Department of Chemistry, Hong Kong Baptist University, 224 Waterloo Road, Kowloon Tong, Hong Kong SAR, People's Republic of China.
Nanoscale. 2012 Sep 7;4(17):5325-32. doi: 10.1039/c2nr30984j. Epub 2012 Jul 9.
Reverse-phase high-performance liquid chromatographic (RP-HPLC) separation and analysis of polydisperse water-soluble gold nanoclusters (AuNCs) stabilised with N,N'-dimethylformamide (DMF) were investigated. Under optimal elution gradient conditions, the separation of DMF-AuNCs was monitored by absorption and fluorescence spectroscopy. The UV-vis spectral characteristics of the separated DMF-AuNCs have been captured and they do not possess distinct surface plasmon resonance bands, indicating that all DMF-AuNCs are small AuNCs. The photoluminescence emission spectra of the separated DMF-AuNCs are in the blue-light region. Moreover, cationic DMF-AuNCs are for the first time identified by ion chromatography. Our proposed RP-HPLC methodology has been successfully applied to separate AuNCs of various Au atoms as well as DMF-stabilised ligands. Finally, the composition of the separated DMF-AuNCs was confirmed by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry and electrospray ionisation mass spectrometry, proving that the as-synthesised DMF-AuNCs product consists of Au₁₀⁺, Au₁₀, Au₁₁, Au₁₂, Au₁₃, and Au₁₄ NCs stabilised with various numbers of DMF ligands.
采用反相高效液相色谱（RP-HPLC）对 N,N'-二甲基甲酰胺（DMF）稳定的多分散水溶性金纳米簇（AuNCs）进行分离和分析。在最佳洗脱梯度条件下，通过吸收和荧光光谱监测 DMF-AuNCs 的分离情况。分离出的 DMF-AuNCs 的紫外可见光谱特征已被捕获，它们不具有明显的表面等离子体共振带，表明所有 DMF-AuNCs 都是小的 AuNCs。分离出的 DMF-AuNCs 的荧光发射光谱位于蓝光区域。此外，首次通过离子色谱鉴定出带正电荷的 DMF-AuNCs。我们提出的 RP-HPLC 方法已成功用于分离具有不同金原子数的 AuNCs 以及 DMF 稳定配体。最后，通过基质辅助激光解吸/电离飞行时间质谱和电喷雾电离质谱确认分离出的 DMF-AuNCs 的组成，证明所合成的 DMF-AuNCs 产物由各种 DMF 配体稳定的 Au₁₀⁺、Au₁₀、Au₁₁、Au₁₂、Au₁₃ 和 Au₁₄ NCs 组成。
