TY  - JOUR
AU  - Mehmeti, Eda
AU  - Stanković, Dalibor M.
AU  - Chaiyo, Sudkate
AU  - Zavasnik, Janez
AU  - Zagar, Kristina
AU  - Kalcher, Kurt
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1477
AB  - A reagentless third generation electrochemical glucose biosensor was fabricated based on wiring the template enzyme glucose oxidase (GOx) with graphene nanoribbons (GN) in order to create direct electron transfer between the co-factor (flavin adenine dinucleotide, FAD) and the electrode. The strategy involved: (i) isolation of the apo-enzyme by separating it from its co-enzyme; (ii) preparation of graphene nanoribbons (GN) by oxidative unzipping of multi-walled carbon nanotubes; (iii) adsorptive immobilization of GNs on the surface of a screen printed carbon electrode (SPCE); (iv) covalent attachment of FAD to the nanoribbons; (v) recombination of the apo-enzyme with the covalently bound FAD to the holoenzyme; and (vi) stabilization of the bio-layer with a thin membrane of Nafion. The biosensor (referred to as GN/FAD/apo-GOx/Nafion/SPCE) is operated at a potential of +0.475 V vs Ag/AgCl/{3 M KCl} in flow-injection mode with an oxygen-free phosphate buffer (pH 7.5) acting as a carrier. The signals are linearly proportional to the concentration of glucose in the range from 50 to 2000 mgai...L-1 with a detection limit of 20 mgai...L-1. The repeatability (10 measurements, at 1000 mgai...L-1 glucose) is +/- 1.4% and the reproducibility (5 sensors, 1000 mgai...L-1 glucose) is +/- 1.8%. The biosensor was applied to the determination of glucose in human serum.
T2  - Microchimica Acta
T1  - Wiring of glucose oxidase with graphene nanoribbons: an electrochemical third generation glucose biosensor
VL  - 184
IS  - 4
SP  - 1127
EP  - 1134
DO  - 10.1007/s00604-017-2115-5
ER  - 

@article{
author = "Mehmeti, Eda and Stanković, Dalibor M. and Chaiyo, Sudkate and Zavasnik, Janez and Zagar, Kristina and Kalcher, Kurt",
year = "2017",
abstract = "A reagentless third generation electrochemical glucose biosensor was fabricated based on wiring the template enzyme glucose oxidase (GOx) with graphene nanoribbons (GN) in order to create direct electron transfer between the co-factor (flavin adenine dinucleotide, FAD) and the electrode. The strategy involved: (i) isolation of the apo-enzyme by separating it from its co-enzyme; (ii) preparation of graphene nanoribbons (GN) by oxidative unzipping of multi-walled carbon nanotubes; (iii) adsorptive immobilization of GNs on the surface of a screen printed carbon electrode (SPCE); (iv) covalent attachment of FAD to the nanoribbons; (v) recombination of the apo-enzyme with the covalently bound FAD to the holoenzyme; and (vi) stabilization of the bio-layer with a thin membrane of Nafion. The biosensor (referred to as GN/FAD/apo-GOx/Nafion/SPCE) is operated at a potential of +0.475 V vs Ag/AgCl/{3 M KCl} in flow-injection mode with an oxygen-free phosphate buffer (pH 7.5) acting as a carrier. The signals are linearly proportional to the concentration of glucose in the range from 50 to 2000 mgai...L-1 with a detection limit of 20 mgai...L-1. The repeatability (10 measurements, at 1000 mgai...L-1 glucose) is +/- 1.4% and the reproducibility (5 sensors, 1000 mgai...L-1 glucose) is +/- 1.8%. The biosensor was applied to the determination of glucose in human serum.",
journal = "Microchimica Acta",
title = "Wiring of glucose oxidase with graphene nanoribbons: an electrochemical third generation glucose biosensor",
volume = "184",
number = "4",
pages = "1127-1134",
doi = "10.1007/s00604-017-2115-5"
}

Mehmeti, E., Stanković, D. M., Chaiyo, S., Zavasnik, J., Zagar, K.,& Kalcher, K.. (2017). Wiring of glucose oxidase with graphene nanoribbons: an electrochemical third generation glucose biosensor. in Microchimica Acta, 184(4), 1127-1134.
https://doi.org/10.1007/s00604-017-2115-5

Mehmeti E, Stanković DM, Chaiyo S, Zavasnik J, Zagar K, Kalcher K. Wiring of glucose oxidase with graphene nanoribbons: an electrochemical third generation glucose biosensor. in Microchimica Acta. 2017;184(4):1127-1134.
doi:10.1007/s00604-017-2115-5 .

