Figure 1.
Instrument configuration. An adjustable flow splitter was utilized to support the reduced mobile phase flow rate. Mobile phase flow through the analytical column and the electrospray ionization needle was maintained during the on-line desalting step without an additional liquid chromatography pump due to the T-union connecting the adjustable splitter, the auto sampler, and the divert valve port, which could be switched to the trap column or to the analytical column.