CO2鼓泡法可控制备单层中空CaCO3微球:染料负载及细胞生物成像

在L-蛋氨酸（L-Met）的导向下,可控制备了一种单层中空CaCO₃微球。考察了L-Met的加入量、CO₂流速和反应温度等重要参数对CaCO₃形貌、尺度和晶相的影响。作为一种客体分子载体,该单层中空CaCO₃微球可负载罗丹明B（RhB）,得到一种发光复合材料（RhB@hollow-CaCO₃）。RhB@hollow-CaCO₃）对A-549肺癌细胞（A549 LCCs）和HO8910人卵巢癌细胞（HO8910 OCCs）表现出良好的生物相容性。     

Effect of surface and interlayer structure on the fluorescence of rhodamine B-montmorillonite: modeling and experiment

The surface and interlayer structure of rhodamine B (RhB)-montmorillonite for various guest concentrations has been studied using a combination of X-ray powder diffraction and molecular modeling (molecular mechanics and molecular dynamics) in the Cerius(2) modeling environment. The joint effect of surface and interlayer structure on the fluorescence spectrum has been observed and discussed in relation to the position and orientation of RhB(+) cations with respect to the silicate layer. Structural analysis showed that the surface and interlayer structures are different as to the arrangement of RhB(+) cations, and both of them strongly depend on the guest concentration in the intercalation solution and on the method of preparation. The repeated intercalation of montmorillonite by rhodamine B used in the present work allowed obtaining RhB-montmorillonite in the maximum degree of ion exchange for every sample.     

Loading of a Coordination Polymer Nanobelt on a Functional Carbon Fiber: A Feasible Strategy for Visible‐Light‐Active and Highly Efficient Coordination‐Polymer‐Based Photocatalysts

To improve the photocatalytic properties of coordination polymers under irradiation in the visible‐light region, coordination polymer nanobelts (CPNB) were loaded on functional carbon fiber (FCF) through the use of a simple colloidal blending process. The resulting coordination polymer nanobelt loaded functional carbon fiber composite material (CPNB/FCF) exhibited dramatically improved photocatalytic activity for the degradation of rhodamine B (RhB) under visible‐light irradiation. Optical and electrochemical methods illustrated the enhanced photocatalytic activity of CPNB/FCF originated from high separation efficiency of photogenerated electrons and holes on the interface of CPNB and FCF, which was produced by the synergy effect between them. In the composite material, the role of FCF could be described as photosensitizer and good electron transporter. For FCF, the number of functional groups on its surface has a significant influence on the photocatalytic performance of the resulting CPNB/FCF composite material, and an ideal FCF carrier was obtained as a highly efficient CPNB/FCF photocatalyst. CPNB/FCF showed outstanding stability during the degradation of rhodamine B (RhB); thus, the material is suitable for use as a photocatalyst in the treatment of organic dyes in water.     

无溶剂法大量制备高效红光碳点及其在白光器件中的应用

以邻苯二胺、 2,5-二氨基苯磺酸和三氯化铝为原料, 通过无溶剂法大量制备了高效的红色荧光碳点 (R-CDs). 制得的碳点尺寸大约为2.4 nm, 含有13%的氮元素, 主要由高度石墨化的碳核及覆盖在其表面的大量官能团构成. 在不同的波长光激发下, 碳点在乙醇溶液中表现出不依赖于激发的红光发射, 其荧光峰位于 704 nm, 最大量子产率达到22%. 由于R-CDs具有优异的光学性质, 利用其构筑了紫外光激发的碳基白色发光二极管, 其色坐标为(0.33, 0.33), 非常接近自然光. 该研究为高效红色荧光碳点的大量制备提供了一种新路径, 同时拓宽了其在白光器件中的应用.     

