Aliquots

An aliquot is a precisely measured portion of a larger sample that is representative of the whole. The term, derived from Latin aliquot meaning "some, several," is widely used in laboratory science and analytical chemistry. The purpose is to allow analysis, characterization, or testing without consuming the entire sample. Aliquotting supports reproducibility and traceability, enables calibration and inclusion of replicates, and minimizes the impact of heterogeneous samples or degradation during storage and handling.

In practice, aliquots are prepared using calibrated instruments, such as micropipettes or volumetric devices, and placed in appropriate containers under clean or sterile conditions when biological material is involved. Proper labeling, documentation, and chain of custody are essential because aliquots must be traceable to the original sample. Aliquot storage is typically at defined temperatures and conditions to preserve integrity; repeated handling should be minimized to prevent contamination or changes in composition.

Common applications include preparing standards, running multiple analyses from a single source, preserving material by aliquoting before freezing, and distributing samples for interlaboratory testing. The choice of volume depends on the assay, concentration, and available equipment. Aliquoting is a routine practice in clinical laboratories, environmental testing, pharmaceutical development, and research settings.

In mathematics, aliquot has a different meaning related to divisors of a number, such as the aliquot sum, which is the sum of proper divisors. This reflects the shared etymology but a distinct concept from laboratory aliquots.