Quantification of the six major α-dicarbonyl contaminants in peritoneal dialysis fluids by UHPLC/DAD/MSMS

During heat sterilization of peritoneal dialysis solutions, glucose is partially transformed into glucose degradation products (GDPs), which significantly reduce the biocompatibility of these medicinal products. Targeted α-dicarbonyl screening identified glyoxal, methylglyoxal, 3-deoxyglucosone, 3,4-dideooxyglucosone-3-ene, glucosone, and 3-deoxygalactosone as the major six GDPs with α-dicarbonyl structure. In the present study, an ultra-high-performance liquid chromatography method was developed which allows the separation of all relevant α-dicarbonyl GDPs within a run time of 15 min after derivatization with o-phenylenediamine. Hyphenated diode array detection/tandem mass spectrometry detection provides very robust quantification and, at the same time, unequivocal peak confirmation. Systematic evaluation of the derivatization process resulted in an optimal derivatization period that provided maximal derivatization yield, minimal de novo formation (uncertainty range ±5%), and maximal sample throughput. The limit of detection of the method ranged from 0.13 to 0.19 μM and the limit of quantification from 0.40 to 0.57 μM. Relative standard deviations were below 5%, and recovery rates ranged between 91% and 154%, dependent on the type and concentration of the analyte (in 87 out of 90 samples, recovery rates were 100 ± 15%). The method was then applied for the analysis of commercial peritoneal dialysis fluids (nine different product types, samples from three lots of each).