TY  - CONF
AU  - Đurović, A.
AU  - Stojanović, Z.
AU  - Kravić, S.
AU  - Suturović, Z.
AU  - Richtera, I
AU  - Bytešníková, Z.
AU  - Grahovac, Nada
PY  - 2019
UR  - http://fiver.ifvcns.rs/handle/123456789/3693
C3  - International Conference on Chemical Sensors “Mátrafüred 2019”, Visegrád, Hungary
T1  - Application of the modified carbon paste electrodes for determination of flavonoids
SP  - 93
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3693
ER  - 

@conference{
author = "Đurović, A. and Stojanović, Z. and Kravić, S. and Suturović, Z. and Richtera, I and Bytešníková, Z. and Grahovac, Nada",
year = "2019",
journal = "International Conference on Chemical Sensors “Mátrafüred 2019”, Visegrád, Hungary",
title = "Application of the modified carbon paste electrodes for determination of flavonoids",
pages = "93",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3693"
}

Đurović, A., Stojanović, Z., Kravić, S., Suturović, Z., Richtera, I., Bytešníková, Z.,& Grahovac, N.. (2019). Application of the modified carbon paste electrodes for determination of flavonoids. in International Conference on Chemical Sensors “Mátrafüred 2019”, Visegrád, Hungary, 93.
https://hdl.handle.net/21.15107/rcub_fiver_3693

Đurović A, Stojanović Z, Kravić S, Suturović Z, Richtera I, Bytešníková Z, Grahovac N. Application of the modified carbon paste electrodes for determination of flavonoids. in International Conference on Chemical Sensors “Mátrafüred 2019”, Visegrád, Hungary. 2019;:93.
https://hdl.handle.net/21.15107/rcub_fiver_3693 .

Đurović, A., Stojanović, Z., Kravić, S., Suturović, Z., Richtera, I, Bytešníková, Z., Grahovac, Nada, "Application of the modified carbon paste electrodes for determination of flavonoids" in International Conference on Chemical Sensors “Mátrafüred 2019”, Visegrád, Hungary (2019):93,
https://hdl.handle.net/21.15107/rcub_fiver_3693 .

TY  - CONF
AU  - Stojanović, Z.
AU  - Đurović, A.
AU  - Kravić, S.
AU  - Suturović, Z.
AU  - Brezo, T.
AU  - Richtera, I
AU  - Bytešníková, Z
AU  - Grahovac, Nada
PY  - 2019
UR  - http://fiver.ifvcns.rs/handle/123456789/3704
AB  - Catechin is a flavonoid compound with polyphenolic structure naturally occurring in plants, fruits, tea, red
wine and cacao products. Many beneficial effects are associated with catechin consumption such as
antioxidant, anticarcinogenic, anti-inflammatory, antiatherogenic, antibacterial and antiviral activity.
Determination of catechin is typically based on the use of high-performance liquid chromatography, but also
methods such as spectrophotometry and capillary electrophoresis are reported.
In this work we investigated the use of different modifications of a carbon paste electrode (CPE) for
voltammetric determination of catechin. The reason for introducing a modifier into the carbon paste was to
increase the sensitivity of the voltammeircic techniques, due to the catalytic effect of the modifier on the
electrode processes. Multi-walled carbon nanotubes (MWCNTs), antimony(Ill) oxide and bismuth
nanoparticles are investigated as bulk modifiers for preparation of CPE with concentration of 5% (w/w).
Electroanalytical measurements are performed in 0.1 M phosphate buffer pH 7.0 using cyclic voltammetry
and square wave voltammetry, in the concentration range from 1 to 20 mg/dm* of catechin.
Two oxidation peaks of catechin are observed for all studied modified CPEs and bare CPE, with significantly
higher intensity of the first peak. The results also showed improvement of sensitivity by using the modified
CPEs in comparison to unmodified CPE. The application of MWCNTs as a modifier contributed to the
highest sensitivity for catechin determination in relation to the other modifiers. These preliminary results
show that MWCNTs modified CPE can be used as a very sensitive sensor for catechin determination in real
samples.
PB  - Novi Sad : Univerzitet u Novom Sadu, Tehnološki fakultet
C3  - Book of Proceedings, 21st Danube-Kris-Mures-Tisza (DKMT) Euroregional Conference on Environment and Health, University of Novi Sad, Faculty of Technology, Novi Sad, Serbia.
T1  - Application of the modified carbon paste electrodes for determination of catechin
EP  - 129
SP  - 126
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3704
ER  - 

@conference{
author = "Stojanović, Z. and Đurović, A. and Kravić, S. and Suturović, Z. and Brezo, T. and Richtera, I and Bytešníková, Z and Grahovac, Nada",
year = "2019",
abstract = "Catechin is a flavonoid compound with polyphenolic structure naturally occurring in plants, fruits, tea, red
wine and cacao products. Many beneficial effects are associated with catechin consumption such as
antioxidant, anticarcinogenic, anti-inflammatory, antiatherogenic, antibacterial and antiviral activity.
Determination of catechin is typically based on the use of high-performance liquid chromatography, but also
methods such as spectrophotometry and capillary electrophoresis are reported.
In this work we investigated the use of different modifications of a carbon paste electrode (CPE) for
voltammetric determination of catechin. The reason for introducing a modifier into the carbon paste was to
increase the sensitivity of the voltammeircic techniques, due to the catalytic effect of the modifier on the
electrode processes. Multi-walled carbon nanotubes (MWCNTs), antimony(Ill) oxide and bismuth
nanoparticles are investigated as bulk modifiers for preparation of CPE with concentration of 5% (w/w).
Electroanalytical measurements are performed in 0.1 M phosphate buffer pH 7.0 using cyclic voltammetry
and square wave voltammetry, in the concentration range from 1 to 20 mg/dm* of catechin.
Two oxidation peaks of catechin are observed for all studied modified CPEs and bare CPE, with significantly
higher intensity of the first peak. The results also showed improvement of sensitivity by using the modified
CPEs in comparison to unmodified CPE. The application of MWCNTs as a modifier contributed to the
highest sensitivity for catechin determination in relation to the other modifiers. These preliminary results
show that MWCNTs modified CPE can be used as a very sensitive sensor for catechin determination in real
samples.",
publisher = "Novi Sad : Univerzitet u Novom Sadu, Tehnološki fakultet",
journal = "Book of Proceedings, 21st Danube-Kris-Mures-Tisza (DKMT) Euroregional Conference on Environment and Health, University of Novi Sad, Faculty of Technology, Novi Sad, Serbia.",
title = "Application of the modified carbon paste electrodes for determination of catechin",
pages = "129-126",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3704"
}

