NEW JOURNAL OF CHEMISTRY
·
2015
·Vol. 39
·期 7
·5750-5758
·
IF 3.086
Yinghui Bian,Jinshe Chen,Shaotang Xu,Yulu Zhou,Lijun Zhu,Yuzhi Xiang,Daohong Xia
Two novel metal-free phthalocyanines have been designed and synthesized, namely tetra{[1H-benzo(d)imidazol-2-yl]thiol}phthalocyanine (TBIT-Pc) and tetra{[benzo(d)thiazol-2-yl]thiol}phthalocyanine (TBTT-Pc). These two compounds showed similar structures, while imidazolyl-NH in the substitutes of TBIT-Pc could form more hydrogen bonds. TBIT-Pc and TBTT-Pc were fully characterized by elemental analysis, 1H NMR, MALDI-TOF MS, FT-IR and the UV-Vis absorption spectrum. The self-assembly properties of TBIT-Pc and TBTT-Pc were comparatively studied. TBIT-Pc and TBTT-Pc were present as monomers in DMF in the concentration range of 9.04–20.3 μM. Depending mainly on the intermolecular hydrogen bonding (N–H⋯N) between benzimidazole substitutes, “head-to-tail” J-aggregates of TBIT-Pc were formed in DMSO, while there was no aggregation of TBTT-Pc in the same solvent. “Face-to-face” H-aggregates of TBIT-Pc and TBTT-Pc were formed with the addition of water to the solutions of DMSO, and the degree of aggregation increased with the introduction of H-bonds (N–H⋯N) in the benzimidazole substitutes of TBIT-Pc. The atomic force microscope (AFM) image and dynamic light scattering (DLS) displayed the formation of well-defined nanoparticles with a diameter of ca. 30 ± 15 nm with J-type aggregation of TBIT-Pc. And the dendritic nanostructures with H-aggregates of TBIT-Pc and TBTT-Pc with different size were observed from transmission electron microscopy (TEM) images. The possible mechanism of the effect of H-bonds on the formation of J-aggregates of TBIT-Pc and the H-aggregation of TBIT-Pc and TBTT-Pc was also discussed. In the formation process of aggregates, H-bonds and π–π interaction may be the dominant factors. In addition, the nanostructures fabricated from TBIT-Pc and TBTT-Pc showed good semiconducting properties revealed by current–voltage measurements.
研究领域:
超分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2020
·Vol. 41
·期 14
·2000198
·
IF 4.886
Xu Yu,Yan-Cai Gao,Hong-Wei Li,Yuqing Wu
Unlike normal conversion from aggregation caused quenching (ACQ) to aggregation induced emission enhancement (AIEE) by introducing aromatic rotors tuning aggregation modes, in this study, it is achieved through a supramolecular assembly with polymer. Thus, it provides an easy approach for the inhibition of unwanted H-aggregation between luminogens. As a kind of flavonoid, morin has shown great potential in therapeutics. However, its poor solubility and weak emission in aqueous solution greatly limit its bioapplications. When morin is dissolved in aqueous solution, the presence of 30 × 10 −6 m polyethyleneimine (PEI) induces significant emission enhancement and bathochromic shift. Consequently, the quantum yield (QY) of 24.5% is either achieved by assembling with PEI, versus 0.76% of its ACQ state composed of H-aggregation in aqueous solution. Particularly, the in-depth mechanism studies reveal that it is the assembly with PEI that disassociates the H-aggregation in aqueous solution and further restricts the stretching and/or rotation of morin, which eventually reduce the nonradiative decays and enhance the emission. Therefore, the present study reports a unique phenomenon of AIEE effects on morin. Particularly the in-depth investigation on intrinsic mechanisms will highlight and greatly expand the development of more luminogens from traditional Chinese herbals.
研究领域:
化学
·
生物医学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemistrySelect
·
2022
·Vol. 7
·期 44
·e202203402
·
IF 2.307
Xiaoying Ma,Lei Shi,Yao Fu,Buyue Zhang,Xiufeng Zhang
Graphical The cyclic induction of H-aggregates and J-aggregates can be achieved by adding rare earth ions, methanol and EDTA to the MTC solution. The intuitive color expression can be used as a La 3+ detection switch. In recent years, the assembly of cyanine dye supramolecular aggregates has been a very important task because its photophysical and photochemical properties are widely used in many scientific fields, such as, materials, biomedical and industrial. In this work, H- and J-aggregates of cyanine dyes were constructed under controllable conditions, and a simple method was developed to achieve cycle induction around these aggregates which induced by rare earth ions, and the process can be repeated for many cycles. Assembly and circulation induce these aggregates to be easy to manipulate and identify, which can be directly observed with the naked eye. This simple supramolecular assembly provides another direction in the field of sensors, while bringing a new idea to the control of supramolecular aggregates.
研究领域:
材料科学
·
生物医学
·
工业化学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2023
·
IF 10.9
Cheng-Long Shen,Qing Lou,Kai-Kai Liu,Guang-Song Zheng,Run-Wei Song,Jin-Hao Zang,Lin Dong,Chong-Xin Shan
Control of aggregation plays an important role in the photophysical behavior of luminescent nanomaterials . Herein, the concentration-dependent self-assembled hybrid of carbon nanodots (CDs) with the alteration spectral characters of H-/J-aggregation were observed. In detail, the CDs aging under different conditions presented obvious spectral variations ranging from visible to near-infrared regions, accompanied by the spontaneous evolution of nanoaggregates from CD nanoparticles . Theoretical calculations and experimental results confirmed the inhomogeneous surface functional groups could render CDs into nanoaggregates with the H- or J-aggregation through intraparticle or interparticle interaction, inducing the discrepant surface-confined charges in these intraparticle nanoaggregates and further contributing to their shift of absorption and emission bands. With the novel aggregation regulation, the CDs exhibited a tunable increase in their photothermal and photodynamic capability in comparison to their original counterparts. These findings shed a new light on the understanding of the photophysical behaviors for the self-assembled hybrid of CDs with the concept of supramolecular engineering.
