Solid phase extraction of the zwitterionic detergent chaps.

Multiple techniques for solid phase adsorption of 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS) were evaluated. Both the porous polystyrene divinylbenzene matrices (BioBeads SMTM) and Extracti GelTM D reduced CHAPS to significantly below its critical micellar concentration while Extracti-GelTM removed CHAPS to below detectable limits. Bio-Bead extraction of CHAPS correlated with the surface area of the bead type. SM-16 beads, with the largest effective surface area, removed nearly 97% of the detergent. For a given amount of detergent and mass of Bio-Beads, the ratio of sample to total bead volume significantly affected CHAPS adsorption. Total protein recovery with the Extracti-GelTM was approximately 97%. Protein recovery in the samples treated with Bio-Beads varied from 56-95%. Chromatographic rather than batch processing yielded optimum recoveries. CHAPS can be effectively removed from dilute protein solutions by solid phase adsorption and this technique offers significant advantages over standard dialysis or gel filtration methods.