title: Immuno-MALDI-MS in human plasma and on-chip biomarker characterizations at the femtomole level.
abstract: Immuno-SPR-MS is the combination of immuno-sensors in biochip format with mass spectrometry. This association of instrumentation allows the detection and the quantification of proteins of interest by SPR and their molecular characterization by additional MS analysis. However, two major bottlenecks must be overcome for a wide diffusion of the SPR-MS analytical platform: (i) To warrant all the potentialities of MS, an enzymatic digestion step must be developed taking into account the spot formats on the biochip and (ii) the biological relevancy of such an analytical solution requires that biosensing must be performed in complex media. In this study, we developed a procedure for the detection and the characterization at &#126;1 &#181;g/mL of the LAG3 protein spiked in human plasma. The analytical performances of this new method was established, particularly its specificity (S/N &gt; 9) and sensitivity (100% of LAG3 identification with high significant mascot score &gt;68 at the femtomole level). The collective and automated on-chip MALDI-MS imaging and analysis based on peptidic fragments opens numerous applications in the fields of proteomics and diagnosis.
authors.affiliation: Institut FEMTO-ST, Université de Franche Comté, CLIPP (Clinical-Innovation Proteomic Platform), 25044 Besançon, France. alain.rouleau@femto-st.fr
authors.forename: Alain
authors.initials: A
authors.lastname: Rouleau
authors.forename: Marven
authors.initials: M
authors.lastname: El Osta
authors.forename: Géraldine
authors.initials: G
authors.lastname: Lucchi
authors.forename: Patrick
authors.initials: P
authors.lastname: Ducoroy
authors.forename: Wilfrid
authors.initials: W
authors.lastname: Boireau
mesh_terms: D001331:Automation; D015415:Biomarkers / Q000097:blood*; D006801:Humans; D056656:Lab-On-A-Chip Devices; D057230:Limit of Detection; D015203:Reproducibility of Results; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D020349:Surface Plasmon Resonance
chemical_list: D015415:Biomarkers