title: Molecularly imprinted polymers coupled to matrix assisted laser desorption ionization mass spectrometry for femtomoles detection of cardiac troponin I peptides.
abstract: Molecularly imprinted polymers (MIPs) were combined to MALDI-TOF-MS to evaluate a selective enrichment (SE) method for the determination of clinically relevant biomarkers from complex biological samples. The concept was proven with the myocardial injury marker Troponin I (cTnI). In a first part, MIP materials entailed for the recognition of cTnI epitopes (three peptides selected) were prepared and characterized in dimensions (0.7-2μm), dissociation constants (58-817 nM), kinetics of binding (5-60 min), binding capacity (ca. 1.5 µg/mg polymer), imprinting factors (3 > IF > 5) and selectivity for the peptide epitope. Then, the MIPs, incubated with cTnI peptides and spotted on the target with the DHB matrix, were assayed for the desorption of the peptides in MALDI-TOF-MS. The measured detection limit was ca. 300 femtomols. Finally, the MIP-SE MALDI-TOF-MS was tested for its ability to enrich in the cTnI peptides from a complex sample, mimic of serum (i.e. 81 peptides of digested albumin). The MIP-SE MALDI-TOF-MS successfully enriched in cTnI peptides from the complex sample proving the technique could offer a flexible platform to prepare entailed materials suitable for diagnostic purposes.
authors.affiliation: University of Verona, Department of Biotechnology, Strada Le Grazie 15, 37134, Verona, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Cenci
authors.affiliation: University of Trento, Department of Physics, Via Sommarive 14, 38123, Trento, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Anesi
authors.affiliation: University of Verona, Department of Biotechnology, Strada Le Grazie 15, 37134, Verona, Italy.
authors.forename: Mirko
authors.initials: M
authors.lastname: Busato
authors.affiliation: University of Trento, Department of Physics, Via Sommarive 14, 38123, Trento, Italy.
authors.forename: Graziano
authors.initials: G
authors.lastname: Guella
authors.affiliation: University of Verona, Department of Biotechnology, Strada Le Grazie 15, 37134, Verona, Italy.
authors.forename: Alessandra Maria
authors.initials: AM
authors.lastname: Bossi
mesh_terms: D006801:Humans; D057230:Limit of Detection; D054802:Molecular Imprinting / Q000379:methods; D011108:Polymers / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D019210:Troponin I / Q000032:analysis*
chemical_list: D011108:Polymers; D019210:Troponin I
keywords: MALDI-TOF-MS; cardiovascular injury; molecularly imprinted polymers; proteomics; target enrichment; troponin I