Hybrid supercritical fluid chromatography method

A method of supercritical fluid or liquid chromatography of a product P, said method comprising the steps of:

• an analytical step according to an analytical route comprising:
• an analytical pumping operation comprising a first pumping of a first aliquot of a supercritical fluid or liquid and a second pumping of a first aliquot of a modifier,
• an injection operation of a first aliquot of at least one sample of the product P or of at least one constituent of the product P into at least one chromatography column, the product P or the constituent of the product P being eluted with the first aliquot of the supercritical fluid or liquid and the first aliquot of the modifier,
• a separation operation of the constituents of the product P,
• a detection operation of the composition of the product P or of the constituents of the product P,
• a switching step comprising:
• a verification operation comprising a substep of comparing the analysis results with one another or with reference values representing optimum analysis conditions, and
• an automatic route change operation between the analytical route and a preparative route as a function of the preceding comparison,
• a preparative step resulting from the automatic route change operation of the switching step, wherein the preparative route comprising:
• a preparative pumping operation comprising a first pumping of a second aliquot of the supercritical fluid or liquid and a second pumping of a second aliquot of the modifier,
• another injection operation of a second aliquot of the at least one sample of the product P into at least one chromatography column, product P being eluted in the chromatography column by the second aliquot of the supercritical fluid or liquid, and the second aliquot of the modifier,
• another separation operation of the constituents of the product P,
• a detection operation of the constituents of the product P,
• another collection operation of one or more constituents of the product P in an open bed at atmospheric pressure, and
• a preparative recycling operation of at least a portion of the second aliquot of the supercritical fluid, wherein the recycling operation occurs only upon completion of the collection operation of the preparatory stage.