Stojanović, Z., Đurović, A., Kravić, S., Suturović, Z., Brezo, T., Richtera, I., Bytešníková, Z.,& Grahovac, N.. (2019). Application of the modified carbon paste electrodes for determination of catechin. in Book of Proceedings, 21st Danube-Kris-Mures-Tisza (DKMT) Euroregional Conference on Environment and Health, University of Novi Sad, Faculty of Technology, Novi Sad, Serbia.
Novi Sad : Univerzitet u Novom Sadu, Tehnološki fakultet., 126-129.
https://hdl.handle.net/21.15107/rcub_fiver_3704

Stojanović Z, Đurović A, Kravić S, Suturović Z, Brezo T, Richtera I, Bytešníková Z, Grahovac N. Application of the modified carbon paste electrodes for determination of catechin. in Book of Proceedings, 21st Danube-Kris-Mures-Tisza (DKMT) Euroregional Conference on Environment and Health, University of Novi Sad, Faculty of Technology, Novi Sad, Serbia.. 2019;:126-129.
https://hdl.handle.net/21.15107/rcub_fiver_3704 .

Stojanović, Z., Đurović, A., Kravić, S., Suturović, Z., Brezo, T., Richtera, I, Bytešníková, Z, Grahovac, Nada, "Application of the modified carbon paste electrodes for determination of catechin" in Book of Proceedings, 21st Danube-Kris-Mures-Tisza (DKMT) Euroregional Conference on Environment and Health, University of Novi Sad, Faculty of Technology, Novi Sad, Serbia. (2019):126-129,
https://hdl.handle.net/21.15107/rcub_fiver_3704 .

TY  - CONF
AU  - Đurović, A.
AU  - Stojanović, Z.
AU  - Kravić, S.
AU  - Suturović, Z.
AU  - Grahovac, Nada
PY  - 2017
UR  - http://fiver.ifvcns.rs/handle/123456789/3687
AB  - The most important experimental parameters were investigated for chronopotentiometric
determination of imidacloprid using thin film antimony electrode as a working electrode. The
film of antimony was ex-sifu plated on the glassy carbon electrode. Britton-Robinson buffer
pH 10 was used as an optimal supporting electrolyte, where imidacloprid provided a well
define and reproductive reduction signal at the potential of -1100 mV (vs. Ag/AgCl, 3.5
mol/dm’* KCI). Based on the height and reproducibility of the analytical signal, initial potential
of -0.51 V was accepted as optimal, while selected optimal ranges of reduction current were
from -5 pA to -14.4 pA, and from -4.6 pA to -18.2 pA, for concentrations of 2 mg/dm” and 10
mg/dm°*, respectively. It was determined that analytical signal of imidacloprid decreased
exponentially with more negative values of reduction current. Before application of this
method to environmental samples. additional experiments related to method validation are
necessary.
PB  - Szeged : University of Szeged, Department of Inorganic and Analytical Chemistry
C3  - 23rd International Symposium on Analytical and Environmental Problems, Szeged, Hungary
T1  - Antimony film electrode for chronopotentiometric determination of insecticide imidacloprid
EP  - 164
SP  - 160
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3687
ER  - 

@conference{
author = "Đurović, A. and Stojanović, Z. and Kravić, S. and Suturović, Z. and Grahovac, Nada",
year = "2017",
abstract = "The most important experimental parameters were investigated for chronopotentiometric
determination of imidacloprid using thin film antimony electrode as a working electrode. The
film of antimony was ex-sifu plated on the glassy carbon electrode. Britton-Robinson buffer
pH 10 was used as an optimal supporting electrolyte, where imidacloprid provided a well
define and reproductive reduction signal at the potential of -1100 mV (vs. Ag/AgCl, 3.5
mol/dm’* KCI). Based on the height and reproducibility of the analytical signal, initial potential
of -0.51 V was accepted as optimal, while selected optimal ranges of reduction current were
from -5 pA to -14.4 pA, and from -4.6 pA to -18.2 pA, for concentrations of 2 mg/dm” and 10
mg/dm°*, respectively. It was determined that analytical signal of imidacloprid decreased
exponentially with more negative values of reduction current. Before application of this
method to environmental samples. additional experiments related to method validation are
necessary.",
publisher = "Szeged : University of Szeged, Department of Inorganic and Analytical Chemistry",
journal = "23rd International Symposium on Analytical and Environmental Problems, Szeged, Hungary",
title = "Antimony film electrode for chronopotentiometric determination of insecticide imidacloprid",
pages = "164-160",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3687"
}

Đurović, A., Stojanović, Z., Kravić, S., Suturović, Z.,& Grahovac, N.. (2017). Antimony film electrode for chronopotentiometric determination of insecticide imidacloprid. in 23rd International Symposium on Analytical and Environmental Problems, Szeged, Hungary
Szeged : University of Szeged, Department of Inorganic and Analytical Chemistry., 160-164.
https://hdl.handle.net/21.15107/rcub_fiver_3687

Đurović A, Stojanović Z, Kravić S, Suturović Z, Grahovac N. Antimony film electrode for chronopotentiometric determination of insecticide imidacloprid. in 23rd International Symposium on Analytical and Environmental Problems, Szeged, Hungary. 2017;:160-164.
https://hdl.handle.net/21.15107/rcub_fiver_3687 .

