制备了一种硫脲分子PNTU探针，基于其对Hg²⁺的专一性比色识别，建立了荧光猝灭法测定Hg²⁺含量的方法。在4-溴-1，8-萘酐的乙醇溶液中，逐滴加入2 mL 80%（质量分数）水合肼溶液，反应完成后，经抽滤，乙醇、水洗涤后干燥，再加入10 mL吡咯烷，在氮气保护下继续反应，得到红褐色固体。将其溶于15 mL乙腈中，室温搅拌下滴加1 mL异硫氰酸苯酯，反应完成后，经减压浓缩、水洗得到PNTU探针。将PNTU探针溶液与体积比为8∶2的乙腈-4-羟乙基哌嗪乙磺酸缓冲液的混合液混匀，然后加入含Hg²⁺的样品溶液，采用荧光猝灭法测定体系的荧光强度。结果显示：当加入Hg²⁺时，体系的荧光强度明显降低，溶液颜色由黄色变成橙红色；干扰试验表明PNTU探针在有其他金属离子存在的情况下仍可检测出Hg²⁺；Hg²⁺浓度在20.0 μmol·L^-1以内与其对应体系的荧光强度降低值呈线性关系，检出限（3S/N）为1.8 nmol·L^-1；对实际水样进行3个浓度水平的加标回收试验，Hg²⁺的回收率为99.6%~104%，测定值的相对标准偏差（n=5）为0.85%~2.6%。基于PNTU探针制备了Hg²⁺的检测试纸，可方便快捷地检测样品中是否存在Hg²⁺。

Based on specific colorimetric recognition of Hg²⁺ with PNTU probe, a method for the determination of Hg²⁺ by fluorescence quenching was established. In the ethanol solution of 4-bromo-1,8-naphthalene anhydride, 2 mL of 80% (mass fraction) hydrazine hydrate solution was added dropwise. After filtering, washing with ethanol and water and drying, pyrrolithane of 10 mL was added. Then reaction was running under the protection of nitrogen to give reddish-brown solid. The reddish-brown solid was dissolved in 15 mL of acetonitrile, and 1 mL of phenyl isothiocyanate was added by stirring at room temperature. After the reaction was completed, the PNTU probe was obtained after vacuum concentration and washing with water. PNTU probe solution was evenly mixed with a mixture of acetonitrile-4-hydroxyethyl piperazine ethanesulfonic acid buffer solution at volume ratio of 8∶2, then Hg²⁺ sample soution was added, and fluorescence intensity of the system was measured by fluorescence quenching. The results showed that the fluorescence intensity of PNTU system decreased obviously when Hg²⁺ was added, following color of the solution changed from yellow to orange-red, and the PNTU probe could detect Hg²⁺ in the presence of other metal ions. Linear relationship between concentration of Hg²⁺ and magnitude of decrease in fluorescence intensity of the system was kept within 20.0 μmol·L^-1, with detection limit (3S/N) of 1.8 nmol·L^-1. Recovery test was made by standard addition method on actual water samples at 3 concentration levels, giving results in the range of 99.6%-104%, and RSDs (n=5) of the determined values ranged from 0.85% to 2.6%. Detection strips based on PNTU probe were prepared, which could easily and quickly detect whether Hg²⁺ exists in the sample.