Comparison of RPLC and HILIC coupled with tandem mass spectrometry for the determination of ascorbic and dehydroascorbic acids in fruits

Abstract

In the present study the potential of reversed phase liquid chromatography (RPLC) and hydrophilic interaction chromatography (HILIC) methods combined with tandem mass spectrometry for the determination of L-ascorbic (L-AA) and dehydroascorbic (DHA) acids in fruit samples was investigated and compared. While both separation modes provide good retention and resolution of acids, the HILIC method is considerably stronger affected by a sample matrix. For the RPLC technique no significant matrix effect was observed in any of the 10-fold diluted extracts from fruit matrices tested. In order to avoid matrix effects in HILIC, the extracts required dilution factors of 50-100. Both methods showed acceptable accuracy for the determination of L-AA in fruits. The obtained recoveries of L-AA ranged from 86 to 105% and from 83 to 97% with RPLC and HILIC, respectively. The RPLC system provided satisfactory recoveries (84-108%) of DHA with good precision (RSD ≤ 4.7%), while in HILIC some problems emerged. HILIC was not sensitive enough to quantify DHA in apple and orange samples. In addition, DHA recoveries ranging from 114 to 135% and unacceptable precision with the RSD up to 24% were obtained for all samples with HILIC.