Binding of bile acids by cellulose-based cationic adsorbents

Abstract

One of the ways to regulate the cholesterol level in the blood is by adsorption of overproduced bile acids from the gastrointestinal tract. For this purpose, synthetic anion exchangers have been in clinical use for many years. The efficiency of these sorbents is rather low, because of their low binding capacity. In this work, cationic cellulose derivatives of different structure were evaluated as sorbents for binding of bile acids. It was found out that adsorption of bile acids is highly affected by pH. This was explained taking into account dissociation constants of the bile acids, as well as of the functional groups of the adsorbents. It has been showed that the cellulose-based adsorbents are more effective bile acid binders than the commercial ones, due to their more accessible structure. Comparing cellulosic adsorbents, the macroporous adsorbent DEAE-Granocel in all cases showed the best sorption capabilities.