Schach, Denise Kristine

Mass spectrometric method for determining a relative quantity of at least one analyte present in a first biological sample relative to the quantity of the same at least one analyte present in a second biological sample, the method comprising the steps of: providing the first biological sample comprising the at least one analyte labeled with a first isobaric mass tag; providing the second biological sample comprising the at least one analyte labeled with a second isobaric mass tag different from the first isobaric mass tag; mixing the first biological sample with the second biological sample to obtain a sample mixture; introducing, by direct inlet, a stream of the sample mixture into an ionization source; ionizing the stream of the sample mixture to generate labeled analyte ions of the at least one analyte labeled with the first and labeled with the second isobaric mass tag; separating the labeled analyte ions from other components of the sample mixture based on their ion mobility; fragmenting the separated labeled analyte ions to release reporter ions from the first and second isobaric mass tags; and measuring signal intensities of the reporter ions at their respective mass-to-charge ratios and determining therefrom the relative quantity of the at least one analyte present in the first biological sample relative to the second biological sample based on the measured signal intensities.

The present invention relates to a clinical diagnostic system, a method for determining the presence or level of at least one analyte of interest in a biological sample, a kit and the uses thereof for efficiently and/or robust detection of an analyte of interest.