Theoretical and experimental investigations on relationship between Kohlrausch regulating function/inequality and moving reaction boundary in electrophoresis

Laboratory of Analytical Biochemistry and Bioseparation, Key Laboratory of Microbiology of Educational Ministry, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
Journal of Separation Science (Impact Factor: 2.74). 06/2009; 32(12):2123-31. DOI: 10.1002/jssc.200800765
Source: PubMed


Kohlrausch regulating function (KRF) has been well defined from a moving boundary system for over 50 years. Recently, a series of theoretical and experimental studies were carried out on the concept of moving reaction boundary (MRB), including moving precipitate boundary, moving neutralization boundary and moving chelation boundaries (MCB). However, there has not been any direct evidence to show whether the KRF has validity for a MRB or not. In this paper, the KRF is derived from the equation of MRB under condition of nonzero boundary velocity. The result directly shows the relation between the KRF and a MRB. The relation is verified by some experimental and simulation results on MCB and moving neutralization boundary as well as Svensson's classic IEF. Furthermore, a Kohlrausch inequality was defined from the equation of MRB and was further proved by numerous data. The results show that we can use the KRF for the investigation on a MRB under the condition of nonzero boundary velocity, whereas we ought to notice with great attention that the KRF does possibly have invalidity under some special cases, such as stationary electrolysis and IEF. The findings hold an evident significance to the study of a MRB with the KRF.

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