Newcrom R1 is a special reverse-phase column with low silanol activity. The stationary phase of Newcrom R1 is generally stable at basic pH values, with a recommended pH range of 1.0 to 10.0.
For example, a test was performed where the column was operated at pH 10.6, injecting a model mixture of neutral, basic, and acidic compounds. This experiment took over 15 hours, and after almost 200 injections, no significant loss or changes in retention were observed. However, despite the fact that this stationary phase is stable at high pH, it is recommended to use an acidic mobile phase for column storage. A mobile phase composition with 0.1% phosphoric or formic acid in a 50/50 mixture of MeCN/H2O should be an ideal solution for both long and short-term storage.
