in-laboratory processing

in analytical chemistry
The selection, removal and preparation of the test (or analytical) portions from the laboratory sample. The processing may include a reduction in the size of the unit(s) (division) and particle size (reduction), as well as mixing to achieve homogeneity.
Source:
PAC, 1990, 62, 1193 (Nomenclature for sampling in analytical chemistry (Recommendations 1990)) on page 1204