Chemiluminescence behavior based on oxidation reaction of rhodamine B with cerium(IV) in sulfuric acid medium

The chemiluminescence (CL) of the rhodamine B (RhB)-cerium(IV) system was investigated by flow-injection. Rhodamine B was suggested to be a suitable chemiluminescent reagent in acidic conditions. When the concentration of rhodamine B was 100 mg l⁻¹ and cerium sulfate was 1.6 mmol l⁻¹ in sulfuric acid, the chemiluminescent intensity was found to be highest by using 0.3 mol l⁻¹ sulfuric acid as a carrier solution. The particular chemiluminescent system could tolerate such distinct acidic environments that it was utilized for detecting many compounds that are stable in acidic solutions. Furthermore, by virtue of IR, UV-Vis and luminescence spectroscopic measurements, the chemiluminescent behavior of rhodamine B was studied and a possible mechanism for this chemiluminescent reaction was proposed. The emitter was affirmed to be a radical species due to one of the oxidation products of RhB; the chemiluminescent emissive wavelength was about 425 nm.     

新型超分子复合发光材料四足配体铕配合物-蒙脱土的插层组装及发光性质

通过离子交换反应将四足配体铕配合物[EuL(NO3)]2+[L=1,1,1’,1’-四(吡啶-2-羧酸酯基)联三甲基丙烷]插层组装到蒙脱土(MT)层板间, 制备出一种新型的超分子复合发光材料[EuL(NO3)]2+-MT. 用元素分析、XRD、FTIR、UV-Vis和热分析对材料进行了表征, 并对其荧光性质进行了研究. 结果表明, 复合材料保持了蒙脱土良好的层柱结构特征, 其层间距d(001)值与插层配离子的直径吻合得较好, 配离子以单层形式分布于蒙脱土层板间. 在紫外光激发下, 复合材料发出较强的Eu3+特征荧光, 其相对荧光强度、荧光单色性和荧光寿命大大优于相应配合物的乙醇溶液. 复合材料中配合物的发光性能、光稳定性和热稳定性较纯配合物有明显提高.     

Photodegradation of rhodamine B dye using a microwave electrodeless UV lamp (MWUVL)

The photodegradation of organic dye rhodamine B (RhB) in an aqueous solution was studied using a microwave electrodeless UV lamp (MWUVL). The 185 nm vacuum UV (VUV) intensity of the MWUVL amounted to 12% of the total UV output, about 1.7 times as high as that of the con ventional low-pressure mercury lamp. An acidic condition was preferred for the degradation of RhB. Precipitate was generated during RhB degradation when the initial concentration of RhB solution was above 60 mg · L⁻¹. For 100 mg · L⁻¹ RhB at pH 4.0, the mass of precipitate produced was nearly half of the initial amount of RhB in the solution after irradi ation for 75 min. The corresponding degradation ratio of RhB reached up to 99.4% and COD reduced 77.4%. The photo degradation of RhB is mainly achieved by direct photolysis of RhB by 185 nm and OH radical oxidation. __________ Translated from Journal of Fudan University (Natural Science), 2006, 45(6): 726–731 [译自: 复旦学报 (自然科学版)]     

Hollow Polyaniline Microspheres with Conductive and Fluorescent Function

Summary: Salicylic acid‐doped hollow polyaniline and rhodamine B composite spheres (1.9–3.3 µm in average diameter) with a high conductivity (≈10⁻¹ S · cm⁻¹) and a strong fluorescence were synthesized by a template‐free method. The morphologies, electrical and fluorescent properties of the hollow composite microspheres can be adjusted by changing the content of RhB in the composites opening a simple route to preparing multi‐functionalized micro/nanostructures.

SEM and TEM images of PANI‐SA/RhB synthesized under concentration of 1 × 10⁻³ M RhB.     

Hierarchical porous cellulose/activated carbon composite monolith for efficient adsorption of dyes

