title: Peptide-Mediated Platelet Capture at Gold Micropore Arrays.
abstract: Ordered spherical cap gold cavity arrays with 5.4, 1.6, and 0.98 μm diameter apertures were explored as capture surfaces for human blood platelets to investigate the impact of surface geometry and chemical modification on platelet capture efficiency and their potential as platforms for surface enhanced Raman spectroscopy of single platelets. The substrates were chemically modified with single-constituent self-assembled monolayers (SAM) or mixed SAMs comprised of thiol-functionalized arginine-glycine-aspartic acid (RGD, a platelet integrin target) with or without 1-octanethiol (adhesion inhibitor). As expected, platelet adhesion was promoted and inhibited at RGD and alkanethiol modified surfaces, respectively. Platelet adhesion was reversible, and binding efficiency at the peptide modified substrates correlated inversely with pore diameter. Captured platelets underwent morphological change on capture, the extent of which depended on the topology of the underlying substrate. Regioselective capture of the platelets enabled study for the first time of the surface enhanced Raman spectroscopy of single blood platelets, yielding high quality Raman spectroscopy of individual platelets at 1.6 μm diameter pore arrays. Given the medical importance of blood platelets across a range of diseases from cancer to psychiatric illness, such approaches to platelet capture may provide a useful route to Raman spectroscopy for platelet related diagnostics.
authors.affiliation: School of Chemical Sciences, Dublin City University , Dublin 9, Ireland.
authors.forename: Kellie
authors.initials: K
authors.lastname: Adamson
authors.affiliation: School of Chemical Sciences, Dublin City University , Dublin 9, Ireland.
authors.forename: Elaine
authors.initials: E
authors.lastname: Spain
authors.affiliation: School of Chemical Sciences, Dublin City University , Dublin 9, Ireland.
authors.forename: Una
authors.initials: U
authors.lastname: Prendergast
authors.affiliation: Dept. of Molecular and Cellular Therapeutics, Royal College of Surgeons in Ireland , Dublin 2, Ireland.
authors.forename: Niamh
authors.initials: N
authors.lastname: Moran
authors.affiliation: School of Chemical Sciences, Dublin City University , Dublin 9, Ireland.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Forster
authors.affiliation: School of Chemical Sciences, Dublin City University , Dublin 9, Ireland.
authors.forename: Tia E
authors.initials: TE
authors.lastname: Keyes
mesh_terms: D001792:Blood Platelets; D006046:Gold / Q000737:chemistry*; D006801:Humans; D016023:Integrins; D010455:Peptides; D010973:Platelet Adhesiveness; D016062:Porosity
chemical_list: D016023:Integrins; D010455:Peptides; D006046:Gold
keywords: RGD; blood platelet; gold microcavity array; integrin αIIbβ3; surface; surface-enhanced Raman spectroscopy; thrombin