摘要
在多聚磷酸介质条件下,对酸性高锰酸钾和高良姜素化学发光新体系的发光现象进行了研究,并通过测定反应的化学发光光谱、紫外吸收光谱、荧光光谱和微量电位滴定曲线对其发光体的确定提供了实验依据。实验数据表明,在0.1mol·L-1多聚磷酸溶液中,当高锰酸钾和高良姜素的量比为6∶5时,体系有最强的化学发光,在氧化剂过量的条件下,化学发光强度与高良姜素浓度在一定范围成正比关系。此外,由体系的化学发光光谱与高锰酸根离子的电子吸收光谱之间有镜像对称性关系的现象,证明了主发光体应来源于高锰酸钾;发光动力学实验还证明该发光体不是单一型体,伴随发光过程发光体有歧化反应现象。根据实验结果,对该体系可能的发光机理进行了讨论,提出高锰酸钾和高良姜素化学发光的主要发光体来源于高锰酸根离子的还原产物且为氧化还原反应过程中产生的激发态Mn(Ⅱ)和Mn(Ⅲ)型体,通过高良姜素氧化生成的活性游离基产物而产生激发态的Mn(Ⅱ)型体是生成发光体的主要途径。该化学发光强度与高良姜素含量成线性关系,以此可以进行定量分析;而由歧化过程形成的激发态Mn(Ⅲ)的发光行为却会干扰高良姜素含量与总发光强度之间的线性关系,不利于定量分析。
In polyphosphoric acid （PPA） solution, a novel acidic potassium permanganate-galangin chemilu- minescence system was studied. By means of chemiluminescence spectra, UV-Vis absorption spectra, fluorescence spectra and micro-potentiometric titration method, it was discovered that some experimental evidences for confirming the emission species of the system. The results indicated that the CL intensity of system reached maximum when the molar ratio of potassium permanganate to galangin was 6：5 and the CL intensity of system was proportional to galangin concentration within certain concentration extent when existing excessive oxidant. In addition, the fact that there exists mirror symmetry between electronic absorption spectra of permanganate ion and chemiluminescence spectra of the redox system showed that main luminophor of the chemiluminescence system certainly came from the reductive products of permanganate ion. The chemiluminescence kinetic results also indicated that along with the chemiluminescence reaction, the emission species was hardly the single species but could be converted into other species by the some dismutation process. On the grounds of experimental results, a possible reaction mechanism was also proposed, and it was confirmed likewise that the main emission species of the chemiluminescence redox system was more probably contributed of the excited Mn（Ⅱ） and Mn（Ⅲ） species produced by the redox system. Furthermore, the production of excited Mn （Ⅱ） by the active radical which came from galangin＇s oxidative production was the main approaches for chemiluminescence reaction. The CL intensity of excited Mn（Ⅱ） had to be of linear relationship to galangin concentration,thus can be applied to quantitative analysis; but the production of excited Mn （Ⅲ） by the dismutation process would disturb the chemiluminescence behavior between the CL signal response and galangin concentration and not to be beneficial to chemiluminescence analysis.
出处
《发光学报》
EI
CAS
CSCD
北大核心
2008年第3期583-590,共8页
Chinese Journal of Luminescence
基金
甘肃省自然科学中青年基金资助项目(2007GS03596)
关键词
化学发光
高良姜素
高锰酸钾
chemiluminescence
galangin
potassium permanganate
