-cost and highly stability for efficiently photocatalytic overall water splitting using solar energy. This review mainly introduces various strategies to improve the photocatalytic water splitting performance of Z(S)-scheme systems. These strategies mainly focus on enhancing or extending the range of light absorption, promoting charge separation, and enhancing surface redox reaction in Z(S)-scheme systems. Finally, the main challenges of Z(S)-scheme photocatalytic water splitting systems and their future development directions are pointed out. This review would be beneficial to understanding the challenges and opportunities faced by the research field of Z(S)-scheme photocatalytic systems, and has important guiding significance for the development and utilization of high-performance Z(S)-scheme photocatalytic reaction system in the future.