Controlled Click‐Assembly of Well‐Defined Hetero‐Bifunctional Cubic Silsesquioxanes and Their Application in Targeted Bioimaging

A general procedure for the assembly of hetero‐bifunctional cubic silsesquioxanes with diverse functionality and a perfectly controlled distribution of functional groups on the inorganic framework has been developed. The method is based on a two‐step sequence of mono‐ and hepta‐functionalization through the ligand‐accelerated copper(I)‐catalyzed azide–alkyne cycloaddition of a readily available octaazido cubic silsesquioxane. The stoichiometry of the reactants and the law of binomial distribution essentially determine the selectivity of the key monofunctionalization reaction when a copper catalyst with strong donor ligands is used. The methodology has been applied to the preparation of a set of bifunctional nano‐building‐blocks with orthogonal reactivity for the controlled assembly of precisely defined hybrid nanomaterials and a fluorescent multivalent probe for application in targeted cell‐imaging. The inorganic cage provides an improved photostability to the covalently attached dye as well as a convenient framework for the 3D multivalent display of the pendant epitopes. Thus, fluorescent bioprobes based on well‐defined cubic silsesquioxanes offer interesting advantages over more conventional fully organic analogues and ill‐defined hybrid nanoparticles and promise to become powerful tools for the study of cell biology and for biomedical applications.     

CMPO-离子液体萃取分离铀(VI)体系的电化学性质

研究了辛基(苯基)-N,N-二异丁基胺甲酰基甲基氧化膦(CMPO)-离子液体(IL)从硝酸铀酰水溶液中萃取铀(VI)的电化学行为, 离子液体(IL)为1-丁基-3-甲基咪唑双三氟甲基磺酰亚胺盐(C₄mimNTf₂). 用等摩尔系列法测得萃取过程中CMPO与U(VI)形成摩尔比为3:1的配合物. 用循环伏安法研究了萃取液中U(VI)-CMPO配合物的电化学性质, 结果表明, 在C₄mimNTf₂中U(VI)-CMPO 配合物经过准可逆还原生成U(V)-CMPO 配合物, U(VI)/U(V)电对的表观氧化还原电势(E^Θ, vs Fc/Fc⁺)为(?0.885±0.008) V. 对萃取液进行控制电位电解, 发现在铂片上有沉淀析出. X射线光电子能谱(XPS) 测试结果表明, 沉积物中只含有U(VI)、U(IV)和氧, 而CMPO和C₄mimNTf₂没有被夹带析出.     

Exact Finite-Dimensional Filter for Exponential Functionals of the State of Beneš Systems

The purpose of this article is to derive finite-dimensional filters for exponential functionals of the state of nonlinear Bene? type filtering systems with correlated noises. These new filters can be applied in the state reconstruction of doubly–stochastic auto–regressive processes.     

A new approach to constant term identities and Selberg-type integrals

Selberg-type integrals that can be turned into constant term identities for Laurent polynomials arise naturally in conjunction with random matrix models in statistical mechanics. Built on a recent idea of Karasev and Petrov we develop a general interpolation based method that is powerful enough to establish many such identities in a simple manner. The main consequence is the proof of a conjecture of Forrester related to the Calogero–Sutherland model. In fact we prove a more general theorem, which includes Aomoto's constant term identity at the same time. We also demonstrate the relevance of the method in additive combinatorics.     

Fluorescence Signal Amplification Strategies Based on DNA Nanotechnology for miRNA Detection

In this review,the most recent progresses in the field of fluorescence signal amplification strategies based on DNA nanotechnology for miRNA are summarized.The types of signal amplification are given and the principles of amplification strategies are explained,including rolling circle amplification(RCA),catalytic hairpin assembly(CHA),hybridization chain reaction(HCR)and DNA walker.Subsequently,the application of these signal amplification methods in biosensing and bioimaging are covered and described.Finally,the challenges and the outlook of fluorescence signal amplification methods for miRNA detection are briefly commented.     

Rational Design of a Two‐Photon Fluorogenic Probe for Visualizing Monoamine Oxidase A Activity in Human Glioma Tissues

Monoamine oxidases have two functionally distinct but structurally similar isoforms (MAO‐A and MAO‐B). The ability to differentiate them by using fluorescence detection/imaging technology is of significant biological relevance, but highly challenging with available chemical tools. Herein, we report the first MAO‐A‐specific two‐photon fluorogenic probe ( F1 ), capable of selective imaging of endogenous MAO‐A enzymatic activities from a variety of biological samples, including MAO‐A‐expressing neuronal SY‐SY5Y cells, the brain of tumor‐bearing mice and human Glioma tissues by using two‐photon fluorescence microscopy (TPFM) with minimal cytotoxicity.     

Aggregation‐Induced Emission: Recent Advances in Materials and Biomedical Applications

The concept of aggregation‐induced emission (AIE) has opened new opportunities in many research fields. Motivated by the unique feature of AIE fluorogens (AIEgens), during the past decade, many AIE molecular probes and AIE nanoparticle (NP) probes have been developed for sensing, imaging and theranostic applications with excellent performance outperforming conventional fluorescent probes. This Review summarizes the latest advancement of AIE molecular probes and AIE NP probes and their emerging biomedical applications. Special focus is to reveal how the AIE probes are evolved with the development of new multifunctional AIEgens, and how new strategies have been developed to overcome the limitations of traditional AIE probes for more translational applications via fluorescence imaging, photoacoustic imaging and image‐guided photodynamic/photothermal therapy. The outlook discusses the challenges and future opportunities for AIEgens to advance the biomedical field.