Quantification of residual EDU (N-ethyl-N′-(dimethylaminopropyl) carbodiimide (EDC) hydrolyzed urea derivative) and other residual by LC–MS/MS

Vaccine Analysis: Strategies, Principles, and Control

“…Separation can be performed using various technologies, for example by HPLC, HPAEC-PAD/PED (Lei et al 2000), GC, GC-MS , or CE (Lamb et al 2005 Polysaccharide is hydrolyzed to monosaccharide components and then the fluorescent label is added by reductive amination to the released monosaccharides. The methods depend on specific hydrolysis conditions to preserve specific structural aspects of the component monosaccharides.…”

“…Several adaptations and modifications of this method are available for quantifying both total and unconjugated PRP in conjugated Hib and combination vaccines (Lei et al 2000;. described an alternative method for the quantification of PRP based on TFA hydrolysis that resulted in the quantitative release of ribitol and ribose.…”

Carbohydrate-Based Vaccines

“…Tumor cells generally express different glycosylation patterns compared to non-tumor cells and often overexpress certain oligosaccharides called tumorassociated carbohydrate antigens (TACAs) such as the mucinrelated (O-linked) Tn antigen, Sialyl Tn, the glycosphingolipid Globo H, or the gangliosides GM2, GD2, GD3, and fucosyl GM1 [ 60 ]. Despite the fact that TACAs are self-glycans, they represent attractive targets for vaccines due to their unusually high expression by cancer cells.…”

“…Thus, CLR targeting using carbohydrate ligands is a promising approach to shape immune responses [ 63 ]. CLR-triggered responses may be diverse and strongly depend on the nature of the ligand, cross-talk with other PRRs such as TLRs and the expression pattern of CLRs on APCs [ 60 ]. The specifi city of CLRs for certain carbohydrates is defi ned by conserved amino acid motifs in the CRD.…”

“…Residual formaldehyde, from carrier protein detoxifi cation or reversion of the toxoid, is potentially present in the fi nal conjugate and there are general limits for this. Similarly, clearance of process residuals from the conjugation chemistry (such as the urea residue 1-(3-dimethylaminopropyl)-3-ethylurea derived from hydrolysis of EDAC) should be confi rmed either by direct analysis [ 60 ] or by process validation.…”