About sound science, stable isotope dilution, blasphemy and heresy.
The molar ratio between an analyte and its equal labeled with stable isotope(s), used as a bioanalytical IS, is here suggested as an essential (and currently not commonly applied) validation parameter. This parameter, when calculated and measured, gives the possibility for the bioanalyst to compare calibration graphs and QC samples over time independently of added amount of IS. Additionally, when QC samples and calibration samples do not agree it is obvious to identify where the discrepancies are. Whether calibration samples are needed when this parameter is extensively and carefully validated and understood, is also discussed.
Active Biotech AB, Box 724, Scheelevagen 22, Lund, SE-220 07, Sweden. leif.svensson@activebiotech.com
Leif D
LD
Svensson
D002138:Calibration; D002851:Chromatography, High Pressure Liquid; D059788:Dried Blood Spot Testing; D007201:Indicator Dilution Techniques; D007554:Isotopes; D011786:Quality Control; D012586:Science; D053719:Tandem Mass Spectrometry
D007554:Isotopes