Đurović, A., Stojanović, Z., Kravić, S., Suturović, Z., Grahovac, Nada, "Antimony film electrode for chronopotentiometric determination of insecticide imidacloprid" in 23rd International Symposium on Analytical and Environmental Problems, Szeged, Hungary (2017):160-164,
https://hdl.handle.net/21.15107/rcub_fiver_3687 .

TY  - CONF
AU  - Đurović, A.
AU  - Stojanović, Z.
AU  - Kravić, S.
AU  - Suturović, Z.
AU  - Brezo, T.
AU  - Grahovac, Nada
PY  - 2017
UR  - http://fiver.ifvcns.rs/handle/123456789/3701
AB  - This paper describes chronopotentiontetrit method for determination of herbicide metamitron tising thin film  mercury electrode and glassy carbon electrode as working electrodes. At both e working electrodes one well defined reductive peak appeared im Britton-Robinson butler.
C3  - The International Conference on Electrochemical Sensors “Mátrafüred'17”, Hungary
T1  - Simple and rapid method for chronopotentiometric determination of metamitron in water samples and pesticide formulations
EP  - 16
SP  - 11
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3701
ER  - 

@conference{
author = "Đurović, A. and Stojanović, Z. and Kravić, S. and Suturović, Z. and Brezo, T. and Grahovac, Nada",
year = "2017",
abstract = "This paper describes chronopotentiontetrit method for determination of herbicide metamitron tising thin film  mercury electrode and glassy carbon electrode as working electrodes. At both e working electrodes one well defined reductive peak appeared im Britton-Robinson butler.",
journal = "The International Conference on Electrochemical Sensors “Mátrafüred'17”, Hungary",
title = "Simple and rapid method for chronopotentiometric determination of metamitron in water samples and pesticide formulations",
pages = "16-11",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3701"
}

Đurović, A., Stojanović, Z., Kravić, S., Suturović, Z., Brezo, T.,& Grahovac, N.. (2017). Simple and rapid method for chronopotentiometric determination of metamitron in water samples and pesticide formulations. in The International Conference on Electrochemical Sensors “Mátrafüred'17”, Hungary, 11-16.
https://hdl.handle.net/21.15107/rcub_fiver_3701

Đurović A, Stojanović Z, Kravić S, Suturović Z, Brezo T, Grahovac N. Simple and rapid method for chronopotentiometric determination of metamitron in water samples and pesticide formulations. in The International Conference on Electrochemical Sensors “Mátrafüred'17”, Hungary. 2017;:11-16.
https://hdl.handle.net/21.15107/rcub_fiver_3701 .

Đurović, A., Stojanović, Z., Kravić, S., Suturović, Z., Brezo, T., Grahovac, Nada, "Simple and rapid method for chronopotentiometric determination of metamitron in water samples and pesticide formulations" in The International Conference on Electrochemical Sensors “Mátrafüred'17”, Hungary (2017):11-16,
https://hdl.handle.net/21.15107/rcub_fiver_3701 .

TY  - CONF
AU  - Grahovac, Nada
AU  - Suturović, Z.
AU  - Kondić-Špika, Ankica
AU  - Sekulić, Petar
AU  - Lazić, Sanja
AU  - Šunjka, Dragana
AU  - Jakšić, Snežana
PY  - 2013
UR  - http://fiver.ifvcns.rs/handle/123456789/3305
AB  - Pesticides having different structures and biological activities are widely used for
agricultural and non-agricultural purposes. Due to their widespread use, pesticides neeq
to be determined in various environmental matrices, A wide range of analytical
techniques have been developed in order to identify the organic contaminants often
present at trace levels in environmental samples. The aim of this work was to develop a
reliable, rapid, robust and cost-effective method for the determination of five sulfonylurea
herbicides (nicosulfuron, oxasulfuron, tribenuron methyl, triasulfuron and tritosulfuron) +
spiked river water samples. The samples were diluted with 0 5% acetic acid (1:1) an
purified by solid-phase extraction (SPE) on Oasis MAX cartridges. After the cartridges
were sequentially washed with water, methanol, ethyl acetate, and acetonitrile, they were
eluted with 0.1% formic acid in acetonitrile. Elutes were evaporated to dryness and
reconstituted in acetonitrile. The purified extracts were analyzed by reversed-phase highperformance liquid chromatography with diode-array detection (HPLC-DAD) system. The
best separation was achieved on a Zorbax Eclipse XDB-Cis (50mm x 4.6mm x 1.8m)
analytical column with gradient elution at a flow rate of 1 mL/min. The analyte was
monitored at 230 nm. The linearity of calibration curve within the tested concentration
range exhibited correlation coefficients (r) higher than 0.998. The accuracy of the
method was acceptable since the average recoveries measured at two fortification levels
were in the range of 92.5-97.5% (n=3). The precision of the developed procedure
expressed as the relative standard deviations (RSDs) were lower than 4.76% in all cases
The repeatability of the retention time and peak area was checked by injecting standard
solution ten times. The relative standard deviation of the retention time and the peak area
was found to be less than 0.2% and 0 6%, respectively. The method was also validated
by analyzing freshly spiked river water samples The proposed analytical method might
be successfully applied in monitoring of sulfonylurea herbicides (nicosulfuron,
oxasulfuron, tribenuron methyl, triasulfuron and tritosulfuron) in surface water and
groundwater samples
PB  - Athens : University of the Aegean
C3  - Proceedings, 13th International Conference on Environmental Science and Technology (CEST2013), 5-7 September 2013, Athens
T1  - Analytical method validation for the determination of sulfonylurea herbicides in water samples by solid-phase extraction and HPLC with diode-array detection.
EP  - 8
SP  - 1
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3305
ER  - 

