Performance of impedimetric biosensors based on anodically formed Ti/TiO2 electrodes
Φόρτωση...
Ημερομηνία
Συγγραφείς
Mantzila, A. G.
Prodromidis, M. I.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
WILEY-VCH Verlag
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Electroanalysis
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
The advantages and limitations of impedimetric sensors based on Ti/TiO2 architectures are described. Titanium dioxide (titania) was potentiostatically formed onto titanium electrodes of 2 mm diameter, at 10 and 30 V in 1 M H-2 SO4. The thickness of the titania layers was ellipsometrically determined to be 30 and 86 nm respectively and they are highly insulating with charge-transfer resistances in the M Omega range, as they were measured with electrochemical impedance spectroscopy under specific experimental conditions. Low voltage anodization (< 10V) results to amorphous TiO2, whereas at higher applied voltages (> 25 V), anatase is the predominant form. SEM images are indicative of quite smooth, compact coatings without any severe cracks. Titania films were further treated with sodium hydroxide to increase the population of hydroxyl groups onto the outer oxide layer. Various silanization procedures based on liquid and gas-phase anhydrous conditions were employed to produce amino-terminated surfaces. Using glutaraldehyde as a cross linker, avidin was immobilized by chemical bonding. All impedimetric measurements were performed using biotinylated dextran as the target analyte. The initial conductivity of titanium/titania electrodes, as it can be managed by means of the hydroxylation process (duration of chemical etching) as well as the silane layer are major factors affecting the performance of the resultant biosensors. Extended studies using electrochemical impedance spectroscopy provided important new insights into the mechanism of the signal transduction and the physical factors that control the nature of the measuring signal.
Περιγραφή
Λέξεις-κλειδιά
impedance sensors, electrochemical impedance spectroscopy, anodic titania layers, avidin-biotinylated dextran binding, self-assembled monolayers, impedance spectroscopy, immunosensor, films, ellipsometry, salmonella, sensor, rutile, gold
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000233155600013
http://onlinelibrary.wiley.com/store/10.1002/elan.200503306/asset/1878_ftp.pdf?v=1&t=h0dztsme&s=2effab093b1ea171eb6f3b257e64c41493ba15e3
http://onlinelibrary.wiley.com/store/10.1002/elan.200503306/asset/1878_ftp.pdf?v=1&t=h0dztsme&s=2effab093b1ea171eb6f3b257e64c41493ba15e3
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας