猝灭方法广泛用于通过添加过量猝灭剂引起的探针抑制效率(IE)来评估指定反应性物种的贡献。然而,对于能力弱的反应性物种,如单线态氧(1O2),淬火结果容易产生歧义。在这项研究中,以糠醇(FFA)为探针,通过亚甲基蓝-N可见光增敏,讨论淬火,1O2的干扰消除和污染物降解能力。发现了由1O2产生的猝灭和中断引起的FFA转化的抑制。猝灭受猝灭剂用量和能力的影响,这取决于二阶速率常数(k)。k高意味着能力强,并且需要更少的剂量来实现相同的IE。猝灭剂消耗的反应性物种的计算比率与实验IE之间的比较有助于判断1O2产生的中断。没有有机溶剂(甲醇,乙醇,异丙醇,正丁醇,异丁醇,叔丁醇,四氢呋喃,乙腈,丙酮和氯仿)清除了1O2,可用作其他反应性物质的筛选剂(例如,羟基自由基)会中断1O2贡献评估。此外,1O2无法降解大多数选定的污染物。这些结果鼓励正确使用猝灭剂和更好的实验设计。
Quenching method is widely used to assess the contribution of specified reactive species through the probe inhibition efficiency (IE) caused by adding excessive quencher. However, for reactive species with weak ability such as singlet oxygen (1O2), the quenching results are prone to ambiguity. In this study, an 1O2 system using furfuryl alcohol (FFA) as a probe was successfully constructed by methylene-blue-N vis-
photosensitization, to discuss the quenching, interference elimination and pollutant degradation ability of 1O2. Inhibition of FFA transformation caused by both quenching and interrupting of 1O2 production was found. The quenching is affected by quencher dosage and ability, which depends on the second-order-rate constant (k). A high k means a strong ability, and less dosage is required to achieve the same IE. Comparison between the calculated ratio of reactive species consumed by quencher and experimental IE helps to judge the interruption of 1O2 production. None of the organic-solvents (methanol, ethanol, iso-propanol, n-butanol, iso-butanol, tert-butanol, tetrahydrofuran, acetonitrile, acetone and chloroform) scavenged 1O2, which would be used as screening-agent for other reactive species (e.g., hydroxyl radicals) that would interrupt 1O2 contribution assessment. Besides, 1O2 was powerless to degrade most selected pollutants. These results encourage proper use of quenchers and better experimental design.