@conference{
author = "Grahovac, Nada and Suturović, Z. and Kondić-Špika, Ankica and Sekulić, Petar and Lazić, Sanja and Šunjka, Dragana and Jakšić, Snežana",
year = "2013",
abstract = "Pesticides having different structures and biological activities are widely used for
agricultural and non-agricultural purposes. Due to their widespread use, pesticides neeq
to be determined in various environmental matrices, A wide range of analytical
techniques have been developed in order to identify the organic contaminants often
present at trace levels in environmental samples. The aim of this work was to develop a
reliable, rapid, robust and cost-effective method for the determination of five sulfonylurea
herbicides (nicosulfuron, oxasulfuron, tribenuron methyl, triasulfuron and tritosulfuron) +
spiked river water samples. The samples were diluted with 0 5% acetic acid (1:1) an
purified by solid-phase extraction (SPE) on Oasis MAX cartridges. After the cartridges
were sequentially washed with water, methanol, ethyl acetate, and acetonitrile, they were
eluted with 0.1% formic acid in acetonitrile. Elutes were evaporated to dryness and
reconstituted in acetonitrile. The purified extracts were analyzed by reversed-phase highperformance liquid chromatography with diode-array detection (HPLC-DAD) system. The
best separation was achieved on a Zorbax Eclipse XDB-Cis (50mm x 4.6mm x 1.8m)
analytical column with gradient elution at a flow rate of 1 mL/min. The analyte was
monitored at 230 nm. The linearity of calibration curve within the tested concentration
range exhibited correlation coefficients (r) higher than 0.998. The accuracy of the
method was acceptable since the average recoveries measured at two fortification levels
were in the range of 92.5-97.5% (n=3). The precision of the developed procedure
expressed as the relative standard deviations (RSDs) were lower than 4.76% in all cases
The repeatability of the retention time and peak area was checked by injecting standard
solution ten times. The relative standard deviation of the retention time and the peak area
was found to be less than 0.2% and 0 6%, respectively. The method was also validated
by analyzing freshly spiked river water samples The proposed analytical method might
be successfully applied in monitoring of sulfonylurea herbicides (nicosulfuron,
oxasulfuron, tribenuron methyl, triasulfuron and tritosulfuron) in surface water and
groundwater samples",
publisher = "Athens : University of the Aegean",
journal = "Proceedings, 13th International Conference on Environmental Science and Technology (CEST2013), 5-7 September 2013, Athens",
title = "Analytical method validation for the determination of sulfonylurea herbicides in water samples by solid-phase extraction and HPLC with diode-array detection.",
pages = "8-1",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3305"
}

Grahovac, N., Suturović, Z., Kondić-Špika, A., Sekulić, P., Lazić, S., Šunjka, D.,& Jakšić, S.. (2013). Analytical method validation for the determination of sulfonylurea herbicides in water samples by solid-phase extraction and HPLC with diode-array detection.. in Proceedings, 13th International Conference on Environmental Science and Technology (CEST2013), 5-7 September 2013, Athens
Athens : University of the Aegean., 1-8.
https://hdl.handle.net/21.15107/rcub_fiver_3305

Grahovac N, Suturović Z, Kondić-Špika A, Sekulić P, Lazić S, Šunjka D, Jakšić S. Analytical method validation for the determination of sulfonylurea herbicides in water samples by solid-phase extraction and HPLC with diode-array detection.. in Proceedings, 13th International Conference on Environmental Science and Technology (CEST2013), 5-7 September 2013, Athens. 2013;:1-8.
https://hdl.handle.net/21.15107/rcub_fiver_3305 .

Grahovac, Nada, Suturović, Z., Kondić-Špika, Ankica, Sekulić, Petar, Lazić, Sanja, Šunjka, Dragana, Jakšić, Snežana, "Analytical method validation for the determination of sulfonylurea herbicides in water samples by solid-phase extraction and HPLC with diode-array detection." in Proceedings, 13th International Conference on Environmental Science and Technology (CEST2013), 5-7 September 2013, Athens (2013):1-8,
https://hdl.handle.net/21.15107/rcub_fiver_3305 .

TY  - CONF
AU  - Grahovac, Nada
AU  - Suturović, Z
AU  - Kondić-Špika, Ankica
AU  - Sekulić, P.
AU  - Lazić, S.
AU  - Šunjka, D.
AU  - Jakšić, Snežana
PY  - 2013
UR  - http://fiver.ifvcns.rs/handle/123456789/3731
AB  - Sulfonylureas represent a major advancement in global crop protection technology
and they have revolutionized weed control by introducing a unique mode of action.
These herbicides have low toxicity to mammals while they are highly toxic to plants.
The fate of sulfonylurea herbicides is directly related to their chemical structure and
mainly to the ionisation of the sulfonylurea bridge. The dissipation behavior of
nicosulfuron and oxasulfuron in soil were investigated. Soil was cored on
experimental site Rimski Sanéevi in Serbia four times (0-30 days after the spray).
The residue levels and dissipation rates of nicosulfuron and oxasulfuron in soil were
determined by liquid chromatography with diode array detection. The pesticide
formulations were applied in two different rates for nicosulfuron (50 g ai ha-1 and
100 g ai ha Nicogan 40SC) and oxasulfuron (80 g ai ha’' and 160 g ai ha’' Dynox).
The fortified recoveries were in the following range for nicosulfuron from 85.90% to
98.71% with relative standard deviations (RSDs) of 0.16—4.80% and for oxasulfuron
from 88.09% to 99.01% with relative standard deviations (RSDs) of 1.6-5.66%. The
limit of detections (LODs) for nicosulfuron and oxasulfuron in soil were 0.002 mg/kg
and 0.003 mg/kg, respectively. The dissipation of nicosulfuron and oxasulfuron
residues over the time in soil was described by the Mittag-Leffler function a*Ea,B (-
bt). Coefficients a, b, a, 8 were obtained from the experimental data, by using fitting
procedure. We got a=0.8, B=3.71, a=159.11, b=12.79 for nicosulfuron and a=0.8,
B=4.11, a=82.53, b=7.0 for oxasulfuron. The field dissipation half-life time for
nicosulfuron at the topsoil (0-30cm soil depth) was 5.2 days while for oxasulfuron
was 9.67days after application. These results could be utilized for the environmental
risks assessment and minimizing risk for contamination of natural water resources
and damage to following crops.
C3  - 8th International Symposium of Pesticides in Food and the Environment in Mediterranean Countries, Cappadocia (Urgup)/Nevsehir, Turkey
T1  - Dissipation of nicosulfuron and oxasulfuron in soil under field condition
EP  - 105
SP  - 105
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3731
ER  - 

