What is on-column hydrolysis and what causes it? What will be the effect on TYPE-C Silica phases?
[top] Hydrolysis is a common degradation mechanism, which is facilitated by the presence of acids or bases in solution or on the surface of solids the liquid is in contact with. With solids in contact with liquids, the larger the surface area the greater the potential for hydrolysis. Irregular, type A & type-B HPLC phases all have by design very high surface to volume ratios plus Si-OH groups populate this surface. Even a fully end capped traditional phase can have 30 to 50% free silanols on its surface. Using photodiode array detectors and HPLC/Mass Spec has highlighted this degradation activity. Certain analytical disciplines such as Natural Product Bio-actives and Forensic Science have shown that 10 to 20% of bio-active compounds may hydrolyze quantitatively on-column due to the conditions inside the HPLC Column. Historic analyses were usually made by these disciplines, of degradation products and not the injected material due to this activity in the column. TYPE-C Silica based prod
