Abstract: An alkyl-phenyl bonded a stationary phase for use in reversed-phase liquid chromatography, having five to ten carbon atoms in the alkyl group, is disclosed. The alkyl-phenyl bonded phase has its unique selectivity, and it is chemically stable in both acidic and basic environments as well as having high retention capacity, hence high resolution. A method for preparing the alkyl-phenyl bonded phase and a column inside of which the alkyl-phenyl bonded phase is packed with are also disclosed. Additionally, a method for performing liquid chromatography and a mixed stationary phase which has more than one alkyl-phenyl phases are disclosed.

Abstract: A protected fused-silica capillary liquid chromatography (liquid chromatography) column is shielded inside a single flexible tubing, which has the same length as the capillary and is integrated with the capillary in the packing process. The column has the advantages of a fused-silica capillary liquid chromatography column combined with the benefits of the shield tubing which makes the column more accurate, durable, and convenient to use, and less expensive to produce.

Abstract: A new type of guard cartridge has been provided to prevent contamination of liquid chromatography (LC) columns by particulate and soluble contaminants. The cartridge is prepared by packing an empty tube with a chromatographic stationary phase and the packed tube is then sealed on both ends with porus sheets held in place by two collars. The cartridge gives minimum disturbance on column performance and significantly decreases the cost of production.