Gawron AJ, Lunte SM. Optimization of the conditions for biuret complex formation for the determination of peptides by capillary electrophoresis with ultraviolet detection.
Electrophoresis 2000;
21:2067-73. [PMID:
10879968 DOI:
10.1002/1522-2683(20000601)21:10<2067::aid-elps2067>3.0.co;2-5]
[Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Capillary electrophoresis with UV detection was utilized to optimize copper complexation conditions for the analysis of neuropeptides. Complexation was confirmed by monitoring the response at a visible wavelength. Four complexation strategies were used to compare the UV response of native peptides and their respective copper complexes. All four strategies resulted in complete complexation, but on-capillary complexation provided significant advantages over precapillary and pre-/on-capillary. An increase in UV absorbance along with peak stacking resulted in a significantly greater response using the on-capillary technique. Also, on-capillary complexation does not require dilution of the sample. The effects of temperature and copper concentration were also investigated. The utility of this method for the separation of an enkephalin peptide mixture is presented.
Collapse