@conference{
author = "Grahovac, Nada and Suturović, Z and Kondić-Špika, Ankica and Sekulić, P. and Lazić, S. and Šunjka, D. and Jakšić, Snežana",
year = "2013",
abstract = "Sulfonylureas represent a major advancement in global crop protection technology
and they have revolutionized weed control by introducing a unique mode of action.
These herbicides have low toxicity to mammals while they are highly toxic to plants.
The fate of sulfonylurea herbicides is directly related to their chemical structure and
mainly to the ionisation of the sulfonylurea bridge. The dissipation behavior of
nicosulfuron and oxasulfuron in soil were investigated. Soil was cored on
experimental site Rimski Sanéevi in Serbia four times (0-30 days after the spray).
The residue levels and dissipation rates of nicosulfuron and oxasulfuron in soil were
determined by liquid chromatography with diode array detection. The pesticide
formulations were applied in two different rates for nicosulfuron (50 g ai ha-1 and
100 g ai ha Nicogan 40SC) and oxasulfuron (80 g ai ha’' and 160 g ai ha’' Dynox).
The fortified recoveries were in the following range for nicosulfuron from 85.90% to
98.71% with relative standard deviations (RSDs) of 0.16—4.80% and for oxasulfuron
from 88.09% to 99.01% with relative standard deviations (RSDs) of 1.6-5.66%. The
limit of detections (LODs) for nicosulfuron and oxasulfuron in soil were 0.002 mg/kg
and 0.003 mg/kg, respectively. The dissipation of nicosulfuron and oxasulfuron
residues over the time in soil was described by the Mittag-Leffler function a*Ea,B (-
bt). Coefficients a, b, a, 8 were obtained from the experimental data, by using fitting
procedure. We got a=0.8, B=3.71, a=159.11, b=12.79 for nicosulfuron and a=0.8,
B=4.11, a=82.53, b=7.0 for oxasulfuron. The field dissipation half-life time for
nicosulfuron at the topsoil (0-30cm soil depth) was 5.2 days while for oxasulfuron
was 9.67days after application. These results could be utilized for the environmental
risks assessment and minimizing risk for contamination of natural water resources
and damage to following crops.",
journal = "8th International Symposium of Pesticides in Food and the Environment in Mediterranean Countries, Cappadocia (Urgup)/Nevsehir, Turkey",
title = "Dissipation of nicosulfuron and oxasulfuron in soil under field condition",
pages = "105-105",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3731"
}

Grahovac, N., Suturović, Z., Kondić-Špika, A., Sekulić, P., Lazić, S., Šunjka, D.,& Jakšić, S.. (2013). Dissipation of nicosulfuron and oxasulfuron in soil under field condition. in 8th International Symposium of Pesticides in Food and the Environment in Mediterranean Countries, Cappadocia (Urgup)/Nevsehir, Turkey, 105-105.
https://hdl.handle.net/21.15107/rcub_fiver_3731

Grahovac N, Suturović Z, Kondić-Špika A, Sekulić P, Lazić S, Šunjka D, Jakšić S. Dissipation of nicosulfuron and oxasulfuron in soil under field condition. in 8th International Symposium of Pesticides in Food and the Environment in Mediterranean Countries, Cappadocia (Urgup)/Nevsehir, Turkey. 2013;:105-105.
https://hdl.handle.net/21.15107/rcub_fiver_3731 .

Grahovac, Nada, Suturović, Z, Kondić-Špika, Ankica, Sekulić, P., Lazić, S., Šunjka, D., Jakšić, Snežana, "Dissipation of nicosulfuron and oxasulfuron in soil under field condition" in 8th International Symposium of Pesticides in Food and the Environment in Mediterranean Countries, Cappadocia (Urgup)/Nevsehir, Turkey (2013):105-105,
https://hdl.handle.net/21.15107/rcub_fiver_3731 .

