| Abstract: | Abstract One of the most widespread groups of pesticides are the triazine herbicides. These substances inhibit photosynthesis by blocking electron transport in plant chloroplasts. The possibility of the chloroplast D1 protein application for determination of the herbicide concentration in solution was investigated. Potentiometry and cyclic voltammetry have been selected to monitor specific interaction between the D1 protein and herbicide. It was found that membranes with well-defined structure, like Langmuir-Blongett film are more suitable for sensitive sensor construction than cross-linked membranes. After addition of atrazine, the current through these multilayers appeared to increase 5 fold. The effect was found to be fast and irreversible. It has been proposed that the toxic action of herbicides on chloroplasts, traditionally interpreted by inhibition of electron flow along the chloroplast membrane, may also be the result of the thylakoid membrane depolarization. |
