No abstract

Despite their status of being widely used as food additives, bisulfite (HSO 3 − )/sulfite (SO 3 2− ) can pose serious health risks when they are excessively added. Therefore, it is vital to develop a new method for detecting HSO 3 − /SO 3 2− in foodstuff. In this paper, a benzopyran-benzothiazole derivative (probe DCA−Btl) with near-infrared emission was designed and synthesized by constructing a "push-pull" electronic system. DCA−Btl can selectively recognize HSO 3 − /SO 3 2− via a colorimetric and fluorescence dual channel in DMF/PBS (1:1, v/v, pH = 8.4), and the emission wavelength of DCA−Btl can reach 710 nm. The fluorescence quenching of DCA−Btl after recognition of HSO 3 − is attributed to the photoinduced electron transfer (PET) process of the adduct DCA−Btl-HSO 3 − as evaluated by the DFT/TD-DFT method. In addition, DCA−Btl has many advantages, including a large Stokes shift (95 nm), good anti-interference ability, and little cytotoxicity. What's more, DCA−Btl has been successfully applied for the detection of HSO 3 − /SO 3 2− in actual water samples and food samples such as sugar, red wine, and biscuits with satisfying results, as well as for fluorescent imaging of HSO 3 − in living MCF-7 cells.

Pyn, 该化合物在 MeCN/磷酸缓冲容 溶液(PBS) (V∶V＝2∶8, PBS 2×10 -2 mol/L, pH＝7.4)混合溶液中能高选择性荧光"OFF-ON"识别 Pd 2＋ , 发射波长达 到近红外区(653 nm). 该探针具有较好的抗干扰能力、较宽的 pH 适用范围(3～8)和较低的检测限(6.92 μmol/L). 应用研 究表明, TCF-Pyn 能检测真实水样中的 Pd 2＋ , 并可对活细胞中的 Pd 2＋ 进行荧光成像.