TY  - CONF
AU  - Grahovac, Nada
AU  - Kondić-Špika, Ankica
AU  - Suturović, Z.
AU  - Sekulić, P.
AU  - Šunjka, D.
AU  - Jakšić, Snežana
PY  - 2013
UR  - http://fiver.ifvcns.rs/handle/123456789/3734
AB  - Zemijište predstavlja glavni recipijent u kome se adsorbuju i razgrađuju pesticidi, koji u njega dospevaju direktnim putem, kao posledica kontrolisane primene pri suzbijanju korova. Nikosulfuron je selektivni sistematični herbicid, apsorbuje se listom i korenom, relativno brzo se prenosi do meristemskih tkiva. Ovaj herbicid inhibira sintezu acetolaktat sintetazu (ALS), ključni enizim koji učestvuje u biosintezi amino-kiselina sa razgranatim alifatičnim nizom (valin, leucin i izoleucin) u biljkama i zaustavlja deobu ćelija i rast biljke. Nikosulfuron se primenjuje nakon nicanja kukuruza za suzbijanje jednogodišnjih i višegodišnjih uskolisnih i širokolisnih travnih korova. U poređenju sa tradicionalnim herbicidima koji se primenjuju u količini >1kg/ha, nikosulfuron je efikasan u malim količinama <100 g/ha. Postojanost nikosulfurona u zemljištu zavisi od pH, temperature, vlažnosti zemljišta i sadržaja organske materije u zemljištu. S porastom temperature ubrzava se razlaganje nikosulfurona, kako pod uticajem hemijskih faktora (hidroliza, oksidacija) tako i pod uticajem mikroorganizama.
PB  - Beograd : Srpsko hemijsko društvo
C3  - Knjiga izvoda, 6. Simpozijum „Hemija i zaštita životne sredine EnviroChem 2013“ Vršac, 21-24. maj 2013.
T1  - Ekstrakcija nikosulfurona iz zemljišta
EP  - 393
SP  - 392
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3734
ER  - 

@conference{
author = "Grahovac, Nada and Kondić-Špika, Ankica and Suturović, Z. and Sekulić, P. and Šunjka, D. and Jakšić, Snežana",
year = "2013",
abstract = "Zemijište predstavlja glavni recipijent u kome se adsorbuju i razgrađuju pesticidi, koji u njega dospevaju direktnim putem, kao posledica kontrolisane primene pri suzbijanju korova. Nikosulfuron je selektivni sistematični herbicid, apsorbuje se listom i korenom, relativno brzo se prenosi do meristemskih tkiva. Ovaj herbicid inhibira sintezu acetolaktat sintetazu (ALS), ključni enizim koji učestvuje u biosintezi amino-kiselina sa razgranatim alifatičnim nizom (valin, leucin i izoleucin) u biljkama i zaustavlja deobu ćelija i rast biljke. Nikosulfuron se primenjuje nakon nicanja kukuruza za suzbijanje jednogodišnjih i višegodišnjih uskolisnih i širokolisnih travnih korova. U poređenju sa tradicionalnim herbicidima koji se primenjuju u količini >1kg/ha, nikosulfuron je efikasan u malim količinama <100 g/ha. Postojanost nikosulfurona u zemljištu zavisi od pH, temperature, vlažnosti zemljišta i sadržaja organske materije u zemljištu. S porastom temperature ubrzava se razlaganje nikosulfurona, kako pod uticajem hemijskih faktora (hidroliza, oksidacija) tako i pod uticajem mikroorganizama.",
publisher = "Beograd : Srpsko hemijsko društvo",
journal = "Knjiga izvoda, 6. Simpozijum „Hemija i zaštita životne sredine EnviroChem 2013“ Vršac, 21-24. maj 2013.",
title = "Ekstrakcija nikosulfurona iz zemljišta",
pages = "393-392",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3734"
}

Grahovac, N., Kondić-Špika, A., Suturović, Z., Sekulić, P., Šunjka, D.,& Jakšić, S.. (2013). Ekstrakcija nikosulfurona iz zemljišta. in Knjiga izvoda, 6. Simpozijum „Hemija i zaštita životne sredine EnviroChem 2013“ Vršac, 21-24. maj 2013.
Beograd : Srpsko hemijsko društvo., 392-393.
https://hdl.handle.net/21.15107/rcub_fiver_3734

Grahovac N, Kondić-Špika A, Suturović Z, Sekulić P, Šunjka D, Jakšić S. Ekstrakcija nikosulfurona iz zemljišta. in Knjiga izvoda, 6. Simpozijum „Hemija i zaštita životne sredine EnviroChem 2013“ Vršac, 21-24. maj 2013.. 2013;:392-393.
https://hdl.handle.net/21.15107/rcub_fiver_3734 .

Grahovac, Nada, Kondić-Špika, Ankica, Suturović, Z., Sekulić, P., Šunjka, D., Jakšić, Snežana, "Ekstrakcija nikosulfurona iz zemljišta" in Knjiga izvoda, 6. Simpozijum „Hemija i zaštita životne sredine EnviroChem 2013“ Vršac, 21-24. maj 2013. (2013):392-393,
https://hdl.handle.net/21.15107/rcub_fiver_3734 .

TY  - CONF
AU  - Grahovac, Nada
AU  - Suturović, Z.
AU  - Sekulić, Petar
AU  - Stojanović, Z.
AU  - Šunjka, Dragana
AU  - Jakšić, Snežana
PY  - 2012
UR  - http://fiver.ifvcns.rs/handle/123456789/3336
AB  - Sulfonylurea herbicides are new class of herbicides that function by inhibiting the action of acetolactate synthase or acetohydroxyacid synthase, key enzymes in the biosynthesis of amino acids in plants. These herbicide class are applied at rates that are typically much lower than those used for the triazine or acetanilide herbicides that are most commonly used in agriculture.
Despite the beneficial impact of sulfonylurea herbicides on agricultural productivity, concern has been raised by the public and regulatory authorities regarding the potential for their adverse impact on soil and environmental quality and the productivity of sensitive crop in the following season. The presence of sulfonylurea pesticide residues in soils and the low dosage used requires the application of highly sensitive analytical techniques to detect trace
concentrations of residues in soil.
The method has been developed for confirmation and quantitation of three sulfonylurea herbicides including oxasulfuron, triasulfuron and prosulfuron in soil samples by high performance liquid chromatography (HPLC) with
photodiodes detection and chromatograms were extracted at 230 nm. Reverse phase liquid chromatography was used for the separation, identification and quantification of these compounds. Analytes were extracted from the soil samples with methanol-phosphate buffer (2:8, v/v) (pH 8) in an ultrasonic bath. The extracts were adjusted to pH 6.5 with 0.5% CH3COOH and passed, under vacuum, through a solid-phase extraction cartridge. The procedure involves a preconcentration step based on solid-phase extraction with silica-based bonded C18 cartridge and a N-vinyl-pyrrolidone polymer cartridge (Oasis HLB). The best results were obtained with Oasis HLB using 0.1% CH3COOH in acetonitrile as elution solvent. Spiked soil at 0.01-1.0 mg/kg levels was checked, Average recoveries of analytes from soil samples was in the range of 85-109% with a relative standard deviation of <4.2%. The limit of detection (LOD) of this method was in the range of 0.4 to 3.5 yg/kg. The proposed method is fast, easy to perform and could be utilized for monitoring of of three sulfonylurea herbicides including oxasulfuron, triasulfuron and prosulfuron residues in soil samples.
PB  - Beograd : Društvo za zaštitu bilja Srbije
C3  - Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade
T1  - Trace analysis of sulfonylurea herbicides in soil samples using solid phase extraction and liquid chromatography with photodiodes detection
EP  - 79
SP  - 78
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3336
ER  - 

