1. |
- Ding, Aixiang, et al.
(author)
-
Complex-Formation-Enhanced Fluorescence Quenching Effect for Efficient Detection of Picric Acid
- 2014
-
In: Chemistry - A European Journal. - : Wiley-VCH Verlag. - 0947-6539 .- 1521-3765. ; 20:38, s. 12215-12222
-
Journal article (peer-reviewed)abstract
- Amine-functionalized alpha-cyanostilbene derivatives (Z)-2-(4-aminophenyl)-3-(4-butoxyphenyl) acrylonitrile (ABA) and (Z)-3-(4-butoxyphenyl)-2-[4-(butylamino) phenyl] acrylonitrile (BBA) were designed for specific recognition of picric acid (PA), an environmental and biological pollutant. The 1:1 host-guest complexes formed between the chemosensors and PA enhanced fluorescence quenching, thus leading to sensitive and selective detection in aqueous media and the solid phase.
|
|
2. |
- Rong, Yu, et al.
(author)
-
Yellow Fluorescent Semiconducting Polymer Dots with High Brightness, Small Size, and Narrow Emission for Biological Applications
- 2014
-
In: ACS Macro Letters. - : American Chemical Society (ACS). - 2161-1653. ; 3:10, s. 1051-1054
-
Journal article (peer-reviewed)abstract
- Cross-linked polymer dots with intense and narrow yellow emission were designed using boron-dipyrromethene (BODIPY) polymer as the acceptor and poly[9,9-dioctylfluorenyl-2,7-diyl-co-1,4-benzo-{2,1-3}-thiadiazole] (PFBT) polymer as the donor. The emission fwhms of the polymer dots (Pdots) were 37 nm. CL-BODIPY 565 Pdots were about S times brighter than commercial quantum dots (Qdots) 565 under identical experimental conditions. Specific cellular targeting indicated that the small, bright, and narrow emissive CL-BODIPY 565 Pdots are promising probes for biological applications.
|
|
3. |
- Zhang, G., et al.
(author)
-
Schiff base modified α-cyanostilbene derivative with aggregation-induced emission enhancement characteristics for Hg2+ detection
- 2014
-
In: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 202, s. 209-216
-
Journal article (peer-reviewed)abstract
- A Schiff base functionalized α-cyanostilbene derivative (TS) has been synthesized via a simple and straightforward method and characterized by FT-IR, 1H NMR, 13C NMR and mass spectra. TS possessed excellent AIEE properties and exhibited turn-on fluorescent responses to Hg2+. The results of UV-vis and fluorescence titration experiments revealed that TS was selective and sensitive to Hg2+ in pure THF and aqueous environment. The coordination of TS and Hg2+ ions generated TS-Hg complex locked the dancing molecule because of the flexible chain in the middle of the molecule and the complex was lower soluble induced formation of large aggregates that further limited the non-radiative relaxation channel enhanced emission after adding Hg2+ ions in aqueous solution, which had been confirmed by 1H NMR and dynamic light scattering (DLS). © 2014 Published by Elsevier Inc.
|
|
4. |
- Hu, Jiwen, et al.
(author)
-
A rhodamine-based fluorescent probe for Hg2+ and its application for biological visualization
- 2014
-
In: Sensors and actuators. B, Chemical. - : Elsevier. - 0925-4005 .- 1873-3077. ; 203, s. 452-458
-
Journal article (peer-reviewed)abstract
- A new visible light excitable fluorescent probe (1) is synthesized by appending a hydroxymethyl-pyridine to rhodamine B hydrazide. The probe displays very specific Hg2+-induced colour change and fluorescent enhancement in the aqueous systems. The "turn-on" response of fluorescence is based on a binding-induced ring-opening process from the spirolactam (nonfluorescent) to acyclic xanthene (fluorescent) in rhodamine B. The coordinating atoms O-center dot-N-N-O-center dot from the hydroxymethyl-pyridine and rhodamine B hydrazide play dominant role in the formation of a complex with 1:1 stoichiometry of Hg2+ to 1. It exhibits a linear response in the range of 0.1-5 mu M with the limit of detection (LOD) of 15.7 nM (3 sigma/slope), while the calculated value of the association constant of Hg2+/1 is 0.70 x 10(5) M-1. Furthermore, confocal microscopy imaging experiment demonstrates the probe 1 can be applied as a fluorescent probe for visualization of Hg2+ in living HeLa cells.
|
|
5. |
- Hu, Zhang-Jun, et al.
(author)
-
A facile "click" reaction to fabricate a FRET-based ratiometric fluorescent Cu2+ probe
- 2014
-
In: Journal of materials chemistry. B. - : Royal Society of Chemistry. - 2050-750X .- 2050-7518. ; 2:28, s. 4467-4472
-
Journal article (peer-reviewed)abstract
- A facile one-step Cu(I)-catalyzed "click" reaction, between a dansyl-azide and a propargyl-substituted rhodamine B hydrazide, is employed to fabricate a novel FRET ratiometric "off-on" fluorescent probe. The sensitive emission of the donor, a dansyl group, overlaps perfectly with the absorption of the acceptor, xanthene in the open-ring rhodamine. The proposed probe shows high selectivity towards Cu2+. The ratio of emission intensities at 568 and 540 nm (I-568/I-540) exhibits a drastic 28-fold enhancement upon addition of Cu2+. The probe shows an excellent linear relationship between emission ratios and the concentrations of Cu2+ from 10 to 50 mu M, with a detection limit (S/N = 3) of 0.12 mu M. The preliminary cellular studies demonstrated that the probe is cell membrane permeable and could be applied for ratiometric fluorescence imaging of intracellular Cu2+ with almost no cytotoxicity. The ingenuity of the probe design is to construct a FRET donor-acceptor interconnector and a selective receptor simultaneously by "click" reaction. The strategy was verified to have great potential for developing novel FRET probes for Cu2+.
|
|
6. |
- Rong, Yu, et al.
