Re-certification of hydroxyvitamin D standards by isotope pattern deconvolution

From fundamentals in calibration to modern methodologies: A tutorial for small molecules quantification in liquid chromatography–mass spectrometry bioanalysis

“…In contrast to traditional analytical methods that rely on signal intensity, IPD is established on signal ratio between the isotopes of the molecule of interest and an analog with an enriched isotopic composition (i.e., SIL). The IPD is considered to be one of the most reliable and highest metrological methods and is commonly used by chemical manufacturers to calculate SIL isotopic enrichment and purity [143][144][145][146]. The isotopic abundance and concentration of the isotope labeled analog can be obtained by reverse isotope dilution mass spectrometry (i.e., a calibration against a high purity solution of the natural analyte prepared from a gravimetric solution of a suitable reference material) [147].…”

“…The labeled compound is then added to the reference material, resulting in isotopic dilution. The comparison between theoretical and experimental isotope overlap allows to determine the SIL isotopic enrichment, chemical purity and concentration [144]. Once the SIL solution has been characterized by isotope dilution mass spectrometry it can be used as a calibrant for IPD quantification.…”

Isotope pattern deconvolution as a successful alternative to calibration curve for application in wastewater-based epidemiology

“…IPD calculation approach has been tested for the rapid and reliable quantifications of different compounds in several complex matrices, such as urine [ 24 – 27 ], serum [ 28 ], food [ 29 ] and environmental samples [ 23 , 30 – 33 ]. Recently, the power of IPD for the easy and accurate re-certification of vitamin D standards [ 34 ] has been demonstrated.…”