A new selective fluorescent and colorimetric chemosensor for the detection of GSH was developed. The discrimination of GSH from Cys and Hcy is achieved through two emission channel detection. The detection limit of probe 1 for GSH reached 10 nM (3 ppb). The excellent sensitivity and selectivity of probe 1 allow the selective detection of GSH over Cys and Hcy, which can be visualized colorimetrically and/or fluorescently. The sensitive detection of GSH allowed for convenient measurement of the GSH content in human plasma. The presence of GSH in cells was demonstrated through cell imaging.

A highly selective and sensitive turn-on red fluorescent 1-amino BODIPY-based probe (where BODIPY denotes indole-based boron-dipyrromethene) with high off-to-on contrast ratio has been developed. The probe displayed selective response to thiophenols over aliphatic thiols. Probe 1 is promising for the quantitative detection of thiophenol with a linear response from 6 × 10(-6) M to 1 × 10(-4) M, and the detection limit for thiophenol (PhSH) reaches 4 × 10(-6) M measured in acetonitrile/PBS buffer. The detection limit could be improved to 37 nM (detection limit to 4 ppb) in water when 1% Tween 20 was used to assist the dissolvation of probe 1 in water. Probe 1 is also a useful fluorescent probe for detecting thiophenols in living cells in red emission, which may greatly improve the detectable sensitivity.

A new strategy for the size-controlled preparation of magnetic iron oxide nanocrystals (NCs) within hyperbranched poly(ethylenimine)s (HPEIs) has been described. HPEI was not only utilized as the nanoreactors and stabilizers to prepare size-controlled magnetic NCs, but also skillfully used as a base supplier to avoid introducing alkali hydroxide or ammonia. By changing the weight ratio of FeSO 4 $7H 2 O to HPEI, magnetic iron oxide NCs with various sizes were obtained. Owing to the efficient gene transfection properties of HPEI, the resulting iron oxide/HPEI nanocomposites were used as magnetic nonviral gene vectors for magnetofection and showed to be good gene vectors. It was found that the size of magnetic iron oxide had a significant effect on the magnetofection properties while a pure HPEI transfection enhancer was not introduced. When the mean size of magnetic iron oxide increased, the transfection efficiency was enhanced. With the addition of a pure HPEI transfection enhancer, the size of magnetic iron oxide showed a slight impact on the magnetofection properties. The luciferase expression levels mediated by iron oxide/HPEI nanocomposites with various iron oxide sizes in COS-7 cells under a magnetic gradient field were all more than 115 fold of that of standard HPEI transfection.

A novel turn-on fluorescent 8-amino BODIPY-based probe carrying a thiourea unit as the mercury ion recognition unit has been developed. Due to the cascade reaction processes, consecutive color changes reflecting the electronic absorption and emission responses were observed upon addition of increased concentrations of mercury(ii) ions. The likely sensing mechanism was proposed as mercury ion-promoted cyclization and subsequent hydrolysis. The probe displayed a selective response to mercury ions over other metal ions. Additionally, experiments with living Human Hepatoma SMMC-7721 cells to visualize intracellular mercury ions in biological systems were carried out with the probe.

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Acylhydrazone based extended dipyrrins L1-H and L2-H are introduced as complexometric ppb sensitive metal ion detectors. The binding of lanthanide, transition as well as post-transition metal ions is followed by UV-Vis measurements. The carbohydrate based ligand L2 is water soluble and thus can act as a metal ion sensor in this medium.