Method and apparatus for improved resolution chromatography

An apparatus for column chromatography, comprising:

• a chromatography column having an inlet assembly;
• the inlet assembly including:
• an outer surface;
• a plurality of inlet ports comprising, at least one central inlet port and at least one peripheral inlet port;
• and,
• an inlet frit assembly including:
• a plurality of separate porous frit sections comprising a central frit section adapted to receive fluid from the at least one central inlet port and an annularly surrounding concentric frit section adapted to receive fluid from the at least one peripheral inlet port, wherein the annularly surrounding concentric frit section is separated from the central frit section by a non-porous flow barrier, whereby mobile phase entering any one of the porous frit sections is prevented from laterally flowing into an adjacent frit section by the non-porous flow barrier;
• wherein the at least one central inlet port and the at least one peripheral inlet port extend from the outer surface of the inlet assembly to the central frit section and to the annularly surrounding concentric frit section respectively;
• wherein the inlet assembly has a first solvent delivery system fluidically coupled with the at least one central inlet port and a second solvent delivery system coupled with the at least one peripheral inlet port.