氨基酸与钠离子非共价键相互作用的电喷雾质谱研究

实验研究中常常观察到钠离子与一些多肽或蛋白质有较强的非共价键结合能力,这种非共价键相互作用可能与生物的一些功能和活性有关.为了进一步了解这一结合作用,我们应用电喷雾质谱研究了常见的20种氨基酸与钠离子在溶液中的非共价键相互作用.实验研究中发现脯氨酸和苯丙胺酸与钠离子有较强的非共价键结合能力.……

Fabrication of microcapsule arrays on chemically patterned surfaces via covalent linking

A method for fabricating arrays of microcapsules covalently immobilized onto chemically patterned substrates was developed.The core-shell microparticles with poly(allylamine hydrochloride)(PAH) as the outermost layer were obtained by layer-by-layer (LbL) assembly,which were further treated with glutaraldehyde to endow the particles with abundant aldehyde groups on their surfaces.The particles were then covalently coupled to the chemically patterned regions with amino groups created by microcontact printing (μCP).After dissolution of the core particles,arrays of the hollow microcapsules with unchanged structures were obtained.These arrays could stand rigorous environmental conditions of higher ionic strength,and lower and higher pH values.Thus,the technique could be possibly applied to exploiting chips of microcontainers or microreactors in sensing technology.

Recent advances in polysaccharide-based hydrogels for synthesis and applications

Hydrogels are three-dimensional(3D)crosslinked hydrophilic polymer networks that have garnered tremendous interests in many fields,including water treatment,energy storage,and regenerative medicine.However,conventional synthetic polymer hydrogels have poor biocompatibility.In this context,polysaccharides,a class of renewable natural materials with biocompatible and biodegradable properties,have been utilized as building blocks to yield polysaccharide-based hydrogels through physical and/or chemical crosslinking of polysaccharides via a variety of monomers or ions.These polysaccharide-derived hydrogels exhibit peculiar physicochemical properties and excellent mechanical properties due to their unique structures and abundant functional groups.This review focuses on recent advances in synthesis and applications of polysaccharide-based hydrogels by capitalizing on a set of biocompatible and biodegradable polysaccharides(i.e.,cellulose,alginate,chitosan,and cyclodextrins[CDs]).First,we introduce the design and synthesis principles for crafting polysaccharide-based hydrogels.Second,polysaccharidebased hydrogels that are interconnected via various crosslinking strategies(e.g.,physical crosslinking,chemical crosslinking,and double networking)are summarized.In particular,the introduction of noncovalent and/or dynamic covalent interactions imparts polysaccharide-based hydrogels with a myriad of intriguing performances(e.g.,stimuli–response and self-recovery).Third,the diverse applications of polysaccharide-based hydrogels in self-healing,sensory,supercapacitor,battery,drug delivery,wound healing,tissues engineering,and bioimaging fields are discussed.Finally,the perspectives of polysaccharide-based hydrogels that promote their future design to enable new functions and applications are outlined.

Bioinspired Hydrogels with Muscle-Like Structure for AIEgen-Guided Selective Self-Healing

Living systems,including human beings,animals,and plants,display the power to self-heal spontaneously after being damaged.The self-healing is usually selective,which means that the healing efficiency is related to the spatial distribution of dynamic interfacial interactions of the two rupturing surfaces.Current artificial systems use noncovalent interactions or dynamic covalent bonds to prepare self-healing materials.However,they can only show nonselective self-healing due to their homogeneous internal structures.Herein,we report the construction of a composite hydrogel Gel-C consisting of three different self-healing hydrogels(Gel-Y,Gel-G,and Gel-O)through the use of classic bilayer hydrogel technology.When the composite hydrogel was cut into two pieces,the relative orientation of the parts was rotated through different angles to study the differences in self-healing.Owing to the heterogeneous internal structure of the composite hydrogel and the recognition specificity of each included hydrogel,the interfacial dynamic interactions distribution of the two rupturing surfaces is diverse.The results of tensile tests demonstrated that these rotated samples exhibited different self-healing efficiencies.This system realized the transformation of artificial materials from nonselective self-healing to selective selfhealing,providing inspiration for the development of novel biological materials and engineering materials.

High-loading and thermally stable Pt1/MgAl1.2Fe0.8O4 single-atom catalysts for high-temperature applications

Single-atom catalysts(SACs)have attracted extensive attention in the field of heterogeneous catalysis.However,the fabrication of SACs with high loading and hightemperature stability remains a grand challenge,especially on oxide supports.In this work,we have demonstrated that through strong covalent metal-support interaction,highloading and thermally stable single-atom Pt catalysts can be readily prepared by using Fe modified spinel as support.Better catalytic performance in N2O decomposition reaction is obtained on such SACs than their nanocatalyst counterpart and low-surface-area Fe2O3 supported Pt SACs.This work provides a strategy for the fabrication of high-loading and thermally stable SACs for applications at high temperatures.

Boron-based Drug Design for Cancer Therapy

1 Results Selective inhibition of protein tyrosine kinases is gaining importance as an effective therapeutic approach for the treatment of a wide range of human cancers.The epidermal growth factor receptor (EGFR) protein tyrosine kinase is one of the important kinases that play a fundamental role in cell growth signal pathways.We focused on the 4-anilinoquinazoline framework,which is observed in both compounds as a common structure.A boron atom has a vacant orbital and interconverts with ease between th...