研究领域:
纳米材料科学
·
超分子工程学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2017
·
IF 2.714
Jingwen Song,Kai Ma,Tifeng Jiao,Ruirui Xing,Lexin Zhang,Jingxin Zhou,Qiuming Peng
Graphene oxide (GO)-based nanocomposite films via facile and appropriate self-assembly methods have demonstrated many potential applications in wide fields. This study demonstrates a facile and clean route to prepare graphene oxide-dye composite films using Langmuir-Blodgett (LB) technique at room temperature. By electrostatic interaction between cationic dye molecules and negatively charged GO sheets as well as π-π interactions, GO-dye composite LB films were formed spontaneously. As a soft platform for dye molecules, GO sheets induce dye molecules to self-assemble and form highly ordered structures containing H-aggregates and/or J-aggregates. The morphological characterization results show the formation of GO-dye composite films with smooth and dense surfaces. And the spectral results reveal that dye molecules stack in well-organized aggregates on the surface of GO sheets corresponding to monomers in bulk solution. The present research work about GO-dye composite films by LB method may provide new clues to prepare organized composite films and demonstrate potential applications in many fields.
研究领域:
材料科学
·
纳米科技
·
表面化学
·
胶体与界面科学
·
功能薄膜
✓ 已验证
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2020
·
IF 3.232
Chenxiao Yan,Qingqing Zhang,Heng Gao,Xiong Zheng,Tong Yang,Guoxiang Zheng,Xiaoshun Zhou,Yong Shao
DNA templated dye assemblies pave an easy way to regulate the optical properties of molecular aggregates. G-quadruplexes (G4s) provide versatile DNA platforms for the dye assemblies since their foldings can be easily tuned by cation ions and sequences. In this work, we found that the G4 handedness can be used to control the aggregate chirality of a dye of 3,3′-diethylthiacarbocyanine (DiSC 2 (3)). The left-handed and right-handed G4s can template the concurrent formation of the J- and H-aggregates of DiSC 2 (3) with emergence of the featured absorption spectra. However, the chiral J-aggregate of DiSC 2 (3) can be formed only on the left-handed G4s, while the chiral H-aggregate is otherwise grown only on the right-handed G4s, as confirmed by the induced circular dichroism (ICD) spectra with the characteristic splitting bands. Additionally, these G4s even at tens of nM level are efficient to produce these chiral aggregates, demonstrating the high sensitivity of G4s in creating these optically active dye assemblies. The possible growth sites of the aggregates are proposed by the sequence length-dependent assemblies. Our work will provide a new way to control the chiral assemblies of dye aggregates via the G4 handedness.
研究领域:
化学
·
材料科学
·
生物物理
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PARTICLE & PARTICLE SYSTEMS CHARACTERIZATION
·
2023
·
IF 2.7
Haoting Hou,Miao Wu,Mao Wang,Xirui Miao,Haichao Li,Yang Chen,Xudong Yang
Carbon dots have been widely noticed due to their excellent optical properties, such as good photostability and a wide excitation wavelength range. However, the emission peaks of most known carbon dots (CDs) are in the blue region, which hinders their extensive applications in long-wavelength emission. In this study, red-emitting carbon dots (RCDs) that are pH-responsive are synthesized using citric acid and urea as precursors, and their fluorescence intensity increased gradually with increasing solution pH from 1 to 12. A new mechanism based on H aggregation and Fermi energy level transfer is proposed to explain the pH-responsive emission of RCDs. In contrast to the narrow response range of most pH-sensitive CDs reported so far, the pH-responsive range of RCDs is large, especially in the alkaline range, and their pronounced red light emission is well visualized. The prepared carbon dots have the advantages of non-toxicity, low cost, and a wide pH response range. In addition, “rose” test paper and carbon dot PVA composite film, RCDs-PVA film, are made to demonstrate the visualization of carbon dots in pH detection. The “rose” test paper and carbon dot PVA still have good fluorescence intensity. The prepared carbon dots have good application prospects for pH detection.
研究领域:
材料科学
·
分析化学
·
纳米技术
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2022
·
IF 5.999
Lijun Ding,Jie Yang,Kangrui Yin,Hao Cheng,Jing Li,Changhu Xue
Liposomes are regarded as the ideal nanocarrier for concurrent or separate delivery of nutraceuticals in the food industries. Precise control of the structural stability is essential for the processing, storage, and nutrition delivery of liposomes. Astaxanthin was found to significantly affect the membrane stability of liposomes by inserting into the phospholipid bilayers in a similar way to cholesterol. Compared with cholesterol, astaxanthin could significantly improve the phase transition temperature, membrane fluidity , and membrane compactness of liposomes. Additionally, the membrane stability was well modulated by controlling the distribution patterns of astaxanthin (monomers, H- and J-aggregates) in bilayers. For instance, astaxanthin H-aggregates could endow the liposomal membrane with highest rigidity and compactness. Additionally, astaxanthin aggregates, especially J-aggregates could greatly improve storage stability of liposomes, thus providing a novel strategy to regulate and optimize the stability of liposomes for their diversified applications.
研究领域:
纳米技术
·
食品科学
·
药学
✓ 已验证
产品关联
DOI
PubMed
高影响因子