Size-tunable Au@Ag nanoparticles for colorimetric and SERS dual-mode sensing of palmatine in traditional Chinese medicine

Publication date: Available online 22 May 2019Source: Journal of Pharmaceutical and Biomedical AnalysisAuthor(s): Yaohui Gao, Ziwei Hu, Jiamin Wu, Zan Ning, Jingyi Jian, Ting Zhao, Xiaochen Liang, Xingjie Yang, Zi Yang, Qinyu Zhao, Jianping Wang, Zhigang Wang, Nicoleta Elena Dina, Ana Maria Raluca Gherman, Zhengjin Jiang, Haibo ZhouAbstractPalmatine is a protoberberine alkaloid separated from several plants and application as an anti-inflammatory and antibacterial agent in the therapy of gastrointestinal and genitourinary disorder. Thus, the fast quantification of palmatine is important in clinic medical assays. Herein, we report simple, fast and sensitive colorimetric visualization and surface-enhanced Raman spectroscopy (SERS) dual-mode detection of palmatine basing on bimetallic size tunable silver shell capped gold nanoparticles (Au@Ag NPs). Interesting, the best signals output for dual-mode sensing of palmatine were both 5 nm Ag shell thickness of Au@Ag NPs. Meanwhile, we found that the addition of NaHSO4 significantly improves the aggregating sensitivity of Au@Ag NPs to trace palmatine. Upon exposure to 0.1 μM level palmatine, NaHSO4-optimized Au@Ag NPs solution exhibits a highly sensitive color change from orange to green and rapid aggregation kinetics within the initial 5 min, which can directly be seen with the naked eye and monitored by UV-vis absorbance spectra. In addition, we measured palmatine by SERS with the excellent enhancement effect of Au@Ag NPs for...
Source: Journal of Pharmaceutical and Biomedical Analysis - Category: Drugs & Pharmacology Source Type: research