Journal des techniques analytiques et bioanalytiques

Abstrait

Nano Scale Potentiometric and Spectrophotometric Assays for 2,4-Dichlorophenoxyacetic Acid

El-Beshlawy MM

The aim of this work was to investigate the ability of silicate wire ion selective electrode to measure 2,4 dichlorophenoxyacetic acid (2,4-D). The slope of the electrode was 56.2 mV decade -1 in the range from 10-6 to 10-2 M with lower limit of detection 8.3 × 10-7 M. The electrodes were successfully applied to determination of 2,4-D by separate and standard addition potentiometry. The electrode was used to detect the effect of pH and temperature on 2,4-D placed on baby watercress plant grown in the clay soil and the residue after five day from addition. Leaf chlorophylls quantity measured utilize spectrophotometric or colorimetric assay following extraction of pigments of watercress by ethanol. This work was carried at 286, 440, 662 nm. Beer’s law was obeyed in the concentration range of 2.21 mg/ml:2.21 μg/ml. The limits of detection were 2.21 μg/ml.