Overview

The API 5000 system is designed for quantitative analysis of small molecules. This application involves measurement of specific molecular weight compounds, usually a drug or metabolite in urine or other body fluid, and their resulting fragment ions for determining the exact quantity of the compound in the sample of interest. Quantitation is performed using a standard curve of mass spectrometer signal intensity for various known concentrations of the compound. The signal in the test sample is compared to the standard curve to determine the concentration. The typical scan type used for this application in the API 5000 system, as well as all triple quadrupole instruments, is MRM (Multiple Reaction Monitoring).