A photometer used for the measurement of the absorbance of light in solutions, gases, or transparent or opaque solids, such as polished glass. Typically used at 280nm to determine the concentration of proteins related to antibody production.


The adjusting of a solution’s pH through the addition of an acid or a base. Performed by automatic titrators or manually with the use of a pH meter.

Ultrafiltration (UF) / Diafiltration (DF)

A technique that uses special filters to sort and/or wash solutions on a molecular level. May also be referred to as concentration and dialysis. Pictured is a Pellicon UF/DF system with tubing running through a peristaltic pump. The lines are inserted into an Erlenmeyer flask containing the UF/DF membrane storage solution.


Confirming that the outcome is repeatable and is what as expected.