Cheap and efficient adsorbents to remove contaminants of toxic dye molecules from wastewater are strongly in demand for environmental reasons. This study provides a novel design of a monolithic adsorbent from abundant materials via a facile synthetic procedure, which can greatly reduce the problems of the tedious separation of adsorbents from treated wastes. A hierarchically porous cellulose/activated carbon (cellulose/AC) composite monolith was prepared by thermally-induced phase separation of cellulose acetate in the presence of AC, using a mixture of DMF and 1-hexanol, followed by alkaline hydrolysis. The composite monolith had alarge specific surface area with mesopore distribution. It not only showed high uptake capacity towards methylene blue (MB) or rhodamine B (RhB) but could also simultaneously adsorb MB and RhB from their mixture, in which the adsorption of one dye was not influenced by the other one. Remarkable effects of solution pH, initial concentration of dye (C ₀), contact time, adsorbent dosage and temperature on the adsorption of MB and RhB onto the composite monolith were demonstrated. The binding data for MB and RhB adsorption on the composite monolith fitted the Freundlich model well, suggesting a heterogeneous surface of the composite monolith. The monolith could retain around 90% of its adsorption capacity after 8 times reuse. These data demonstrate that the cellulose/AC composite monolith has a large potential as a promising adsorbent of low cost and convenient separation for dye in wastewater.     

Polyaspartamide–Polylactide Graft Copolymers with Tunable Properties for the Realization of Fluorescent Nanoparticles for Imaging

Here, the synthesis and the characterization of novel amphiphilic graft copolymers with tunable properties, useful in obtaining polymeric fluorescent nanoparticles for application in imaging, are described. These copolymers are obtained by chemical conjugation of rhodamine B (RhB) moieties, polylactic acid (PLA), and O‐(2‐aminoethyl)‐O′‐methyl poly(ethylene glycol) (PEG) on α,β‐poly(N‐2‐hydroxyethyl)‐d,l ‐aspartamide (PHEA). In particular, PHEA is first functionalized with RhB to obtain PHEA–RhB with a derivatization degree in RhB (DD_RhB) equal to 0.55 mol%. By varying the reaction conditions, different amounts of PLA are grafted on PHEA–RhB to obtain PHEA‐RhB‐PLA with DD_PLA equal to 1.9, 4.0, and 6.2 mol%. Then, PEG chains are grafted on PHEA‐RhB‐PLA derivatives to obtain PHEA‐RhB‐PLA‐PEG graft copolymers. The preparation of polymeric fluorescent nanoparticles with tunable properties and spherical shape is described by using PHEA‐RhB‐PLA‐PEG with DD in PLA and PEG equal to 4.0 and 4.9 mol%, by following easily scaling up processes, such as emulsion‐solvent evaporation and high pressure homogenization (HPH)‐solvent evaporation techniques.

     

Orange-emitting bimetallic nanoclusters combined with cyan-emitting Fe@TAOH as white light-emitting materials

White-light-emitting diodes（WLEDs） possess many merits, such as high efficiency and stability. Developing cost-effective, environmentally friendly, high-performance luminophores to achieve high-quality,full-spectrum, white lighting is of great importance to the construction and progress of WLEDs. In this work, solid-state, highly luminescent orange-emitting nanoclusters（MgCl₂-Lys-Ag/Au NCs） were prepared via the salt-induced precipitation of Lys-Ag/Au NCs from solution, which showed a...     

Highly sensitive electrochemical sensing based on 2-hydroxypropyl-β-cyclodextrin-functionalized graphene nanoribbons

In this communication, 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) funtionalized graphene nanoribbons (HP-β-CD/GNRs) were prepared for the first time by using a simple wet chemical strategy, and then, the HP-β-CD/GNRs were applied for constructing electrochemical sensors for three representative analytes (p-aminophenol, p-AP; l-tyrosine, Tyr; rhodamine B, RhB). Owing to the synergetic effects of GNRs (excellent electrochemical properties and large surface area) and HP-β-CD (high host–guest recognition and enrichment capability), the highly sensitive electrochemical sensing platforms of three analytes were established by using HP-β-CD/GNRs modified electrode, and the detection limits were 0.0008, 0.003, and 0.001 μM for p-AP, Tyr, and RhB, respectively.     

