Abstract:
In the present paper, the voltammetric behavior of indole-3-butyric acid (IBA) is
described employing a boron-doped diamond electrode (BDDE). In acidic media, IBA
exhibited one well-developed oxidation signal. Two voltammetric methods, linear-sweep
(LSV) and differential pulse voltammetry (DPV), were optimized and low limits of
quantification obtained (0.79 μg mL−1 for LSV and 0.52 μg mL−1 for DPV). The latter
technique with optimized parameters was successfully applied to the determination of IBA
in growth stimulation formulas. Moreover, simultaneous voltammetric determination of
IBA and other auxin phytohormone, indole-3-acetic acid (IAA), employing BDDE was
also examined. Despite their similar structures, a simple method based on DPV and
derivatization of a selected part of the obtained curves was developed. It has been
proven that simultaneous determination of IBA and IAA is possible at various
concentration ratios with satisfactory results. Applicability of the proposed method was
verified by successful analysis of the growth stimulation preparation containing IBA or
a mixture of the auxins studied.
