Chromatography sulfhydryl group

After It has been determined which chain In the variant Is aberrant, specific structural studies are required. Several procedures are available which differ from one laboratory to the other and Include chain separation by column chromatography, modification of the sulfhydryl groups through reaction with... 

For removal of excess DTT, a protein of molecular weight greater than 5000 may be isolated by gel filtration using Sephadex G-25. To maintain the stability of the exposed sulfhydryl groups, include 1—10 mM EDTA in the chromatography buffer. The presence of oxidized DTT can be monitored during elution by measuring the absorbance at 280 nm. The protein should elute in the first peak and the DTT reaction products in the second peak. 

CLARKSON That thing about methylmercury chloride and its rapid penetration across membrane bothers me. It is not at all clear that methylmercury chloride will be present in the waters in their natural condition. Methylmercury chloride is a very lipid soluble compound of methylmercury we convert methylmercury to methylmercury chloride which is extracted into benzene for gas chromatography. And it is not at all clear that the conclusions with methylmercury chloride would apply to the forms of methylmercury which naturally exist under natural conditions and which I would imagine would be bound to a sulfhydryl group in an amino acid or protein. This would be water soluble, not lipid soluble as methylmercury chloride is. 

Srinivas, N.R., Mamidi, R.N. (2003) Bioanalytical considerations for compounds containing free sulfhydryl groups. Biomedical Chromatography, 17,285-291. 

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