A Highly Selective and Sensitive Turn-On Fluorescent Chemosensor Based on Rhodamine 6G for Iron(III)

Recently, more and more rhodamine derivatives have been used as fluorophores to construct sensors due to their excellent spectroscopic properties. A rhodamine-based fluorescent and colorimetric Fe³⁺ chemosensor 3’,6’-bis(ethylamino)-2-acetoxyl-2’,7’-dimethyl-spiro[1H-isoindole-1,9’-[9H]xanthen]-3(2H)-one (RAE) was designed and synthesized. Upon the addition of Fe³⁺, the dramatic enhancement of both fluorescence and absorbance intensity, as well as the color change of the solution, could be observed. The detection limit of RAE for Fe³⁺ was around 7.98 ppb. Common coexistent metal ions showed little or no interference in the detection of Fe³⁺. Moreover, the addition of CN⁻ could quench the fluorescence of the acetonitrile solution of RAE and Fe³⁺, indicating the regeneration of the chemosensor RAE. The robust nature of the sensor was shown by the detection of Fe³⁺ even after repeated rounds of quenching. As iron is a ubiquitous metal in cells and plays vital roles in many biological processes, this chemosensor could be developed to have applications in biological studies.     

Positively charged liposomes consisting of the KTTKS pentapeptide conjugated with rhodamine increase rhodamine toxicity in E. coli and zebrafish embryo

Liposomes composed of cell‐penetrating peptide derivatives increased transport across the cell membrane. Conjugating rhodamine to a cell‐penetrating peptide increased the toxicity of rhodamine in E. coli and zebrafish embryos. A similar total protein inhibition pattern with different intensities, indicating that the interaction pathways of the rho‐KTTKS‐CONH₂ monomer and liposomes were the same. It suggests that the rho‐KTTKS‐CONH₂ liposomes showed higher toxicity because better transport across the cell membrane increased the effective concentration inside cells. The staining of zebrafish embryos using rho‐KTTKS‐CONH₂ liposomes showed a longer retention time, suggesting that it can penetrate deeper tissues or organs in zebrafish.     

PW_(11)O_(39)Co(Ⅱ)(H_2O)~(5-)的均相及异相体系可见光催化性能研究

以模型污染物罗丹明B(RhB)的光降解为探针,评估了Keggin型钴取代杂多阴离子PW11O39Co髤(H2O)5-(PW11Co)及其异相体系PW11Co/D301R的可见光催化活性,提出了光催化反应的机理,同时考察了催化剂用量、溶液酸度以及溶液中PW11Co和RhB的相互作用对RhB可见光催化降解速率的影响。实验结果表明,PW11Co均相体系及其异相体系PW11Co/D301R对RhB的可见光降解均有较高的光催化活性,但PW11Co/D301R的光催化活性更高。导致RhB降解的主要是羟基自由基。与PW11Co均相体系相比,在PW11Co/D301R异相体系中由于PW11Co与RhB的配位作用大为减弱,同时D301R对RhB具有富集作用,因而大大提高了RhB的光催化降解速率。     

CdS@g-C3N4复合核壳纳米微粒的制备与光催化性能

采用水热法,在乙二胺和EDTA-2Na作用下,成功制备了CdS@g-C3N4复合核壳纳米微粒,并探讨了其生长机理。结果显示:CdS@g-C3N4复合核壳纳米微粒的比表面积是纯CdS纳米颗粒的14.0倍,具有良好的光催化活性和光稳定性。当反应条件为180℃、4 h、CdS/g-C3N4质量比1.9∶1时,CdS@g-C3N4的可见光催化性能最好,300 W氙灯光照2 h,RhB的降解率达95.2%,明显高于纯CdS。重复使用3次后,CdS@g-C3N4形貌、结构及光催化性能无明显变化。     

185 nm UV降解水中4-CP、4-NP和Rh B的研究

本文以对氯苯酚(4-CP)、对硝基苯酚(4-NP)和罗丹明B(Rh B)为模型有机物(以4-CP和4-NP为小分子模型有机物,以Rh B为大分子模型有机物),分别研究了185 nm UV对水中这3种模型有机物的降解规律、性能和效果.研究结果表明,185 nm UV直接对水中4-CP、4-NP和Rh B有很好的降解效果.研究内容包括:185 nm UV降解模型有机物的浓度、TOC(Total organic carbon)浓度、185 nm UV降解模型有机物过程中溶液pH及电导率变化、以及降解模型有机物过程中产生的无机离子等几个方面.     

行和列和为常量的(0,1)-矩阵的计数

Let fs,t(m,n) be the number of (0,1) - matrices of size m x n such that each row has exactly s ones and each column has exactly t ones (sm = nt). How to determine fs,t(m,n)? As R. P. Stanley has observed (Enumerative CombinatoricsⅠ(1997), Example 1.1.3), the determination of fs,t(m, n) is an unsolved problem, except for very small s, t. In this paper the closed formulas for f2,2(n,n), f3,2(m,n), f4,2(m,n) are given. And recursion formulas and generating functions are discussed.     

超声MnO2联用降解丁基罗丹明B染料

采用超声MnO2体系降解丁基罗丹明B染料,考察了pH值、声强、MnO2投加量等因素对染料降解过程的影响。实验结果表明,溶液pH=3.0,MnO2投加量为1.5g/L,声强=40.7W/cm2,超声辐照10mg/L的罗丹明B溶液48m in,染料的脱色率为98.73%;超声和MnO2的协同效应在酸性条件下较为明显,溶液中产生大量.OH强化了对染料的声化学脱色和降解过程;丁基罗丹明B的超声降解过程以自由基的氧化反应为主,服从动力学一级反应。     

荧光各向异性法均相检测酸性、中性和碱性介质中的蛋白酶

荧光各向异性;罗丹明;蛋白酶;胰蛋白酶;胃蛋白酶;菠萝蛋白酶;蛋白酶抑制剂     

高效液相色谱-串联质谱法检测食品中的草甘膦及其主要代谢物氨甲基膦酸残留

建立了高效液相色谱-串联质谱测定植物产品(大豆、大米、小麦、蔬菜、水果、茶叶等)、动物肉类产品、水产品、板栗、蜂蜜等产品中草甘膦(PMG)及其主要代谢物氨甲基膦酸(AMPA)残留量的方法。样品经水提取后用二氯甲烷除去其中的脂肪,再经阳离子交换柱(CAX)净化,用 9-芴基甲基氯仿(FMOC-Cl)衍生化,采用多反应监测技术所确定的定性离子对其进行定性,同位素内标法定量。方法的定量检测低限为0.05 mg/kg,线性范围为0.20～10 μg/L,各种基质下PMG和AMPA的平均加标回收率为80.0%～104%,相对标准偏差为6.7%～18.2%。     

罗丹明B内酯单晶的生长及晶体结构

从含有罗丹明B的溶胶-凝胶中首次水热合成了罗丹明B内酯的单晶,并测定了其晶体结构。每个不对称单位含有两个独立分子。