A new class of aggregation-induced emission (AIE) compounds with strong blue-light-emitting properties and a high thermal stability, derived from triphenylethylene carbazole, has been synthesized. Their glass transition temperatures range from 126-151 C and the maximum fluorescence emission wavelengths are 451-466 nm.

The important roles of biothiols in biological systems have attracted great interest in the determination of biothiols. Although great progress has been made in fluorescent biothiol probes, near-infrared (NIR) fluorescent probes for biothiols are rather few even such NIR probes can avoid interference from biological media such as tissue autofluorescence and scattering light, and thereby facilitate relatively interference-free sensing. Herein, we report photoactivated CdTe/CdSe quantum dots (QDs) as a novel NIR fluorescent probe for biothiols. The photoactivated CdTe/CdSe QDs based NIR fluorescent probe offers good sensitivity and selectivity for detecting cysteine (Cys), homocysteine (Hcy), and glutathione (GSH) in the presence of 20 other amino acids, main relevant metal ions, and some other molecules in biological fluids. The recovery of spiked 5.0 microM thiols in human urine, plasma, and cell extracts ranges from 90% to 109%. The precision for nine replicate measurements of the thiols at 5.0 microM is in the range from 1.6% to 1.8%. The detection limits for Cys, Hcy, and GSH are 131, 26, and 20 nM, respectively. This assay is based on both the superior photoactivity of CdTe/CdSe QDs and the strong affinity of thiols to photoactivated CdTe/CdSe QDs. The addition of thiols into the photoactivated CdTe/CdSe QDs improves the passivation of the illumination-induced traps, meanwhile reduces most of Se(IV) and Te(IV) on the surface of photoactivated CdTe/CdSe QDs so as to improve the fluorescence property.

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Folate receptor (FR) can be overexpressed by a number of epithelial-derived tumors, but minimally expressed in normal tissues. As folic acid (FA) is a high-affinity ligand to FR, and not produced endogenously, development of FA-conjugated probes for targeted imaging FR overexpressed cancer cells is of significance for assessing cancer therapeutics and for better understanding the expression profile of FR in cancer. Here we report a novel turn-on fluorescence probe for imaging FR overexpressed cancer cells. The probe was easily fabricated via electrostatic self-assembly of FA and polyethyleneimine-coated CdS/ZnS quantum dots (PEI-CdS/ZnS QDs). The primary fluorescence of PEI-CdS/ZnS QDs turned off first upon the electrostatic adsorption of FA onto PEI-CdS/ZnS QDs based on electron transfer to produce negligible fluorescence background. The presence of FR expressed on the surface of cancer cells then made FA desorb from PEI-CdS/ZnS QDs due to specific and high affinity of FA to FR. As a result, the primary fluorescence of PEI-CdS/ZnS QDs adhering to the cells turned on due to the inhibition of electron transfer. The most important merits of the developed probe are its simplicity and the effective avoidance of the false positive results due to the simple electrostatic self-assembly of FA onto the surface of PEI-CdS/ZnS QDs and the involved fluorescence "off-on" mechanism. The probe was demonstrated to be sensitive and selective for targeted imaging of FR overexpressed cancer cells in turn-on mode.

This work develops an integrated microcapillary-based loop-mediated isothermal amplification (icLAMP) containing preloaded reagents and DNA extraction card, allowing for sample-to-answer screening of single nucleotide polymorphisms (SNPs) typing of the CYP2C19 gene from untreated blood samples with minimal user operation. With all reagents and the DNA extraction card preloaded inside the capillary, this icLAMP system can achieve on-site pretreatment, extraction, amplification, and detection of nucleic acids within 150 min, without the requirement for advanced instruments. As icLAMP technology carries many advantages such as disposability, easy operation, low cost, and reduced cross contamination and biohazard risks, we expect this system to have a great impact on point-of-care (POC) nucleic acid detection.

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Type‐II CdTe/CdSe quantum dots are synthesized by an aqueous method of layer‐by‐layer epitaxial growth. The QDs are 4–5 nm in diameter witha fluorescence quantum yield up to 12% in the near‐infrared region (NIR; see image). They match the demands for the probes of NIR in vivo imaging and are applied in fixed Hela cells imaging.