College of Chemistry and Materials Science, Anhui Key Laboratory of Chemo/Biosensing, The Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-based Materials, Anhui Normal University, Wuhu, 241000, Anhui, China.
School of Pharmaceutical Sciences, Gannan Medical University, Ganzhou, 341000, Jiangxi, China.
Anal Bioanal Chem. 2020 Feb;412(5):1235-1242. doi: 10.1007/s00216-019-02360-6. Epub 2020 Jan 6.
Water-soluble nonconjugated fluorescent polymer nanoparticles (NFPNs) were prepared from branched polyethylenimine (PEI) and citric acid through an amide condensation reaction in the aqueous phase. The NFPNs were characterized using a transmission electron microscope, Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectra (XPS). The NFPN fluorescence (with excitation/emission peaks at 360/450 nm) was quenched by 2,4,6-trinitrophenol (TNP) at trace concentrations through the inner filter effect and the formation of self-assembled non-fluorescent Meisenheimer complexes of TNP on the NFPN surfaces through acid-base interactions. The complexes effectively enriched TNP from the bulk solution on the NFPN surfaces through acid-base interactions, and the strong overlap between NFPN excitation and TNP absorption peaks contributed to NFPNs having good sensitivity and selectivity for TNP. The method was selective for TNP and was not sensitive to other interfering species. The calibration plot of log(F/F) versus TNP concentration shows a linear relationship (R = 0.999) for TNP concentration in the range of 0.5-150 μM. The detection limit for TNP was 0.7 μM. The assay was successfully used to determine TNP in spiked lake water samples, and the recoveries were 96.6-102.7%.
水溶性非共轭荧光聚合物纳米粒子（NFPNs）是通过支化聚乙烯亚胺（PEI）和柠檬酸在水相中通过酰胺缩合反应制备的。使用透射电子显微镜、傅里叶变换红外（FTIR）光谱和 X 射线光电子能谱（XPS）对 NFPN 进行了表征。NFPN 荧光（激发/发射峰在 360/450nm）在痕量浓度下被 2,4,6-三硝基苯酚（TNP）通过内滤效应猝灭，并通过酸碱相互作用在 NFPN 表面上形成 TNP 的自组装非荧光 Meisenheimer 配合物。这些配合物通过酸碱相互作用有效地将 TNP 从本体溶液中富集到 NFPN 表面上，并且 NFPN 激发和 TNP 吸收峰之间的强烈重叠使得 NFPN 对 TNP 具有良好的灵敏度和选择性。该方法对 TNP 具有选择性，对其他干扰物质不敏感。NFPN 浓度的 log(F/F)与 TNP 浓度的校准曲线在 0.5-150μM 的范围内呈线性关系（R=0.999）。TNP 的检测限为 0.7μM。该测定法成功地用于测定加标湖水样品中的 TNP，回收率为 96.6-102.7%。
