cleanup
Cleanup is tidying a messy sample extract before measurement — getting rid of the gunk that isn't your analyte but would otherwise foul the instrument or muddle the result. Think of straining and skimming a stock before serving: the soup's flavour stays, but the bones, fat, and scum that would ruin the dish are taken out first.
Technically, cleanup removes interfering compounds and matrix junk from an extract while leaving the analyte behind, using a separation step that exploits a chemical difference between them. Fats might be frozen and filtered out, pigments adsorbed onto a column, large molecules screened away — whatever clears the path so the analyte arrives at the detector relatively alone.
It matters because a dirty extract can clog columns, coat detectors, suppress signals through matrix effects, and bury the analyte's peak among interferences. The trade-off is real: every cleanup step risks losing some analyte along with the junk, and it adds time and reagents — so the art is removing enough interference without sacrificing too much of what you came to measure.
Before testing fatty fish for trace pesticides, the extract is passed through a column that traps the fat and pigments, letting the pesticides flow through clean — so they don't smother the analysis.
Strip away the junk; keep the analyte for the detector.
Cleanup, extraction, and preconcentration often run together and even use the same hardware — a single SPE cartridge can extract, clean up, and concentrate in one pass. The labels describe the purpose: extraction pulls the analyte out, cleanup removes interferences, preconcentration crowds the analyte into less volume.