Hemoglobin cation-exchange

Alpert has shown [47] that poly(succinimide)-silica can be further hydrolyzed to poly (aspartic acid)-silica or condensed with [3-alanine in aqueous solution to form a covalently bonded copolymer of 2-carboxyethyl aspartamide and aspartic acid. The content of carboxyl groups generated by this way has not been quantified directly, but the cation-exchange hemoglobin capacity has been measured for a series of the packings. Thus, the optimal concentration of poly(succinimide) used in the synthesis was found to be 2 5%. 

Ion-exchange chromatography separates hemoglobin variants on the basis of charge. The cation exchange resin (neg-... 

Mario N, Baudin B, Aussel C, Giboudeau J. Capillary isoelectric focussing and high-performance cation-exchange chromatography compared for qualitative and quantitative analysis of hemoglobin variants. Clin Chem 1997 43 2137-42. 

Ou C-N, Rognerud CL. Rapid analysis of hemoglobin variants by cation-exchange HPLC. Clin Chem 1993 39 820-4. 

Rioux, Godart C, Huntrel D, Mathis M, Bimet C, Bardakjian J, et al Cation-exchange HPLC evaluated for presumptive identification of hemoglobin variants. Clin Chem 1997 43 34-9. 

Another new technology that offers promise for commercial biotechnology purifications is the use of parametric pumping with cyclic variations of pH and electric field. This has been described by Hollein and cowork-ers.fi26) They worked with human hemoglobin and human serum albumin protein mixtures on a CM-Sepharose cation exchanger. The extensive equations they reported for parametric separations allow analysis of other systems of two or more proteins which may be candidates for this type of separation. 

F12. Fliickiger, R., and Woodtli, T., Effect of temperature on quantifying glycated (glycosylated) hemoglobin by cation-exchange chromatography. Clin. Chem. 31, 114-117... 

Pastore A, Francesca MA, Tozzi G, Maria GL, Federici G Berlin E, Lo Russo A, Mannucci L, Piemonte F. Determination of glutathionyl-hemoglobin in human erythrocytes by cation-exchange high-performance liquid chromatography. Anal Biochem 2003 312 85-90. 

A new automatic HPLC system using the Bio-Rad MA 7 polymeric cation-exchange material has been used to screen newborns for sickle cell anemia and other hemoglobinopathies [16]. The method is reported to resolve hemoglobins F, A, S, C, E, and D. 

PolyCAT A, a weak cation exchanger with polyaspartic acid linked to silica [39,40], has been used for the determination of HbA c [41,42] and for identification of several minor hemoglobin variants [10,43]. The separation of HbA c from other Hb components such as acetylated Hb [33] and HbF depends critically on buffer composition, particularly on the pH and salt gradient. It is often necessary to make minor modifications in the steepness of the salt gradient to obtain good separation. 

Ou CN, Buffone GJ, Reimer GL, Alpert AJ. High-performance liquid chromatography of human hemoglobins on a new cation exchanger. J Chromatogr 1983 266 197-205. 

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