槲皮素-铝配合物合成过程中紫外-可见时间分辨吸收光谱

用氘灯光源室提供连续光,采用增强型光谱探测器ICCD拍摄光谱,利用DG535脉冲发生器对测量系统进行同步控制,实时测得了槲皮素与Al3 反应形成配合物过程中的紫外-可见时间分辨吸收光谱。光谱的曝光时间为1μs,每隔20ms拍摄1幅光谱,一次连续拍摄50幅。所拍光谱图清楚地显示出当反应进行到40ms时,槲皮素的两个特征峰254和374nm已消失,但在384nm处出现一过渡产物的吸收峰,而Al3 在300nm左右的特征吸收带仍存在;随着反应的进一步进行,过渡产物及Al3 在消失,槲皮素-铝配合物的特征峰267和436nm产生并逐渐增强;反应进行到980ms时,Al3 的特征吸收带完全消失,槲皮素-铝配合物的两特征吸收峰增至最强。整个反应过程在1s内已完成。文章结果提供了槲皮素具有清除Al3 的实验依据。

Time Resolved UV-Vis Absorption Spectra in Synthetic Process of Quercetin Complex with Al3+

With a deuterium light source was used to provide the continuous light, the time resolved UV-Vis absorption spectra in the synthetic process of quercetin complex with Al3+ were measured by using an intensified ICCD spectroscopic detector. The measuing system was controlled synchronously by using a digital delay generator DG535. A total of 50 spectra with the exposure time of 1 micros for each spectrum and the time interval of 20 ms between two successional spectra were acquired. Results showed clearly that the typical bands centered at 254 and 374 nm of quercetin disappeared at 40 ms after the reaction started; at the same time, an absorption band centered at 384 nm of a transitional product appeared, and the typical absorption band centered at 300 nm of Al3+ still existed; with the reaction progressing, the bands of the transitional product and Al3+ disappeared, and the new bands centered at 267 and 436 nm of the complex of quercetin with Al3+ appeared and became stronger gradually; at 980 ms, the typical absorption band of Al3+ disappeared completely and the two typical absorption bands of the complex increased to the strongest. The synthetic reaction of quercetin complex with Al3+ finished within one second. The process of Al3+ being scavenged is shown in the spectra obviously. The prensent results provide experimental evidence for the Al3+ scavenging ability of quercetin.