Mehmeti, Eda, Stanković, Dalibor M., Chaiyo, Sudkate, Zavasnik, Janez, Zagar, Kristina, Kalcher, Kurt, "Wiring of glucose oxidase with graphene nanoribbons: an electrochemical third generation glucose biosensor" in Microchimica Acta, 184, no. 4 (2017):1127-1134,
https://doi.org/10.1007/s00604-017-2115-5 . .

TY  - JOUR
AU  - Mehmeti, Eda
AU  - Stanković, Dalibor M.
AU  - Ortner, Astrid
AU  - Zavasnik, Janez
AU  - Kalcher, Kurt
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1763
AB  - A boron-doped diamond electrode was used as an electrochemical sensor for the determination of phlorizin (aka phloridzin, phlorrhizin) using square wave voltammetry (SWV). Phlorizin (Phl) exhibited a well-defined oxidation peak at +0.9 V (versus Ag/AgCl electrode 3 M KCl) in solutions with a pH value of 6.0. Parameters such as pH value and scan rate were optimized for cyclic voltammetry as well as amplitude and frequency for SWV. The sensor gave excellent response with a wide linear dynamic range for concentrations of phlorizin from 3 to 100 mu M with a detection limit of 0.23 mu M and a good repeatability (+/- 0.9%, n = 7 measurements, c = 10 mu M). The effect of interferences by most common compounds was tested, and the method was successfully applied to the determination of the title compound in apple root extracts and urine samples with satisfactory recovery.
T2  - Food Analytical Methods
T1  - Highly Selective Electrochemical Determination of Phlorizin Using Square Wave Voltammetry at a Boron-Doped Diamond Electrode
VL  - 10
IS  - 11
SP  - 3747
EP  - 3752
DO  - 10.1007/s12161-017-0935-x
ER  - 

@article{
author = "Mehmeti, Eda and Stanković, Dalibor M. and Ortner, Astrid and Zavasnik, Janez and Kalcher, Kurt",
year = "2017",
abstract = "A boron-doped diamond electrode was used as an electrochemical sensor for the determination of phlorizin (aka phloridzin, phlorrhizin) using square wave voltammetry (SWV). Phlorizin (Phl) exhibited a well-defined oxidation peak at +0.9 V (versus Ag/AgCl electrode 3 M KCl) in solutions with a pH value of 6.0. Parameters such as pH value and scan rate were optimized for cyclic voltammetry as well as amplitude and frequency for SWV. The sensor gave excellent response with a wide linear dynamic range for concentrations of phlorizin from 3 to 100 mu M with a detection limit of 0.23 mu M and a good repeatability (+/- 0.9%, n = 7 measurements, c = 10 mu M). The effect of interferences by most common compounds was tested, and the method was successfully applied to the determination of the title compound in apple root extracts and urine samples with satisfactory recovery.",
journal = "Food Analytical Methods",
title = "Highly Selective Electrochemical Determination of Phlorizin Using Square Wave Voltammetry at a Boron-Doped Diamond Electrode",
volume = "10",
number = "11",
pages = "3747-3752",
doi = "10.1007/s12161-017-0935-x"
}

Mehmeti, E., Stanković, D. M., Ortner, A., Zavasnik, J.,& Kalcher, K.. (2017). Highly Selective Electrochemical Determination of Phlorizin Using Square Wave Voltammetry at a Boron-Doped Diamond Electrode. in Food Analytical Methods, 10(11), 3747-3752.
https://doi.org/10.1007/s12161-017-0935-x

Mehmeti E, Stanković DM, Ortner A, Zavasnik J, Kalcher K. Highly Selective Electrochemical Determination of Phlorizin Using Square Wave Voltammetry at a Boron-Doped Diamond Electrode. in Food Analytical Methods. 2017;10(11):3747-3752.
doi:10.1007/s12161-017-0935-x .

Mehmeti, Eda, Stanković, Dalibor M., Ortner, Astrid, Zavasnik, Janez, Kalcher, Kurt, "Highly Selective Electrochemical Determination of Phlorizin Using Square Wave Voltammetry at a Boron-Doped Diamond Electrode" in Food Analytical Methods, 10, no. 11 (2017):3747-3752,
https://doi.org/10.1007/s12161-017-0935-x . .