硫杂杯[4]荧光探针的离子识别及分子逻辑门研究

以硫杂杯4]芳烃为母体,在其1,3-位连接羟乙基邻苯二甲酰亚胺,2,4-位以三氮唑为连接基,将苄基引入硫杂杯4]芳烃的下沿,得到硫杂杯4]-邻苯二甲酰亚胺衍生物荧光探针(s1)。探针s1发射强烈荧光,在CH_3CN介质中的相对荧光量子产率为0.43。在DMF/H_2O介质中,以310nm为激发波长,Fe~(3+)能选择性猝灭探针s1在390nm处的荧光;在CH_3CN介质中,以245nm为激发波长,I~-能选择性猝灭探针s1在310nm处的荧光,光谱滴定和等温滴定量热均测出探针s1与Fe~(3+)或与I~-形成1∶1配合物,结合常数均达105。结合自由能表明配合为自发过程。荧光猝灭检测Fe~(3+)和I~-的浓度线性范围分别为1.0×10~(-7)~1.6×10~(-4) mol·L~(-1)和1.0×10~(-7)~8.5×10~(-5) mol·L~(-1),检测限分别为2.30×10~(-8) mol·L~(-1)和1.17×10~(-8) mol·L~(-1)。同时,利用识别和竞争配合作用,控制Fe~(3+)和F~-的输入使探针s1发射荧光或荧光猝灭,构建了分子水平上的逻辑电路。红外光谱推测探针s1分子中三氮唑基的氮原子参与了识别Fe~(3+)的配位,而探针s1分子中三氮唑环上的芳氢与I~-形成氢键而实现识别。

The Ion Identification and Molecular Logic Gate of a Thiacalix [4 ]arene Fluorescent Probe

A disubstituted phthalimide‐based thiacalix4] arene derivative (probe s1) was synthesized from cone 1 ,3‐thiacalix4] arene and hydroxyethyl phthalimide ,with benzyl appended the lower edge of thiacalix 4]‐arene by triazole ring in the 2 ,4 posi‐tion .The relative fluorescence quantum yield of probe s1 is 0.43 in CH3CN solvent .The strong fluorescence emission of probe s1 at 390 nm wavelength can be selectively quenched by Fe3+ in DMF/H2O solution .Similarly ,the presence of I- also induced a significant fluorescence quenching of probe s1 at 310 nm wavelength in CH3 CN solution .Spectral titration and isothermal titra‐tion calorimetry were showed that probe s1 with Fe3+ or I- both form 1∶1 complexes ,the binding constants up to 105 and coor‐dinate process were spontaneous .The linear ranges of fluorescence detect Fe3+ or I- were 1.0 × 10-7 ~1.6 × 10-4 mol?L -1 and 1.0 × 10-7 ~8.5 × 10-5 mol?L -1 ,detection limits were up to 2.30 × 10-8 mol?L -1 and 1.17 × 10-8 mol?L -1 ,respectively . Meanwhile ,take advantage of identification and coordination action ,a logic circuit constructed at the molecular level by control‐ling two input signals of Fe3+ and F- ,which causing probe s1 cycling of fluorescence emission or quenching .IR spectrum specu‐lated that the nitrogen atoms of triazole groups are involved in the complexation with Fe 3+ ,while the hydrogen atoms of triazole groups were complexed with I - by hydrogen bonding .