Control Subtraction
In chemical characterization studies, such as those performed for medical device biocompatibility testing under ISO 10993-18, it is imperative that the final dataset is limited to extractables and leachables from the test article itself and not from exogenous chemicals introduced during the experimental process, such as from solvents, glassware, and instrumentation. Controlling for these introduced species is expected as part of these studies, but there is a lack of industry standardization from guiding agencies in defining an acceptable approach. EAG Laboratories employs control subtraction through a conservative approach that corrects the chromatographic area of a species in a test sample by subtracting the chromatographic area of the corresponding species in the appropriate control. By performing control subtraction to remove any area contributions introduced during the experimental process, the compound’s endogenous signal can be more accurately quantified.

Data Processing and Scripting
EAG utilizes Thermo Scientific™ Compound Discoverer™ Software (CD) for the alignment, integration, and initial identification of liquid chromatography-mass spectrometry (LC-MS) data.