Lab glossary

An organic compound with an amino group, a carboxyl group and a side chain bonded to one central carbon atom. Twenty amino acids are specified by the standard genetic code.

The ordered list of amino acids in a peptide or protein, read from the N-terminus (free amino end) to the C-terminus (free carboxyl end) and written with one-letter or three-letter codes.

A quantity of material made in one production run under the same conditions. A lot number identifies the batch so that a test record can be matched to the vials filled from it.

A document from a testing laboratory that lists the tests run on one named batch and the values measured. It describes that batch and no other.

A unique numerical identifier that the Chemical Abstracts Service assigns to a chemical substance. It is written as three groups of digits separated by hyphens, for example 7732-18-5 for water.

The plot a chromatography instrument records: detector signal on one axis and time on the other, with one peak for each component that was separated from the sample.

An unbroken series of temperature-controlled storage and transport steps that keeps a temperature-sensitive material within a set range from the point of manufacture to the point of receipt.

A unit of mass equal to one twelfth of the mass of a carbon-12 atom, about 1.66054 x 10^-27 kg. It is the unit used to state the mass of a single molecule.

A liquid used to dissolve or thin another substance. It is a solvent chosen to suit the substance it is paired with.

High-performance liquid chromatography. An analytical technique in which a liquid sample is pumped under pressure through a packed column. Components of the sample leave the column at different times and a detector records each one as a peak.

Latin for "in glass". Work carried out in a controlled setting outside a living organism, such as in a test tube, a culture dish or an analytical instrument.

Freeze-dried. Water is removed from a frozen sample by sublimation under vacuum, which leaves a dry solid, often a loose cake or powder.

An analytical technique that turns molecules into ions and measures their mass-to-charge ratio (m/z). It is used to determine the molecular mass of a compound.

A notation that gives the number of atoms of each element in one molecule of a compound. Water is H2O.

The mass of one mole of a substance, given in grams per mole (g/mol). Also called molar mass. Stated in daltons, it is the average mass of one molecule.

A molecule made of two or more amino acids joined in a chain by peptide bonds, a type of amide bond. Chains of roughly fifty or more amino acids are usually called proteins.

A single unbranched chain of many amino acids joined by peptide bonds. A protein is made of one or more polypeptide chains.

The fraction of a sample that is the named compound, stated as a percentage. In HPLC it is commonly reported as the area of the main peak divided by the total area of all peaks, which depends on the method and the detector used.

Returning a dried material to a liquid state by adding a solvent. The term is used for lyophilized solids.

A designation for materials supplied for laboratory research and analytical work. Products are sold for Research Only and not for Human Consumption.

The greatest amount of a substance that dissolves in a given amount of solvent at a stated temperature.

A small glass or plastic container for laboratory samples and reagents, usually closed with a stopper and a crimped cap.