Anchoring β-cyclodextrin modified lysine to polymer monolith with biotin: specific capture of plasminogen

Plasminogen (Plg) is a kind of glycoprotein which plays an important role in cell migration. The determination of Plg content can directly reflect the abnormal manifestation of fibrinolytic system dysfunctions. In the present work, lysine (Lys)-based adsorbents were prepared for the specific capture of Plg through the covalent binding of Lys with a polymer monolithic substrate. Lys was modified with β-cyclodextrin (β-CD) via a click reaction and anchored to the substrate with biotin by host-guest interaction. The biotin-Lys-CD based monolithic material was employed for the specific capture of Plg. Combining with mass spectrometry (MS) determinations, the method exhibited a low detection limit of 1.0 fmol with relative standard deviations below 10.0% for Plg. Considering the advantages of simplicity, sensitivity, and high specificity, the developed approach was successfully applied to the determination of Plg in human plasma samples and opened a gallery for testing Plg as a biomarker for the diagnosis of fibrinolytic system dysfunctions.