Polymer dots possess superior emissive features, but most of them give rise to luminescence bands in the blue region. In addition, blue or green emissions have difficulty in penetrating tissue deeply. Therefore, long wavelength emissive signals are welcome for the development and application of polymeric dots towards sensing and bio-analysis. Herein, the color-tunable fluorescence polymer nanoparticles (F-PNPs) have been synthesized via one-step strategy based on the employment of hydroquinone and polyethyleneimine as precursors at low temperature. Moreover, its emission peak can be shifted from 523 nm to 612 nm by varying the excitation wavelength in the range of 380 nm to 480 nm. In view of sensing assessment, F-PNPs enable the quantitative determination of trace amount of SO₃^2- and Cu²⁺. In the presence of SO₃^2-, the polymer dots exhibit ratiometric fluorescence signals in deionized water and the color change from green to blue has been clearly observed by naked eyes (detection limit = 59 nM). In addition, two emission bands at 545 nm (green) and 601 nm (red) are observed to be responsive to the exposure of Cu²⁺. The entire dual sensing system for the detection of Cu²⁺ will be more accurate and reliable. The evaluation results reveal their optical signals are improved linearly due to the addition of Cu²⁺ at increasing concentrations and the detection limits are calculated to be 76 nM (green) and 41 nM (red), respectively. Such polymeric network will provide a new dynamic platform for sensing purposes in biomedicine study, environmental protection, and food safety.

聚合物点具有出色的发射特性，但大多数都在蓝色区域产生发光带。另外，蓝色或绿色发射难以深入穿透组织。因此，对于聚合物点在传感和生物分析方面的开发和应用，欢迎使用长波长发射信号。本文中，基于在低温下使用对苯二酚和聚乙烯亚胺作为前体，通过一步策略合成了颜色可调荧光聚合物纳米颗粒（F-PNP）。此外，通过在380 nm至480 nm范围内改变激发波长，可以将其发射峰从523 nm移至612 nm。鉴于传感评估，F-PNP可定量测定痕量的SO ₃ ^2-和Cu²⁺。在SO ₃ ^2-的存在下，聚合物点在去离子水中显示出成比例的荧光信号，并且用肉眼清楚地观察到了从绿色到蓝色的颜色变化（检测限= 59 nM）。此外，观察到在545 nm（绿色）和601 nm（红色）的两个发射带对Cu ²⁺的暴露有响应。用于检测Cu ²⁺的整个双传感系统将更加准确和可靠。评估结果表明，由于添加了Cu ^2+，其光信号线性改善浓度增加时，检测限分别为76 nM（绿色）和41 nM（红色）。这样的聚合物网络将为生物医学研究，环境保护和食品安全中的传感目的提供一个新的动态平台。