(author)
-
Multicolor Fluorescent Semiconducting Polymer Dots with Narrow Emissions and High Brightness
- 2013
-
In: ACS Nano. - : American Chemical Society. - 1936-0851 .- 1936-086X. ; 7:1, s. 376-384
-
Journal article (peer-reviewed)abstract
- Fluorescent semiconducting polymer dots (Pdots) have attracted great interest because of their superior characteristics as fluorescent probes, such as high fluorescence brightness, fast radiative rates, and excellent photostability. However, currently available Pdots generally exhibit broad emission spectra, which significantly limit their usefulness in many biological applications Involving multiplex detections. Here, we describe the design and development of multicolor narrow emissive Pdots based on different boron dipyrromethene (BODIPY) units. BODIPY-containing semiconducting polymers emitting at multiple wavelengths were synthesized and used as precursors for preparing the Pdots, where intraparticle energy transfer led to highly bright, narrow emissions. The emission full width at half-maximum of the resulting Pdots varies from 40 to 55 nm, which is 15-2 times narrower than those of conventional semiconducting polymer dots. BODIPY 520 Pdots were about an order of magnitude brighter than commercial Qdot 525 under identical laser excitation conditions. Fluorescence imaging and flow cytometry experiments indicate that the narrow emissions from these bright Pdots are promising for multiplexed biological detections.
|
|
7. |
- Wang, Guannan, et al.
(author)
-
One-step synthesis of water-dispersible ultra-small Fe3O4 nanoparticles as contrast agents for T-1 and T-2 magnetic resonance imaging
- 2014
-
In: Nanoscale. - : Royal Society of Chemistry. - 2040-3364 .- 2040-3372. ; 6:5, s. 2953-2963
-
Journal article (peer-reviewed)abstract
- Uniform, highly water-dispersible and ultra-small Fe3O4 nanoparticles were synthesized via a modified one-step coprecipitation approach. The prepared Fe3O4 nanoparticles not only show good magnetic properties, long-term stability in a biological environment, but also exhibit good biocompatibility in cell viability and hemolysis assay. Due to the ultra-small sized and highly water-dispersibility, they exhibit excellent relaxivity properties, the 1.7 nm sized Fe3O4 nanoparticles reveal a low r(2)/r(1) ratio of 2.03 (r(1) = 8.20 mM(-1) s(-1), r(2) = 16.67 mM(-1) s(-1)); and the 2.2 nm sized Fe3O4 nanoparticles also appear to have a low r2/r1 ratio of 4.65 (r(1) = 6.15 mM(-1) s(-1), r(2) = 28.62 mM(-1) s(-1)). This demonstrates that the proposed ultra-small Fe3O4 nanoparticles have great potential as a new type of T-1 magnetic resonance imaging contrast agents. Especially, the 2.2 nm sized Fe3O4 nanoparticles, have a competitive r(1) value and r(2) value compared to commercial contrasting agents such as Gd-DTPA (r(1) = 4.8 mM(-1) s(-1)), and SHU-555C (r(2) = 69 mM(-1) s(-1)). In vitro and in vivo imaging experiments, show that the 2.2 nm sized Fe3O4 nanoparticles exhibit great contrast enhancement, long-term circulation, and low toxicity, which enable these ultrasmall sized Fe3O4 nanoparticles to be promising as T-1 and T-2 dual contrast agents in clinical settings.
|
|
8. |
- Ye, F., et al.
(author)
-
Semiconducting polymer dots with monofunctional groups
- 2014
-
In: Chemical Communications. - : Royal Society of Chemistry. - 1359-7345 .- 1364-548X. ; 50:42, s. 5604-5607
-
Journal article (peer-reviewed)abstract
- This communication describes an approach for preparing monovalent semiconducting polymer dots (mPdots) with a size of 5 nm where each mPdot was composed of precisely a single active functional group. © the Partner Organisations 2014.
|
|
9. |
|
|
10. |
- Ballem, Mohamed A., et al.
(author)
-
Low Temperature Nanocasting of Ultrafine Hematite Nanoparticles using Mesoporous Silica Molds
- 2012
-
In: Powder Technology. - : Elsevier. - 0032-5910 .- 1873-328X. ; 217, s. 269-273
-
Journal article (peer-reviewed)abstract
- Iron oxide (α-Fe2O3) nanoparticles with very small size, high crystallinity, and narrow size distribution were synthesized by infiltration of Fe(NO3)3.9H2O as an oxide precursor into mesoporous silica (SBA-15 and SBA-16) molds using a wetimpregnation technique. High resolution transmission electron microscopy shows that during the hydrothermal treatment of the precursor at 140 °C for 2 days, stable α-Fe2O3 nanoparticles inside the silica pores are formed. Subsequent leaching out of the silica template by NaOH resulted in well dispersed nanoparticles with an average diameter of ~ 4 nm.
|
|