Luminescent and Magnetic Tb-MOF Flakes Deposited on Silicon

The synthesis of a terbium-based 2D metal–organic framework (MOF), of formula [Tb(MeCOO)(PhCOO)₂] (1), a crystalline material formed by neutral nanosheets held together by Van der Waals interactions, is presented. The material can be easily exfoliated by sonication and deposited onto different substrates. Uniform distributions of Tb-2D MOF flakes onto silicon were obtained by spin-coating. We report the luminescent and magnetic properties of the deposited flakes compared with those of the bulk. Complex 1 is luminescent in the visible and has a sizeable quantum yield of QY = 61% upon excitation at 280 nm. Photoluminescence measurements performed using a micro-Raman set up allowed us to characterize the luminescent spectra of individual flakes on silicon. Magnetization measurements of flakes-on-silicon with the applied magnetic field in-plane and out-of-plane display anisotropy. Ac susceptibility measurements show that 1 in bulk exhibits field-induced slow relaxation of the magnetization through two relaxation paths and the slowest one, with a relaxation time of τ_lf ≈ 0.5 s, is assigned to a direct process mechanism. The reported exfoliation of lanthanide 2D-MOFs onto substrates is an attractive approach for the development of multifunctional materials and devices for different applications.     

Cucurbiturils brighten Au nanoclusters in water

Gold nanoclusters (AuNCs) with well-defined atomically precise structures present promising emissive prospects for excellent biocompatibility and optical properties. However, the relatively low luminescence efficiency in solutions for most AuNCs is still a perplexing issue to be resolved. In this study, a facile supramolecular strategy was developed to rigidify the surface of FGGC-AuNCs by modifying transition rates in excited states via host–guest self-assembly between cucurbiturils (CBs) and FGGC (Phe–Gly–Gly–Cys peptide). In aqueous solutions, CB/FGGC-AuNCs presented an extremely enhanced red phosphorescence emission with a quantum yield (QY) of 51% for CB[7] and 39% for CB[8], while simple FGGC-AuNCs only showed a weak emission with a QY of 7.5%. Furthermore, CB[7]/FGGC-AuNCs showed excellent results in live cell luminescence imaging for A549 cancer cells. Our study demonstrates that host–guest self-assembly assisted by macrocycles is a facile and effective tool to non-covalently modify and adjust optical properties of nanostructures on ultra-small scales.

A host–guest self-assembly approach was developed to brighten Au₂₂(FGGC)₁₈ nanoclusters between CB[n] (n = 7, 8) and FGGC peptide in aqueous solutions.     

The rhodamine B intercalation of montmorillonite

Using photometric methods the dissociation constants and weight fractions of rhodamine B dimer in water solutions at different concentrations were determined. The montmorillonite (SWy) samples were fully intercalated with rhodamine B (RhB) solutions at various monomer/dimer ratios. The amount of rhodamine B in fully intercalated montmorillonite (RhB-SWy) increases with increasing concentration of dye in water solutions, i.e., with increasing dimer/monomer ratio. The sum of exchangeable guest cations in RhB-SWy is approximately constant (0.900 meq g(-1)) for all samples, because RhB-SWy samples with prevailing dye monomer also contain higher amounts of non-exchanged alkali elements. The experimental data are supported by calculated structure models that illustrate the changes in RhB-SWy structure depending on monomeric and/or dimeric arrangement of guests. The analysis of the calculated structure models confirmed the existence of two phases with different basal spacings, d approximately 1.8 and approximately 2.3 nm, revealed by X-ray diffraction.     

The Uncommon Channel‐Based Ln‐MOFs for Highly Selective Fe3+ Detection and Superior Rhodamine B Adsorption

Two new isostructural 3D lanthanide–organic frameworks [H₂N(Me)₂] [Ln₃(OH)(bpt)₃(H₂O)₃] (DMF)₂?(H₂O)₄ ( 1‐Ln ; Ln=Sm and Eu) with a 1D channel (25 Å) have been successfully assembled from the rare trinuclear [Ln₃(OH)(COO)₉] clusters and biphenyl‐3,4′,5‐tricarboxylic acid (H₃bpt) and exhibit high stability towards water in the pH range 3–10. MOF 1‐Eu is a promising luminescent probe for sensing Fe³⁺ in aqueous solution and is also selective towards rhodamine B (RhB) with a superior adsorption capacity of 735 mg g^?1, which is the highest among the reported Ln‐MOFs for RhB removal so far. Periodic DFT calculations further confirmed the selective adsorption of rhodamine B over other dyes.     

