Protein coverage on silicon surfaces modified with amino-organic films: A study by AFM and angle-resolved XPS
Φόρτωση...
Ημερομηνία
Συγγραφείς
Awsiuk, K.
Bernasik, A.
Kitsara, M.
Budkowski, A.
Rysz, J.
Haberko, J.
Petrou, P.
Beltsios, K.
Raczkowska, J.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Elsevier
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Colloids and Surfaces B-Biointerfaces
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
An approach to determine structural features, such as surface fractional coverage F and thickness d of protein layers immobilized on silicon substrates coated with amino-organic films is presented. To demonstrate the proposed approach rabbit gamma globulins (RgG) are adsorbed from a 0.66 mu M solution onto SiO(2) and Si(3)N(4) modified with (3-aminopropyl)triethoxysilane (APTES). Atomic force microscopy data are analyzed by applying an integral geometry approach to yield average coverage values for silanized Si(3)N(4) and SiO(2) coated with RgG, F= 0.09 +/- 0.01 and 0.76 +/- 0.08, respectively. To determine the RgG thickness d from angle-resolved X-ray photoelectron spectroscopy (ARXPS), a model of amino-organic bilayer with non-homogeneous top lamellae is introduced. For an APTES layer thickness of 1.0 +/- 0.1 nm, calculated from independent ARXPS measurements, and for fractional surface RgG coverage determined from AFM analysis, this model yields d = 1.0 +/- 0.2 nm for the proteins on both silanized substrates. This value, confirmed by an evaluation (1.0 +/- 0.2 nm) from integral geometry analysis of AFM images, is lower than the RgG thickness expected for monomolecular film (similar to 4 nm). Structures visible in phase contrast AFM micrographs support the suggested sparse molecular packing in the studied RgG layers. XPS data, compared for bulk and adsorbed RgG, suggest preferential localization of oxygen- and nitrogen-containing carbon groups at silanized silicon substrates. These results demonstrate the potential of the developed AFM/ARXPS approach as a method for the evaluation of surface-protein coverage homogeneity and estimation of adsorbed proteins conformation on silane-modified silicon substrates used in bioanalytical applications. (c) 2010 Elsevier B.V. All rights reserved.
Περιγραφή
Λέξεις-κλειδιά
amino-organic bilayers, gamma globulins, silanized silicon, angle-resolved x-ray photoelectron spectroscopy, atomic force microscopy, integral geometry analysis, atomic-force microscopy, adsorption, orientation, fibronectin, patterns, binding, systems, quartz, mica
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000280274800010
http://ac.els-cdn.com/S0927776510002894/1-s2.0-S0927776510002894-main.pdf?_tid=68972767fa5e567a197f192317fd495b&acdnat=1339662490_e8bb99e5ffe8cb5e45752df7ec8b003a
http://ac.els-cdn.com/S0927776510002894/1-s2.0-S0927776510002894-main.pdf?_tid=68972767fa5e567a197f192317fd495b&acdnat=1339662490_e8bb99e5ffe8cb5e45752df7ec8b003a
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Μηχανικών Επιστήμης Υλικών