CHARACTERISTICS AND APPLICATIONS OF A NEW HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY GUARD COLUMN

A new HPLC guard column has been developed that significantly increase s chromatographic efficiencies when placed in series with an analytica l column. When compared with other commercially available guard column s, only the Sentry guard column was found to result in increased plate s. All other guard columns evaluated resulted in a 10-60% loss of chro matographic efficiency. By stressing the Sentry guard columns with inj ections of crude mouse serum it was shown that analytical column lifet imes could be extended. The Sentry guard columns have also been shown to have higher capacity for contaminants than most competitive guard c artridges. Over 8000 injections of a standard mixture have been made o n the Symmetry C-8 analytical columns protected by Sentry guard column s with no significant change in the analytical columns' performances.