Premium
Long‐chained gemini surfactants for semipermanent wall coatings in capillary electrophoresis of proteins
Author(s) -
Liu Qian,
Yuan Jinbin,
Li Yanqing,
Yao Shouzhuo
Publication year - 2008
Publication title -
electrophoresis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.666
H-Index - 158
eISSN - 1522-2683
pISSN - 0173-0835
DOI - 10.1002/elps.200700391
Subject(s) - pulmonary surfactant , coating , cationic polymerization , bromide , chromatography , capillary action , capillary electrophoresis , materials science , alkyl , chemistry , electrophoresis , buffer (optical fiber) , chemical engineering , bifunctional , adsorption , composite material , polymer chemistry , organic chemistry , biochemistry , engineering , telecommunications , computer science , catalysis
In this paper, we presented the first example of using gemini surfactants as semipermanent coatings in CE for protein separation. These coatings are based on the self‐assembly of a series of cationic gemini surfactants, alkanediyl‐ α , ω ‐bis(dimethylalkylammonium bromide) ( m ‐ s ‐ m ), on the capillary wall. The coatings can keep stable for a long time without surfactant in the buffer, e.g. , after the surfactants were removed from the buffer, the reversed EOF only decreased by 3.6 and 3.9% for 18‐2‐18 and 16‐2‐16 coatings over 60 min under continuous electrophoretic conditions. The coating stability increased with the alkyl chain length m . The double long chains of geminis ( m ≥ 14) yielded a good coating stability; meanwhile, the spacer group acted as an EOF modifier. Thus, this bifunctional surfactant coating provided a new buffer‐independent method for EOF control. For 18‐ s ‐18 series, the best coating stability and largest EOF were obtained at s = 10. Ranging s from 3 to 10 yielded a linear fine‐tuning of EOF and thereby allowed the adjustment of the protein apparent mobility. Highly efficient separation (>500 000 plates/m) was achieved with all the 18‐ s ‐18 coatings. Excellent run‐to‐run and day‐to‐day reproducibility (RSD of migration time ≤0.7 and 4.3% for run‐to‐run and day‐to‐day assays, respectively) and fine recoveries (97.5–100.1%) of the protein samples indicated that the gemini semipermanent coatings were quite effective for the wall adsorption suppression of proteins.