Low and High pH Stability of an Agilent Poroshell HPH C18

Version 1

    Application Note



    The stability of an HPLC column is one of the critical factors that determines the success of a method. During the development of an RPLC analysis protocol, and anticipating its validation, chromatographers usually consider several issues. One of the most important is how long the column will last under a specific set of analysis conditions. Silica has many properties that make it excellent as a support for reversed-phase HPLC columns. However, its solubility increases substantially as the mobile phase reaches pH 7-8 and above. In a study of high pH silica HPLC column stability at Rockland Technologies, several key findings were made; end-capping protected the silica from dissolution, densely bonded phases increased column stability, and organic mobile phase buffers yielded significantly longer column life than phosphate buffers at similar pH. Studies have shown that bonded-phase packing degradation at pH 9-10 was mainly due to silica support dissolution, and did not primarily result from the hydrolysis of covalent siloxane bonds. In principle, the chemical and thermal stability of RP columns can be enhanced by the improvement and development of substrates and bonding chemistry.


    Publication number: 5991-6525EN

    Publication Date: January 22, 2016