Dalian University of Technology

About: Dalian University of Technology is a education organization based out in Dalian, China. It is known for research contribution in the topics: Catalysis & Finite element method. The organization has 60890 authors who have published 71921 publications receiving 1188356 citations. The organization is also known as: Dàlián Lǐgōng Dàxué.

Graphene oxide modified g-C3N4 hybrid with enhanced photocatalytic capability under visible light irradiation

Abstract: Graphene oxide modified g-C3N4 (GO/g-C3N4) with efficient photocatalytic capability under visible light irradiation was fabricated by sonochemical approach. Transmission electron microscopy images demonstrated that GO was two-dimensional sheets with chiffon-like ripples and the g-C3N4 possessed a layered structure. GO was overlaid on the surface of g-C3N4 in the GO/g-C3N4 hybrids. The UV–vis diffuse reflectance spectra showed that the GO/g-C3N4 hybrid had intense optical absorption in the visible light region. Photoluminescence spectra confirmed that the separation efficiency of photogenerated charge in GO/g-C3N4 was more intensive than pristine g-C3N4, indicating the GO acts as a separation centre and electron acceptor in the GO/g-C3N4 hybrid. The effective photogenerated charge separation efficiency lead to a remarkable improvement in the visible light photocatalysis. The pseudo-first-order kinetic constants of photocatalytic degradation of rhodamine B and 2, 4-dichlorophenol under visible light irradiation with GO/g-C3N4 were 3.80 and 2.08 times as large as that with pristine g-C3N4, respectively. This work indicates that the metal-free GO/g-C3N4 hybrid photocatalyst is a promising material in waste control, and GO could be an excellent material to combine with other semiconductors to make composites.

Fluorescent Probes for Sensing and Imaging within Specific Cellular Organelles.

Abstract: Fluorescent probes have become powerful tools in biosensing and bioimaging because of their high sensitivity, specificity, fast response, and technical simplicity. In the last decades, researchers have made remarkable progress in developing fluorescent probes that respond to changes in microenvironments (e.g., pH, viscosity, and polarity) or quantities of biomolecules of interest (e.g., ions, reactive oxygen species, and enzymes). All of these analytes are specialized to carry out vital functions and are linked to serious disorders in distinct subcellular organelles. Each of these organelles plays a specific and indispensable role in cellular processes. For example, the nucleus regulates gene expression, mitochondria are responsible for aerobic metabolism, and lysosomes digest macromolecules for cell recycling. A certain organelle requires specific biological species and the appropriate microenvironment to perform its cellular functions, while breakdown of the homeostasis of biomolecules or microenvironmental mutations leads to organelle malfunctions, which further cause disorders or diseases. Fluorescent probes that can be targeted to both specific organelles and biochemicals/microenvironmental factors are capable of reporting localized bioinformation and are potentially useful for gaining insight into the contributions of analytes to both healthy and diseased states. In this Account, we review our recent work on the development of fluorescent probes for sensing and imaging within specific organelles. We present an overview of the design, photophysical properties, and biological applications of the probes, which can localize to mitochondria, lysosomes, the nucleus, the Golgi apparatus, and the endoplasmic reticulum. Although a diversity of organelle-specific fluorescent stains have been commercially available, our efforts place an emphasis on improvements in terms of low cytotoxicity, high photostability, near-infrared (NIR) emission, two-photon excitation, and long fluorescence lifetimes, which are crucial for long-time tracking of biological processes, tissue and body imaging with deep penetration and low autofluorescence, and time-resolved fluorescence imaging. Research on fluorescent probes with both analyte responsiveness and organelle targetability is a new and emerging area that has attracted increasing attention over the past few years. We have extended the diversity by developing organelle-specific responsive probes capable of detecting changes in biomolecular levels (reactive oxygen species, fluoride ion, hydrogen sulfide, zinc cation, thiol-containing amino acids, and cyclooxygenase-2) and the microenvironment (viscosity, polarity, and pH). Future research should give more considerations of the "low-concern" organelles, such as the Golgi apparatus, the endoplasmic reticulum, and ribosomes. In addition, given the tiny sizes of subcellular organelles (20-1000 nm), we anticipate that clearer visulization of the cellular events within specific organelles will rely on super-resolution optical microscopy with nanoscopic-scale resolution.

Macro-/micro-environment-sensitive chemosensing and biological imaging

Abstract: Environment-related parameters, including viscosity, polarity, temperature, hypoxia, and pH, play pivotal roles in controlling the physical or chemical behaviors of local molecules. In particular, in a biological environment, such factors predominantly determine the biological properties of the local environment or reflect corresponding status alterations. Abnormal changes in these factors would cause cellular malfunction or become a hallmark of the occurrence of severe diseases. Therefore, in recent years, they have increasingly attracted research interest from the fields of chemistry and biological chemistry. With the emergence of fluorescence sensing and imaging technology, several fluorescent chemosensors have been designed to respond to such parameters and to further map their distributions and variations in vitro/in vivo. In this work, we have reviewed a number of various environment-responsive chemosensors related to fluorescent recognition of viscosity, polarity, temperature, hypoxia, and pH that have been reported thus far.