Query: cellulose, AIE

title: Aggregation Induced Emission (AIE) Labeled Cellulose Nanocrystals for the Detection of Nitrophenolic Explosives in Aqueous Solutions
abstract: Aggregation induced emission (AIE) active cellulose nanocrystals (TPE CNCs) were synthesized by attaching tetraphenylethylene (TPE) to cellulose nanocrystals (CNCs) The structure and morphology of TPE CNCs were characterized by FT IR, XRD, z potential measurements, elemental analysis, TEM, atomic force microscopy (AFM) and dynamic laser light scattering (DLS) Fluorescent properties of TPE CNCs were also further studied. Unlike aggregation caused quenching (ACQ) TPE CNCs emitted weak fluorescence in the dilute suspensions, while emitting efficiently in the aggregated states. The AIE mechanism of TPE CNCs was attributed to the restriction of an intramolecular rotation (RIR) process in the aggregated states. TPE CNCs displayed good dispersity in water and stable fluorescence, which was reported through the specific detection of nitrophenolic explosives in aqueous solutions by a fluorescence quenching assay. The fluorescence emissions of TPE CNCs showed quantitative and sensitive responses to picric acid (PA) 2,4 dinitro phenol (DNP) and 4 nitrophenol (NP) and the detection limits were 220, 250, and 520 nM, respectively. Fluorescence quenching occurred through a static mechanism via the formation of a nonfluorescent complex between TPE CNCs and nitrophenolic analytes. A fluorescence lifetime measurement revealed that the quenching was a static process. The results demonstrated that TPE CNCs were excellent sensors for the detection of nitrophenolic explosives in aqueous systems, which has great potential applications in chemosensing and bioimaging.

title: AIE active b diketones containing pyridiniums: fluorogenic binding to cellulose and water vapour recoverable mechanochromic luminescence
abstract: A series of pyridinium ring substituted b diketones were found to exhibit aggregation induced emission (AIE) and water vapour recoverable mechanochromic luminescence in the solid state. Certain water soluble b diketones could selectively bind to cellulose based materials, where strong fluorescence similar to AIE was turned on.

title: Aggregation induced white emission of lanthanide metallopolymer and its coating on cellulose nanopaper for white light softening
abstract: A series of metallopolymers containing two lanthanides (Poly Eu Tb, molar ratio of Eu3+/Tb3+ 1 1, 1 2, 1 4 and 1 8) have been synthesized via the coordination of Eu3+ and Tb3+ ions to terpyridine based polymers (Poly) At a high concentration (1 mg mL 1) in DMF, Poly Eu Tb with an optimal Eu3+/Tb3+ ratio (1 8) shows strong white light emission from the Poly backbone and Eu3+ and Tb3+ ions, but changes to very weak blue emission mainly from the Poly backbone when diluted to an extremely low concentration (0.1 mg mL 1) For typical aggregation induced emission (AIE) effects, a strong white light emission can be recovered along with the addition of 1,4 dioxane to the diluted DMF solution. Moreover, Poly Eu Tb is uniformly dispersed on the surface of cellulose nanopaper (CNFs) via a simple solution coating process, giving a new flexible cellulose nanopaper Poly Eu Tb CNFs. The new cellulose nanopaper characteristic of UV excited white light emission shows excellent haze properties (haze value as high as 98% and therefore could be applied as a substrate and light diffuser in the fabrication of soft white light emitting diodes (SWLEDs)