共模板法一步合成绣球状BiOCl/Br固溶体光催化剂

以乙二醇/十二烷基三甲基溴化铵(EG/DTAB)为共模板剂,一步制得BiOCl/Br的固溶体光催化剂,利用X射线衍射仪、扫描电子显微镜、能谱仪、N2吸附-脱附仪和紫外-可见漫反射光谱仪进行了表征.结果表明,与采用溶剂热法制得的BiOCl分级微球相比,采用EG/DTAB共模板法制得的BiOCl/Br固溶体具有更明显的分层结构,呈绣球状.同时,DTAB的Br-插入到BiOCl的晶格中,形成固溶体,减小了禁带宽度.绣球状BiOCl/Br固溶体具有比商用P25、二维BiOCl纳米片和三维BiOCl分级微球更优异的可见光间接敏化降解染料性能,当nDTAB/nKCl=0.75时,制得的BiOCl/Br固溶体8 min内在可见光下对罗丹明B(Rh B)的降解率达到97.2%;1 h后在可见光下对甲基橙(MO)的降解率达到83.6%.     

Mitocanic Di- and Triterpenoid Rhodamine B Conjugates

The combination of the “correct” triterpenoid, the “correct” spacer and rhodamine B (RhoB) seems to be decisive for the ability of the conjugate to accumulate in mitochondria. So far, several triterpenoid rhodamine B conjugates have been prepared and screened for their cytotoxic activity. To obtain cytotoxic compounds with EC₅₀ values in a low nano-molar range combined with good tumor/non-tumor selectivity, the Rho B unit has to be attached via an amine spacer to the terpenoid skeleton. To avoid spirolactamization, secondary amines have to be used. First results indicate that a homopiperazinyl spacer is superior to a piperazinyl spacer. Hybrids derived from maslinic acid or tormentic acid are superior to those from oleanolic, ursolic, glycyrrhetinic or euscaphic acid. Thus, a tormentic acid-derived RhoB conjugate 32, holding a homopiperazinyl spacer can be regarded, at present, as the most promising candidate for further biological studies.     

客体小分子在超分子有机凝胶体系中的扩散释放

采用二(4-硬脂酰胺基苯基)甲烷(BSAPM)为凝胶剂制备了含有小分子水杨酸和若丹明B的1,1,2-三氯乙烷(TCE)超分子有机凝胶. 以超分子有机凝胶作为主体, 客体小分子水杨酸和若丹明B可轻微降低超分子有机凝胶的相转变温度(T_GS). 用紫外-可见光度法研究了超分子凝胶中两种客体小分子在静态下的扩散释放. 结果表明其释放率随凝胶剂浓度的增加而降低. 客体小分子的体积大小对其释放有明显的影响, 分子体积较大的若丹明B的释放率低于分子体积较小的水杨酸. 另外, 若丹明B的扩散系数也低于水杨酸, 且随凝胶剂浓度的增加, 这种趋势更为明显. 两种客体分子的累积释放率与时间的平方根成良好的线性关系, 符合Higuchi方程, 属扩散控制的Fickian释放机理.     

Solid-emissive rhodamine: hydrogen bonding-assisted efficient intermolecular fluorescence resonance energy transfer in the solid state

Solid-emissive rhodamine complexes are obtained by mixing commercial rhodamine B (RhB) with the recently developed solid-emissive boron 2-(2′-pyridyl)imidazole (BOPIM) derivatives. The formation of intermolecular hydrogen bonds between RhB and BOPIM dyes plays a key role in the emission of RhB in the solid state. The disappearance of emissions from BOPIM dyes indicates the occurrence of efficient intermolecular fluorescence resonance energy transfer (FRET). The hydrogen bond also helps prevent the intermolecular interaction between the carboxyl moieties on RhB to alleviate concentration-induced fluorescence quenching because the emission of the complexes can be directly lightened by excitation at the RhB absorption (510 nm). Our results indicate that intermolecular FRET assisted by non-covalent interactions can be an efficient tool for constructing red or near-infrared solid emitters.