Development of nitinol fiber chemically coated with zwitterionic polymeric ionic liquids for determination of beta-amyloids peptides in plasma samples from patients with Alzheimer's disease by direct coupling fiber-in-tube SPME-MS/MS

In this study, selective zwitterionic polymeric ionic liquid and dicationic polymeric ionic liquid monomers, namely, 1-vinyl-3-(butylsulfonate)imidazolium and 1,12-Di(3-vinylimidazolium)dodecane bromide were synthesized and polymerized (in-situ by a thermally initiated process) onto nitinol wires. The surface roughness (evaluated by AFM analysis) of the nitinol wires decreased after the in-situ polymerization. The success of in-situ polymerization was also confirmed by SEM analysis. The modified nitinol wires were packed into a PEEK tube to obtain a fiber-in-tube SPME extraction capillary. This capillary was directly coupled with tandem mass spectrometry (MS/MS) to determine amyloid β peptides (Alzheimer’s disease biomarker) in cerebrospinal fluid samples.