title: Fabrication of b cyclodextrin containing AIE active polymeric composites through formation of dynamic phenylboronic borate and their theranostic applications
abstract: Since the first discovery by Tang in 2001, aggregation induced emission (AIE) phenomenon has attracted considerable research interest in various fields. In this contribution, AIE active composites (named as An HPG b CD) have been fabricated via conjugation of AIE active compound An B(OH)2 and hyperbranched polyglycerol functionalized b cyclodextrin (HPG b CD) based on dynamic phenyl borate for the first time. The potential biomedical applications of these AIE active composites for biological imaging and drug delivery applications were further explored. The successful preparation of An HPG b CD composites was confirmed through a series of characterization techniques. The An HPG b CD composites possess great water dispersibility, low cytotoxicity, excellent fluorescence properties and uniform size and morphology, which make them promising for cell imaging. Furthermore, the cavities of An HPG b CD composites could be utilized for loading with doxorubicin for drug delivery applications. In conclusion, we have developed a novel method for fabrication of AIE active An HPG b CD composites through formation of dynamic phenylboronic borate between b cyclodextrin containing hyperbranched polyglycerol and phenylboronic containing AIE dye. These AIE active composites are of great potential in biological imaging and drug delivery applications.

title: Switchable and adjustable AIE activity of Pt(II) complexes achieving swift responding and highly sensitive oxygen sensing
abstract: AIE active luminogens are attractive for bioimaging, sensors, and optical detections. However, controllably switching and adjusting the AIE activity of luminogens in aqueous media to perform the best of AIE performance under appropriate water fraction remains a challenge. Herein, we report the first case of switchable and adjustable AIE activity based on Pt(II) complexes. The AIE activity of Pt(II) complexes in aqueous media can be flexibly switched and adjusted via finely tuning the rotation activity of the substituents. And the rotation activity of the substituents have been experimentally confirmed by the luminescent lifetimes and theoretically verified by the dipole moments of Pt(II) complexes. Furthermore, luminescent oxygen sensing films were constructed by combining the AIE active Pt(II) complexes with commercially available, low cost ethyl cellulose (EC) With the attenuation of EC film thickness, swift responding quenching/recovering cycles (7.7 s) of the PtTPA EC(N10) oxygen sensing film were demonstrated. And the controllable AIE property of Pt(II) complexes can effectively improve the oxygen sensitivity and the homogeneity of oxygen sensing films.

title: Facile preparation of luminescent cellulose nanocrystals with aggregation induced emission feature through Ce(IV) redox polymerization.
abstract: Cellulose nanocrystals (CNCs) are a novel type of natural nanomaterials that have attracted tremendous research interest for various applications especially in the biomedical fields owing to their natural origin, biodegradable potential, remarkable biocompatibility and massive reactive hydroxyl groups. In this work, a novel strategy has been developed for fabrication of luminescent CNCs with aggregation induced emission (AIE) feature for the first time through a facile one step Ce(IV) redox polymerization for direct surface grafting of AIE dye (PhE) and hydrophilic monomer Poly(ethylene glycol) monomethyl ether acrylate (PEGMA) on CNCs. Various characterization techniques would demonstrate the successful preparation of resultant CNC PhE PEGMA with uniform nanoscale size, remarkable fluorescent properties and extremely low cytotoxicity. Furthermore, compared with conventional modification strategy of CNCs, Ce(IV) redox polymerization only need moderate temperature and can operate in aqueous solution utilizing surface hydroxyl groups of CNCs as polymerization activity sites. More importantly, CNC PhE PEGMA show desirable fluorescent properties and can be used for cell dyeing, indicating their potential for biomedical applications.

title: Self Assembly Fluorescent Cationic Cellulose Nanocomplex via Electrostatic Interaction for the Detection of Fe3+ Ions
abstract: In this work, an aggregation induced emission (AIE) sensor for the detection of Fe3+ ions was fabricated through the electrostatic interaction between 1,1,2 triphenyl 2 [4 (3 sulfonatopropoxyl) phenyl] ethene sodium salt (SPOTPE) and quaternized cellulose (QC) The structure and properties of the SPOTPE/QC nanocomplex were studied by using 1H NMR, spectrofluorophotometer, transmission electron microscopy (TEM) and dynamic laser light scattering (DLS) An aqueous solution of SPOTPE and QC resulted in a remarkably enhanced cyan fluorescence in comparison to that of the SPOTPE solution. Strong through space electrostatic interaction between SPOTPE and QC is the main cause for the fluorescence emerging. The fluorescence of the SPOTPE/QC solutions show good stability over a wide pH range of 5.0 10.0. When introducing Fe3+ ions into the SPOTPE/QC solution, the fluorescence quenched within 5 s. SPOTPE/QC solutions exhibited high selectivity and sensitivity for the detection of Fe3+ ions with ignored interferences from other ions, and the detection limit was determined to be 2.92 x 10 6 M. The quenching mechanism was confirmed to be the consequence of the binding interactions between Fe3+ ions and SPOTPE/QC complex.

