García-Ruiz Carmen, Scholtes Maarten J, Ariese Freek, Gooijer Cees
Department of Analytical Chemistry and Applied Spectroscopy, Laser Centre, Vrije Universiteit, De Boelelaan 1083, NL-1081 HV Amsterdam, The Netherlands.
Talanta. 2005 Apr 30;66(3):641-5. doi: 10.1016/j.talanta.2004.12.010. Epub 2005 Jan 6.
Inclusion complexes between camphorquinone (CQ) and cyclodextrins (CDs) in deoxygenated aqueous solutions are shown to exhibit relatively strong room temperature phosphorescence (RTP). Among the various CDs tested, alpha-CD showed the strongest RTP signals. Interestingly, these signals differed significantly for the two enantiomers of CQ; the phosphorescence lifetime of (+)-CQ was about four times longer than that of (-)-CQ, being 352+/-16 and 89+/-6mus, respectively. This enantiomeric selectivity is attributed to a difference in dissociation rates (competing with the radiative emission process) for the diastereoisomeric inclusion complexes dealt with, which have a 2:1 stoichiometry (alpha-CD:CQ:alpha-CD). Time-resolved RTP detection using different delay times enables the determination of the two enantiomers in a mixture without involving a separation technique. The minimum detectable fraction of (+)-CQ in a 2mM sample was 13%.
已证明，在脱氧水溶液中，樟脑醌（CQ）与环糊精（CDs）之间的包合物表现出相对较强的室温磷光（RTP）。在测试的各种环糊精中，α-环糊精显示出最强的RTP信号。有趣的是，CQ的两种对映体的这些信号存在显著差异；（+）-CQ的磷光寿命比（-）-CQ长约四倍，分别为352±16和89±6微秒。这种对映体选择性归因于所处理的非对映体包合物（化学计量比为2:1，即α-环糊精:CQ:α-环糊精）的解离速率差异（与辐射发射过程竞争）。使用不同延迟时间的时间分辨RTP检测能够在不涉及分离技术的情况下测定混合物中的两种对映体。在2mM样品中，（+）-CQ的最低可检测分数为13%。
