Gao Dangge, Zhang Ailin, Lyu Bin, Ma Jianzhong
College of Bioresources Chemical and Materials Engineering, Shaanxi University of Science & Technology, Xi'an, 710021, Shaanxi, China.
National Demonstration Center for Experimental Light Chemistry Engineering Education, Shaanxi University of Science & Technology, Xi'an, 710021, Shaanxi, China.
Mikrochim Acta. 2024 Mar 26;191(4):219. doi: 10.1007/s00604-024-06251-1.
Hydroxypropyl chitosan-CsBiCl perovskite quantum dots (HPCS-PQDs) were synthesized by a simple ligand-assisted reprecipitation method via green hydroxypropyl chitosan as the ligand and used as the specific signal of a fluorescence probe to achieve the highly sensitive detection of hexavalent chromium (Cr(VI)) and compared with chitosan-CsBiCl QDs (CS-PQDs). HPCS-PQDs with multiple active hydroxyl passivations were found to enhance the photoluminescence quantum yield (PLQY) by 90%. After being placed in aqueous solution and irradiated with ultraviolet light for 96 h the fluorescence intensity of HPCS-PQDs remained above 60%. The blue emission of HPCS-PQDs has a good selectivity and short response time (30 s) for Cr(VI). A good linear relationship is established between the fluorescence quenching rate of the HPCS-PQDs and concentration of Cr(VI) from 0.8 to 400 µM, with a limit of detection (LOD) of 0.27 µM. The fluorescence quenching mechanism is the static quenching and internal filtration effect caused by HPCS-PQDs forming a non-fluorescent ground-state complex with Cr(VI). The sensor can not only be used to detect Cr(VI) in water samples with high accuracy but can also be prepared as a test paper for the detection for Cr(VI).
通过简单的配体辅助再沉淀法，以绿色的羟丙基壳聚糖为配体合成了羟丙基壳聚糖-CsBiCl钙钛矿量子点（HPCS-PQDs），并将其用作荧光探针的特异性信号，以实现对六价铬（Cr(VI)）的高灵敏度检测，并与壳聚糖-CsBiCl量子点（CS-PQDs）进行了比较。发现具有多个活性羟基钝化的HPCS-PQDs可将光致发光量子产率（PLQY）提高90%。将HPCS-PQDs置于水溶液中并用紫外光照射96小时后，其荧光强度仍保持在60%以上。HPCS-PQDs的蓝色发射对Cr(VI)具有良好的选择性和较短的响应时间（30秒）。HPCS-PQDs的荧光猝灭速率与Cr(VI)浓度在0.8至400μM之间建立了良好的线性关系，检测限（LOD）为0.27μM。荧光猝灭机制是HPCS-PQDs与Cr(VI)形成非荧光基态络合物引起的静态猝灭和内滤效应。该传感器不仅可以高精度地检测水样中的Cr(VI)，还可以制备成用于检测Cr(VI)的试纸。
