Expiration dating for laboratory reagents and solutions
Exposure of materials to heat or direct sunlight should be avoided.
If a material is easily oxidized, it may be stored with a layer of nitrogen.
Standards Laboratories use primary and secondary standards to determine material results and equipment calibration.
The current compendia (European Pharmacopeia [Ph Eur], Japanese Pharmacopeia [JP], and United States Pharmacopeia [USP]) typically define the process for re-standardizing the most commonly used volumetric solutions.
The preparation of all solutions prepared in the laboratory must be documented.
For example, solutions that are prone to microbial growth, such as Some reagents and solutions may be used past their expiration date if the material can be recertified or re-qualified.
For example, it is common to re-standardize or recertify volumetric solution upon use or at monthly intervals.
The finished product reserve samples are maintained for one year past their expiration date.