title: Extended-gate field-effect transistor (EG-FET) with molecularly imprinted polymer (MIP) film for selective inosine determination.
abstract: A novel recognition unit of chemical sensor for selective determination of the inosine, renal disfunction biomarker, was devised and prepared. For that purpose, inosine-templated molecularly imprinted polymer (MIP) film was deposited on an extended-gate field-effect transistor (EG-FET) signal transducing unit. The MIP film was prepared by electrochemical polymerization of bis(bithiophene) derivatives bearing cytosine and boronic acid substituents, in the presence of the inosine template and a thiophene cross-linker. After MIP film deposition, the template was removed, and was confirmed by UV-visible spectroscopy. Subsequently, the film composition was characterized by spectroscopic techniques, and its morphology and thickness were determined by AFM. The finally MIP film-coated extended-gate field-effect transistor (EG-FET) was used for signal transduction. This combination is not widely studied in the literature, despite the fact that it allows for facile integration of electrodeposited MIP film with FET transducer. The linear dynamic concentration range of the chemosensor was 0.5-50 μM with inosine detectability of 0.62 μM. The obtained detectability compares well to the levels of the inosine in body fluids which are in the range 0-2.9 µM for patients with diagnosed diabetic nephropathy, gout or hyperuricemia, and can reach 25 µM in certain cases. The imprinting factor for inosine, determined from piezomicrogravimetric experiments with use of the MIP film-coated quartz crystal resonator, was found to be 5.5. Higher selectivity for inosine with respect to common interferents was also achieved with the present molecularly engineered sensing element. The obtained analytical parameters of the devised chemosensor allow for its use for practical sample measurements.
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
authors.forename: Zofia
authors.initials: Z
authors.lastname: Iskierko
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
authors.forename: Marta
authors.initials: M
authors.lastname: Sosnowska
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland.
authors.forename: Piyush Sindhu
authors.initials: PS
authors.lastname: Sharma
authors.affiliation: Dipartimento di Scienza ed Alta Tecnologia, Università degli Studi dell'Insubria, via Valleggio, 11-22100 Como, Italy.
authors.forename: Tiziana
authors.initials: T
authors.lastname: Benincori
authors.affiliation: Department of Chemistry, University of North Texas, Denton, TX 76203-5017, USA.
authors.forename: Francis
authors.initials: F
authors.lastname: D'Souza
authors.affiliation: Institute of Physics, Polish Academy of Sciences, 32/46 Al. Lotników, 02-668 Warsaw, Poland.
authors.forename: Izabela
authors.initials: I
authors.lastname: Kaminska
authors.affiliation: Institute of Physics, Polish Academy of Sciences, 32/46 Al. Lotników, 02-668 Warsaw, Poland.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Fronc
authors.affiliation: Institute of Physical Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland. Electronic address: knoworyta@ichf.edu.pl.
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Noworyta
mesh_terms: D003217:Conductometry / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007288:Inosine / Q000032:analysis* / Q000737:chemistry; D055617:Micro-Electrical-Mechanical Systems / Q000295:instrumentation*; D008839:Microelectrodes; D054802:Molecular Imprinting / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014173:Transistors, Electronic
chemical_list: D007288:Inosine
keywords: Chemosensor; Extended-gate field-effect transistor; Inosine; Molecularly imprinted polymer; Piezomicrogravimetry