As the molecular structure of BAs is remarkably different from each other, it is hard that the three internal standards can well calibrate all the analytes.
Given the lack of isotope-labeled BAs standards on the market, Mayr et al.
first synthesized and purified 10 isotope-labeled BA standards, then developed a HPLC–MS/MS method to determine 14 BAs with those newly prepared isotope-labeled BAs as internal standards.
Their work proved to be an efficient but costly proposal, because the vast majority of energy and cost was spent on the preparation of isotope-labeled BA standards.
In our work, the isotopic internal standards of all analytes can be easily obtained by isotope-coded derivatization.
The proposed method could accomplish the analysis of seven BAs within 4.7 min, and the obtained LODs were at the equivalent levels with those reported methods.
Therefore, this proposed method based on d0/d3-MASC derivatization can well meet the rapid, sensitive and accurate determination of BAs from complex matrix samples.