化学学报 ›› 2016, Vol. 74 ›› Issue (11): 929-934.DOI: 10.6023/A16080427 上一篇    下一篇

研究论文

基于聚集诱导发光金纳米簇构筑发光超薄膜

管伟江, 周文娟, 吕超   

  1. 化工资源有效利用国家重点实验室 北京化工大学 北京 100029
  • 收稿日期:2016-08-24 出版日期:2016-11-15 发布日期:2016-10-20
  • 通讯作者: 吕超 E-mail:luchao@mail.buct.edu.cn
  • 基金资助:

    项目受国家重点基础研究发展计划(973项目,No.2014CB932103)、国家自然科学基金(Nos.21575010,21375006)资助.

Ultrathin Luminescence Film Based on Gold Nanoclusters with Aggregation-Induced Emission

Guan Weijiang, Zhou Wenjuan, Lü Chao   

  1. State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029
  • Received:2016-08-24 Online:2016-11-15 Published:2016-10-20
  • Supported by:

    Project supported by the National Basic Research Program of China (973 Program, No. 2014CB932103), and the National Natural Science Foundation of China (Nos. 21575010 and 21375006).

选用带负电的谷胱甘肽包裹的金纳米簇(GSH-AuNCs)和牛血清白蛋白包裹的金纳米簇(BSA-AuNCs),与带正电荷的聚烯丙胺(PAH)通过静电作用以层层组装的方式制备了发黄色荧光的GSH-AuNCs/PAH薄膜和发红色荧光的BSA-AuNCs/PAH薄膜.在保证荧光强度的前提下,采用具有聚集诱导发光(AIE)效应的GSH-AuNCs能够大幅度降低薄膜厚度,有利于提高传感薄膜的响应速度和灵敏度.据此,以BSA-AuNCs/PAH薄膜作为参比层,GSH-AuNCs/PAH薄膜作为响应层,设计并构建了一种新型的比率荧光复合薄膜传感体系,并以2,4,6-三硝基甲苯(TNT)为例对其传感特性进行了研究.

关键词: 金纳米簇, 聚集诱导发光, 发光薄膜, 层层组装, 爆炸物

Solution-based fluorescent probes usually need to be fabricated into fluorescent films for device application. The fabricated fluorescent films can have not only the original advantages of probes (e.g., high sensitivity and selectivity) but also several unique properties, such as tunable shape and size, recycling, non-invasion, good stability and portability, and real-time detection. However, the sensitivity of fluorescent films is often reduced by the aggregation-caused quenching (ACQ) effect during the film formation:fluorophores with high concentration inherently tend to aggregate through intermolecular π-π in-teractions. Moreover, the sensing performances of the fluorescent film are significantly influenced by the diffusion rate of analytes:the thicker the films, the slower the response time towards target molecules. Therefore, aggregation-induced emission (AIE) materials are urgently needed to be developed to overcome these shortcomings. On the other hand, excellent photostability could be better for the practical applications in the integrated sensor devices. However, most of the present AIEgens are π-conjugated organic molecules with poor ability against photobleaching. Interestingly, several fluorescent gold nanoclusters (AuNCs) with higher photostability were discovered to have AIE property. In this work, two kinds of negatively-charged fluorescent AuNCs were selected:bovine serum albumin capped AuNCs (BSA-AuNCs) and AIE-active glutathione capped AuNCs (GSH-AuNCs). Quartz glass slides were alternately dipped into a poly(allylamine) (PAH) solution and AuNCs solutions to fabricate GSH-AuNCs/PAH (yellow-emitting) and BSA-AuNCs/PAH (red-emitting) fluorescent ultrathin films, respectively. As expected, the photoluminescence quantum yield of GSH-AuNCs is two-fold higher in GSH-AuNCs/PAH ultrathin films than in solution. The fluorescence of (GSH-AuNCs/PAH)5 ultrathin film could be quenched effectively by 2,4,6-trinitrotoluene (TNT) in 10 min, while the fluorescence intensity of (BSA-AuNCs/PAH)25 ultrathin film remain almost unchanged. Based on this phenomenon, a novel ratio fluorescence sensing system was constructed by using (BSA-AuNCs/PAH)25 ultrathin film as control and (GSH-AuNCs/PAH)5 ultrathin film as the detection unit. The fluorescence intensity ratios (I565/I620) have a linear relationship with the log concentrations of TNT in the range of 10-6~10-9 mol/L with detection limit of 1.0×10-10 mol/L.

Key words: gold nanocluster, aggregation-induced emission, luminescent film, layer-by-layer assembly, explosive