title: Fabricating a mechanochromic AIE luminogen into a wearable sensor for volatile organic compound (VOC) detection
abstract: Solid supported sensors and devices benefit greatly from aggregation induced emission (AIE) molecular systems, on account of their high emission efficiency in the aggregated state. In this study, we present an AIE luminogen, (E) 1 (4 acetylphenyl)iminio)methyl)naphthalen 2 olate (AINO) decorated with electron donor acceptor (D A) units. It has strong emission at solid state, but undergoes sharp decrease accompanied by slight hypochromatic shift in response to mechanical stimuli. After fumigation with volatile organic compound (VOC) the emission intensity recovers, showing reversible mechanochromic luminescence. Crystal analysis reveals its working mechanism, which is generally ascribed to the formation of coupled p dimers. Based on the vapochromic recovery of the mechanochromic luminescence; a wearable impregnated cellulose sensor is fabricated, capable of being encapsulated into clothes and gloves. It exhibits remarkable emission change with high visual discrimination when exposed to VOC, affording a low detection down to 17.40 6.91 mg/m3 (4.16 1.77 ppm)

title: Biocompatible organic charge transfer complex nanoparticles based on a semi crystalline cellulose template.
abstract: Using a bio inspired cellulose template, new charge transfer (CT) nanoparticles (NPs) with unique and intriguing emission properties are reported. Pyrene modified 2,3 di O methyl cellulose formed CT complexes with small molecule acceptors, e.g. 7,7,8,8 tetracyanoquinodimethane (TCNQ) and exhibited aggregation induced emission (AIE) in aqueous medium upon nanoparticle formation. The TCNQ CT NPs showed multicolor fluorescence emissions at 370 400 nm, 602 nm and 777 nm, when excited at 330 nm, 485 nm and 620 nm respectively. The cellulose TCNQ NPs are biocompatible and demonstrate an advance in the use of the CT mechanism for biomedical imaging applications both in vitro and in vivo.

title: Aggregation induced emission luminogen@manganese dioxide core shell nanomaterial based paper analytical device for equipment free and visual detection of organophosphorus pesticide.
abstract: Organophosphorus pesticide (OP) residues have gathered considerable attention because of their significant threat to society development and healthy life. Developing a sensitive and practical OPs sensor is highly urgent, whereas remains a huge challenge. To this end, we fabricated a high performance fluorescence paper analytical device (PAD) for apparatus free and visual sensing of OPs based on aggregation induced emission (AIE) luminogen's bright emission in aggregated state, unique response of MnO2 to thiol compounds, and difference of MnO2 and Mn2+ in quenching fluorescence. AIE nanoparticles PTDNPs 0.10 and MnO2 respectively acted as core and shell to prepare PTDNPs@MnO2, which possessed high stability and were dripped on cellulose paper's surface to fabricate AIE PAD. The sensing mechanism is that OPs treated acetylcholinesterase (AChE) prevents the formation of thiocholine, thereby minimizing the reduction of MnO2 into Mn2+ and changing the output signal. As a result, equipment free and visual sensing of OPs was acquired with limit of detection of 1.60 ng/mL. This work justifies the feasibility of applying core shell material to develop high performance sensor and substituting complex/expensive solution phase sensor with PAD, providing a new avenue to bring OPs analysis out of the lab and into the world.