5
66
T. Mackul’ak et al.
Lachema (Brno, Czech Republic) except for the atrazine
standard (Agrovita, Ivanka pri Dunaji, Slovak Republic)
with a purity of 98%.
of atrazine in the filtrate were determined by HPLC. All
reactions were carried out under daylight.
HPLC analysis
Instrumentation
The degradation products of atrazine were analyzed by
HPLC with a PDA detector, using a reversed phase column
(GraceSmart, RP-18, length 150 mm, ID 4.6 mm). The
spectra were recorded from 190 to 900 nm, and chro-
matograms were monitored at 200, 210, 222, and 235 nm.
The temperature of the column oven was set to 25 °C. The
sample was dissolved in water and injected into the HPLC
column. Methanol:water was used as the mobile phase for
analysis, while the ratio of these two phases was gradually
changed during the analysis from 10:90 to 90:10. The flow
3
Each experiment was carried out in a 500 cm Erlenmeyer
flask. All solutions were prepared in deionized water.
Stirring of the reaction mixture was performed using
a Teflon-coated bar at approximately 300 rpm with a
magnetic stirrer (MMA, Germany). The reaction tempera-
ture was 25 °C. All pH measurements were carried out by a
digital ion pH meter (Ion Activity Meter MS-20). The
degradation products of atrazine were identified by HPLC
(
Young Lin Instruments, YL9100 HPLC system, South
3
-1
Korea) with a photodiode array detector (PDA, Young Lin
Instruments, YL9160, South Korea).
rate was 1 cm min . The injection volume was held
3
constant at 10 mm . The multi-wavelength detector can
monitor the degradation products of atrazine continuously
between 190 and 900 nm, which enables the UV and vis-
ible regions to be monitored simultaneously. The spectra
were recorded and stored in the HPLC spectrum library.
The criteria for the identification of degradation products of
atrazine were established by comparison of the retention
time and spectrum of an unknown compound with
standards.
Sample preparation: degradation of atrazine by Fenton
reaction (FeSO ꢀ7H O and H O )
4
2
2 2
The following procedure was used for the degradation of
atrazine: 10 mg of atrazine was added to an Erlenmeyer
3
3
flask (500 cm ) containing 300 cm of deionized water. To
this solution with intensive stirring the necessary amount of
FeSO ꢀ7H O and H O in the primary ratio (H O : FeS-
4
2
2
2
2 2
-
3
Acknowledgments The authors thank the Grant Agency of the
Slovak Republic (VEGA grants no. 1/0390/09, 1/0866/08, and
O = 875:500 mg dm ) were added. The reaction times
4
for these experiments were 5 min, 24, and 72 h. After 72 h,
the reaction mixture was left standing for 72 h and neu-
tralized by 20% NaOH. After filtering off the resulting
precipitate, degradation products of atrazine in the filtrate
were determined by HPLC. For all different reaction times
used, all samples for HPLC analysis were prepared by the
neutralization and filtration of the given reaction mixture.
All reactions were carried out under daylight.
1
/0182/11) for financial support.
References
1. Hesketh N, Jones NM, Tipping E (1996) Anal Chim Acta
3
27:191
. Claver A, Ormad P, Rodriguez L, Ovelleiro JL (2006) Chemo-
sphere 64:1437
. Singh N, Megharaj M, Kookana SR, Naidu R (2004) Chemo-
sphere 56:257
. Abarikwu OS, Adesiyan AC, Oyejola OT, Oyeyemi OM, Far-
ombi OE (2009) Fertil Steril 91:S8
ˇ
. Hiller E, Krascsenits Z, K u´ tnik P, Bartal M (2004) Geoch e´ mia.
Dionyz Stur, Bratislava
2
3
4
5
Sample preparation: degradation of atrazine
0
by modified Fenton reaction (Fe /H O /H SO )
2
2
2
4
To compare the efficiency of the degradation of atrazine,
the modified Fenton reaction procedure was also used:
6. Maleki N, Absalan G, Safavi A, Farjami E (2007) Anal Chim
Acta 581:37
7. Kesari R, Gupta VK (1998) Talanta 47:1085
1
0 mg of atrazine was added to an Erlenmeyer flask
3
500 cm ) containing 300 cm deionized water. To this
3
(
8
. Wulfeck-Kleier KA, Ybarra MD, Speth TF, Magnuson ML
2010) J Chromatogr A 1217:676
9. Min G, Wang S, Zhu H, Fang G, Zhang Y (2008) Sci Total
3
solution with intensive stirring 0.05 cm concentrated
H SO was added, and then approximately 3 g of activated
(
2
4
Environ 396:79
0. Ahel M, Evans KM, Fileman TW, Mantoura RFC (1992) Anal
Chim Acta 268:195
1. Zhoua Q, Xiao J, Wang W, Liu G, Shi Q, Wang J (2006) Talanta
68:1309
Fe shavings (technical shavings were cleared by soap,
washed by distilled water, activated by 20% H SO , re-
1
1
2
4
washed by deionized water, and immediately used in the
reaction). After the induction time (10 min), the necessary
3
amount of H O (0.8 cm 30% H O ) was added. The
12. Katsumata H, Kaneco S, Suzuki T, Ohta K (2006) Anal Chim
Acta 577:214
2
2
2 2
reaction time for the experiment was 24 h. Then the
reaction mixture was neutralized by 20% NaOH. After
filtering off the resulting precipitate, degradation products
1
3. Bohuss I, Boz o´ ki J, Bark a´ cs K, Z a´ ray G (2003) Microchem J
4:165
14. Tomkins BA, Ilgner RH (2002) J Chromatogr A 972:183
7
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