@conference{
author = "Grahovac, Nada and Suturović, Z. and Sekulić, Petar and Stojanović, Z. and Šunjka, Dragana and Jakšić, Snežana",
year = "2012",
abstract = "Sulfonylurea herbicides are new class of herbicides that function by inhibiting the action of acetolactate synthase or acetohydroxyacid synthase, key enzymes in the biosynthesis of amino acids in plants. These herbicide class are applied at rates that are typically much lower than those used for the triazine or acetanilide herbicides that are most commonly used in agriculture.
Despite the beneficial impact of sulfonylurea herbicides on agricultural productivity, concern has been raised by the public and regulatory authorities regarding the potential for their adverse impact on soil and environmental quality and the productivity of sensitive crop in the following season. The presence of sulfonylurea pesticide residues in soils and the low dosage used requires the application of highly sensitive analytical techniques to detect trace
concentrations of residues in soil.
The method has been developed for confirmation and quantitation of three sulfonylurea herbicides including oxasulfuron, triasulfuron and prosulfuron in soil samples by high performance liquid chromatography (HPLC) with
photodiodes detection and chromatograms were extracted at 230 nm. Reverse phase liquid chromatography was used for the separation, identification and quantification of these compounds. Analytes were extracted from the soil samples with methanol-phosphate buffer (2:8, v/v) (pH 8) in an ultrasonic bath. The extracts were adjusted to pH 6.5 with 0.5% CH3COOH and passed, under vacuum, through a solid-phase extraction cartridge. The procedure involves a preconcentration step based on solid-phase extraction with silica-based bonded C18 cartridge and a N-vinyl-pyrrolidone polymer cartridge (Oasis HLB). The best results were obtained with Oasis HLB using 0.1% CH3COOH in acetonitrile as elution solvent. Spiked soil at 0.01-1.0 mg/kg levels was checked, Average recoveries of analytes from soil samples was in the range of 85-109% with a relative standard deviation of <4.2%. The limit of detection (LOD) of this method was in the range of 0.4 to 3.5 yg/kg. The proposed method is fast, easy to perform and could be utilized for monitoring of of three sulfonylurea herbicides including oxasulfuron, triasulfuron and prosulfuron residues in soil samples.",
publisher = "Beograd : Društvo za zaštitu bilja Srbije",
journal = "Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade",
title = "Trace analysis of sulfonylurea herbicides in soil samples using solid phase extraction and liquid chromatography with photodiodes detection",
pages = "79-78",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3336"
}

Grahovac, N., Suturović, Z., Sekulić, P., Stojanović, Z., Šunjka, D.,& Jakšić, S.. (2012). Trace analysis of sulfonylurea herbicides in soil samples using solid phase extraction and liquid chromatography with photodiodes detection. in Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade
Beograd : Društvo za zaštitu bilja Srbije., 78-79.
https://hdl.handle.net/21.15107/rcub_fiver_3336

Grahovac N, Suturović Z, Sekulić P, Stojanović Z, Šunjka D, Jakšić S. Trace analysis of sulfonylurea herbicides in soil samples using solid phase extraction and liquid chromatography with photodiodes detection. in Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade. 2012;:78-79.
https://hdl.handle.net/21.15107/rcub_fiver_3336 .

Grahovac, Nada, Suturović, Z., Sekulić, Petar, Stojanović, Z., Šunjka, Dragana, Jakšić, Snežana, "Trace analysis of sulfonylurea herbicides in soil samples using solid phase extraction and liquid chromatography with photodiodes detection" in Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade (2012):78-79,
https://hdl.handle.net/21.15107/rcub_fiver_3336 .

