Determination of eight polycyclic aromatic hydrocarbons and in pea plants (Pisum sativum L.) extracts by high performance liquid chromatography with electrochemical detection
|Original title:||Determination of eight polycyclic aromatic hydrocarbons and in pea plants (Pisum sativum L.) extracts by high performance liquid chromatography with electrochemical detection|
|Authors:||Ondřej Zítka, Petr Babula, Jiří Sochor, Marie Kummerová, Olga Kryštofová, Vojtěch Adam, Ladislav Havel, Miroslava Beklová, Jaromír Hubálek, René Kizek|
|Type:||Article in Periodical|
|Keywords:||Polycyclic aromatic hydrocarbons; high performance liquid chromatography with UV and electrochemical detection; fluoranthene; pea plants; Pisum sativum;|
In the field of plant physiology, knowledge about polycyclic aromatic hydrocarbons (PAHs), mechanisms of actions are still missing and are limited despite the fact that induction of oxidative stress by several PAHs has been demonstrated. Primarily, high performance liquid chromatography coupled with UV detector and high performance liquid chromatography coupled with electrochemical detector were optimized for detection and quantification of the following PAHs as fluoranthene, pyrene, benzo[a]pyrene, naphthalene, benzo[a]antracene, methylanthracene, triphenylene and coronene. The optimized conditions were as follows: mobile phase - A: acetic acid (50 mM) and B: methanol (100 %). Compounds were eluted by linearly increasing gradient: 0 - 6 min (70 % B), 6 - 10 min (100 % B), 10 - 13 min (100 % B), 13 - 14 min (70 % B), 14 - 20 min (70 % B). Detection was performed at 275 nm (UV detector) and at 900 mV (electrochemical detector). One analysis lasted less than 20 minutes. Detection limits were estimated as 3 S/N down to subunits of uM for HPLC-ED and down to units of uM for HPLC-UV. It clearly follows from the results obtained that HPLC-ED has for more than one order of magnitude lower detection limits compared to HPLC-UV. It can be assumed that this difference would be higher, i.e. electrochemical detector could be more sensitive, if mobile phase with lower content of organic solvents would be used. Based on the above mentioned results, HPLC-ED was used in the following experiments. To test the applicability of our method, pea plants (Pisum sativum L. cv. Zazrak) were treated with fluoranthene (FLT) in the concentrations 0, 0.1, 1.0 and 5.0 mg/l and their tissues analysed to determine applied PAHs. Optimised HPLC method enabled determination of fluoranthene transport into different plant organs - roots, stems and leaves. Hydroponically cultivated pea plants also proved as suitable model for monitoring of effect of fluoranthene on uptake and transport of important elements.