New ß-diketone-boron difluoride based near-infrared fluorescent probes for polarity detection.

Two new ß-diketone-boron difluoride based near-infrared fluorescent probes 1 and 2 which exhibit polarity sensitivity have been designed and synthesized. Probes 1 and 2 are composed of a ß-diketone-boron difluoride moiety as an acceptor unit, and a diethylamino group and a phenolic hydroxyl group as donor units. The long conjugate structures form a "donor-acceptor-donor" configuration, induce intramolecular charge transfer (ICT), and confer near-infrared fluorescence emission and excellent polarity sensitivity. The photophysical properties of these two probes were investigated in detail. Experimental data demonstrated that as the environmental polarity decreased, the fluorescence intensity of the probes increased obviously, accompanied by a blue-shift of the maximum emission wavelength. In addition, these two probes were photostable and solely sensitive to polarity without interference from viscosity, pH and common active species. Theoretical calculations indicated that probes 1 and 2 displayed lower energy gaps and faster non-radiative decay in polar solvents. Furthermore, probes 1 and 2 were utilized to quantitatively detect the polarity of a binary mixture through the satisfactory linear relationship between the fluorescence emission intensity ratios and the orientation polarizability of the mixed solvent. Additionally, probe 1 was successfully utilized to visualize the polarity distribution of live cells. Both of these probes are perfect candidates for studying polarity in vitro and even in live systems.

An ultrasensitive sandwich-type electrochemical immunosensor based on the signal amplification system of double-deck gold film and thionine unite with platinum nanowire inlaid globular SBA-15 microsphere.

A novel thionine unites with platinum nanowire inlaid globular SBA-15 (Pt NWs@g-SBA-15/Thi) not only utilizes as an efficient electrical signal probe but also constitutes an amplifying system with double-deck gold film (D-Au film) have been applied to the fabrication of sandwich-type immunosensor for detecting hepatitis B surface antigen (HBs Ag). The D-Au film can accelerate the electron transfer on the electrode interface due to the tunneling effect between the two Au films and can improve the load capacity of primary antibodies (Ab1) because of the good biocompatibility. The Pt NWs@g-SBA-15/Thi with uniform globular morphology not only can effectively reduce the spatial limitation for loading the secondary antibodies (Ab2) but also can provide outstanding pore accessibility of guest species from outside and offer catalytically active sites in a large scale. Besides, the presence of Thi can well enhance the electrical conductivity of Pt NWs@g-SBA-15/Thi. With the good cooperation between D-Au film and Pt NWs@g-SBA-15/Thi, a linear relationship between current signals and the concentrations of HBs Ag was obtained in the wide range from 10 fg/mL to 100ng/mL and the detection limit of HBs Ag was 3.3 fg/mL (signal-to-noise ratio of 3). Furthermore, the designed immunosensor with excellent selectivity, reproducibility and stability shows excellent performance in detection of human serum samples and provides a promising capacity for detecting a wide range of other tumor markers in clinical application.

An ultrasensitive sandwich-type electrochemical immunosensor based on the signal amplification strategy of mesoporous core-shell Pd@Pt nanoparticles/amino group functionalized graphene nanocomposite.

Herein, a novel and sensitive sandwich-type electrochemical immunosensor was fabricated for quantitative monitoring of prostate specific antigen (PSA). The sulfo group functionalized multi-walled carbon nanotubes (MWCNTs-SO3H) were used as substrate material to increase the specific surface area and enhance the conductivity of the glassy carbon electrode. Gold nanoparticles (Au NPs) were introduced to enhance the load capacity of the substrate material for primary antibodies (Ab1) and accelerate the electron transfer on the electrode interface. The mesoporous core-shell Pd@Pt nanoparticle loaded by amino group functionalized graphene (M-Pd@Pt/NH2-GS) with high specific surface area, high indexed facets, and good biocompatibility was not only as the carriers of secondary antibodies (Ab2) but also catalyzed the reduction of hydrogen peroxide (H2O2), which effectually amplified the current signal in detection of PSA. The as-proposed immunosensor exhibited high sensitivity and stability on the detection of PSA. A linear relationship between current signals and the concentrations of PSA was obtained in the range from 10fg/mL to 50ng/mL and the detection limit of PSA was 3.3fg/mL (signal-to-noise ratio of 3). Furthermore, the as-proposed immunosensor showed excellent performance in detection of human serum samples. The results suggest that the proposed immunosensor will be promising in the diagnostics application for accurately quantitative detection of PSA.

5-(3-Fluoro-phen-yl)-1-phenyl-pyrazolidin-3-one.

In the mol-ecule of the title compound, C(15)H(13)FN(2)O, the phenyl and fluorophenyl rings are oriented at a dihedral angle of 77.92 (3)°. The pyrazolidine ring adopts an envelope conformation. An intra-molecular C-H⋯N hydrogen bond results in the formation of a five-membered ring adopting an envelope conformation. In the crystal structure, inter-molecular N-H⋯O and C-H⋯O hydrogen bonds link the mol-ecules. There are C-H⋯π contacts between between aromatic H atoms and the phenyl and fluorophenyl rings. A π-π contact between phenyl rings [centroid-centroid distance = 3.926 (1) Å] is also observed.

2,3,4,6-Tetra-O-acetyl-1-O-(4-methoxy-cinnamo-yl)-ß-d-glucopyran-ose.

Mol-ecules of the title compound, C(24)H(28)O(12), are linked by inter-molecular C-H⋯O hydrogen bonds. Bond lengths and angles are normal.

(S)-(-)-Methyl 2-(p-tolyl-sulfon-yloxy)-propanoate.

In the title compound, C(11)H(14)O(5)S, there is an intra-molecular C-H⋯O hydrogen bond, for which the C-C-S-O torsion angle involving the acceptor and donor atoms is 2.4 (4)°. The dihedral angle between the benzene ring and the methoxy-carbonyl plane is 52.7 (4)°. In the crystal structure, mol-ecules are linked via inter-molecular C-H⋯O hydrogen bonds, forming a mol-ecular chain along the b axis.

2-[Bis(3,5-dimethyl-phen-yl)-phosphor-yl]-propan-2-ol hemihydrate.

In the organic mol-ecule of the title compound, C(19)H(25)O(2)P·0.5H(2)O, the benzene rings are oriented at a dihedral angle of 54.04 (3)°. Intra-molecular C-H⋯O hydrogen bonds result in the formation of two five-membered planar rings, which are oriented with respect to the adjacent benzene rings at dihedral angles of 2.66 (3) and 2.79 (3)°. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules. The water oxygen atom lies on a twofold rotation axis.

1-Phenyl-5-[4-(trifluoro-meth-yl)phen-yl]-pyrazolidin-3-one monohydrate.

In the mol-ecule of the title compound, C(16)H(13)F(3)N(2)O·H(2)O, the two benzene rings are oriented at a dihedral angle of 82.55 (3)° and the pyrazole ring adopts an envelope conformation. In the crystal structure, inter-molecular C-H⋯F hydrogen bonds link the mol-ecules into chains.

3,7-Dihydr-oxy-3,7-diphenyl-2H,6H-pyrrolo[3,4-f]isoindole-1,5(3H,7H)-dione methanol disolvate.

The asymmetric unit of the title compound, C(22)H(16)N(2)O(4)·2CH(4)O, contains one half-mol-ecule and a methanol solvent mol-ecule. The aromatic ring is oriented at a dihedral angle of 82.91 (3)° with respect to the planar indole ring systems. In the crystal structure, inter-molecular O-H⋯O and N-H⋯O hydrogen bonds link the mol-ecules into chains along the b axis.