TY  - CONF
AU  - Grahovac, Nada
AU  - Suturović, Z.
AU  - Sekulić, Petar
AU  - Šunjka, Dragana
AU  - Jakšić, Snežana
PY  - 2012
UR  - http://fiver.ifvcns.rs/handle/123456789/3316
AB  - Sulfonylurea compounds are characterized by high herbicidal activity allowing
low-dose rates for the control of many grasses and broadleaf weeds in the
agriculture of crops. This feature means, however, that under persistent
conditions (e.g. high pH of soil, little rainfall and poor microbial activity)
remaining low concentrations of these analytes can still affect the growth of
susceptible plants. Hence, in order to control carry-over from one growing ~
season to the next, productive sensitive and selective methods are required for
the determination of residues of sulfonylurea herbicides In soil.
A screening method has been developed for the determination of sulfonylurea
in various types of soils. Methodology is based on the use of microwave
assisted solvent extraction (MASE) for fast and efficient extraction of the
analytes from the soils and reversed-phase liquid chromatography (LC) with
UV detection at 230 nm for the instrumental analysis of uncleaned extracts.
Four types of soils, including sand and clay with a range in organic matter
content of 1.45-4.39% and seven sulfonylurea herbicides (nicosulfuron,
tritosulfuron, tribenuron-methyl, prosulfuron, rimsulfuron, oxasulfuron,
triasulfuron) were selected as matrices and analytes, respectively. The method
developed included the selection of suitable MASE and LC—UV conditions.
MASE. conditions were established providing efficient extraction without
degradation of the analytes, furthermore selectivity can be enhanced by ~
limiting the coextraction of interferences. Selected MASE conditions, including
mixture dichloromethane-acetonitrile as the extraction solvent, provided a
complete extraction of the analytes from soil samples. Method validation was
performed by analysing freshly spiked soil samples with sulfonylurea and
samples with aged residues at levels between 20 and 50 mg/ kg. Depending
on the spiked level and the type of spiked sample recoveries were obtained
between 70—-100% with relative standard deviations between 5 and 10%.
Evaluation of the data set with principal component analysis revealed that the
parameters increase of organic matter content of the soil samples and aged
residues negatively effect the recovery of the analytes. The benefits of MASE,
shorter extraction times, reduction of solvent consumption, improved selectivity
and the possibility of processing 24 samples simultaneously, make this
technique a good alternative to conventional extraction procedures.
PB  - Beograd : Društvo za zaštitu bilja Srbije
C3  - Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade, Serbia
T1  - Microwave assisted solvent extraction and reversed phase liquid chromatography with diode array detection for screening sulfonylurea herbicides in soil samples
EP  - 76
SP  - 76
UR  - https://hdl.handle.net/21.15107/rcub_fiver_3316
ER  - 

@conference{
author = "Grahovac, Nada and Suturović, Z. and Sekulić, Petar and Šunjka, Dragana and Jakšić, Snežana",
year = "2012",
abstract = "Sulfonylurea compounds are characterized by high herbicidal activity allowing
low-dose rates for the control of many grasses and broadleaf weeds in the
agriculture of crops. This feature means, however, that under persistent
conditions (e.g. high pH of soil, little rainfall and poor microbial activity)
remaining low concentrations of these analytes can still affect the growth of
susceptible plants. Hence, in order to control carry-over from one growing ~
season to the next, productive sensitive and selective methods are required for
the determination of residues of sulfonylurea herbicides In soil.
A screening method has been developed for the determination of sulfonylurea
in various types of soils. Methodology is based on the use of microwave
assisted solvent extraction (MASE) for fast and efficient extraction of the
analytes from the soils and reversed-phase liquid chromatography (LC) with
UV detection at 230 nm for the instrumental analysis of uncleaned extracts.
Four types of soils, including sand and clay with a range in organic matter
content of 1.45-4.39% and seven sulfonylurea herbicides (nicosulfuron,
tritosulfuron, tribenuron-methyl, prosulfuron, rimsulfuron, oxasulfuron,
triasulfuron) were selected as matrices and analytes, respectively. The method
developed included the selection of suitable MASE and LC—UV conditions.
MASE. conditions were established providing efficient extraction without
degradation of the analytes, furthermore selectivity can be enhanced by ~
limiting the coextraction of interferences. Selected MASE conditions, including
mixture dichloromethane-acetonitrile as the extraction solvent, provided a
complete extraction of the analytes from soil samples. Method validation was
performed by analysing freshly spiked soil samples with sulfonylurea and
samples with aged residues at levels between 20 and 50 mg/ kg. Depending
on the spiked level and the type of spiked sample recoveries were obtained
between 70—-100% with relative standard deviations between 5 and 10%.
Evaluation of the data set with principal component analysis revealed that the
parameters increase of organic matter content of the soil samples and aged
residues negatively effect the recovery of the analytes. The benefits of MASE,
shorter extraction times, reduction of solvent consumption, improved selectivity
and the possibility of processing 24 samples simultaneously, make this
technique a good alternative to conventional extraction procedures.",
publisher = "Beograd : Društvo za zaštitu bilja Srbije",
journal = "Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade, Serbia",
title = "Microwave assisted solvent extraction and reversed phase liquid chromatography with diode array detection for screening sulfonylurea herbicides in soil samples",
pages = "76-76",
url = "https://hdl.handle.net/21.15107/rcub_fiver_3316"
}

Grahovac, N., Suturović, Z., Sekulić, P., Šunjka, D.,& Jakšić, S.. (2012). Microwave assisted solvent extraction and reversed phase liquid chromatography with diode array detection for screening sulfonylurea herbicides in soil samples. in Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade, Serbia
Beograd : Društvo za zaštitu bilja Srbije., 76-76.
https://hdl.handle.net/21.15107/rcub_fiver_3316

Grahovac N, Suturović Z, Sekulić P, Šunjka D, Jakšić S. Microwave assisted solvent extraction and reversed phase liquid chromatography with diode array detection for screening sulfonylurea herbicides in soil samples. in Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade, Serbia. 2012;:76-76.
https://hdl.handle.net/21.15107/rcub_fiver_3316 .

Grahovac, Nada, Suturović, Z., Sekulić, Petar, Šunjka, Dragana, Jakšić, Snežana, "Microwave assisted solvent extraction and reversed phase liquid chromatography with diode array detection for screening sulfonylurea herbicides in soil samples" in Book of Abstracts, Annual MGPR Meeting 2012 and International Conference on Food and Health Safety: Moving Towards a Sustainable Agriculture, 11-12 October 2012, Belgrade, Serbia (2012):76-76,
https://hdl.handle.net/21.15107/rcub_fiver_3316 .