4-Methoxy-azomethine-H as a reagent for the spectrophotometric determination of boron in plants and soils Original Research Article

An effective spectrophotometric determination of boron with 4-methoxy-azomethine-H has been developed. In a buffer medium of pH 5.7, B(III) reacts with 4-methoxy-azomethine-H to form a 1 : 2 yellow complex which has a maximum absorption at 420 nm. Under the optimum conditions, Beer’s law is obeyed over the range 0–1.4 μg ml−1 B(III). The molar absorptivity is 1.05 × 104 l mol−1 cm−1. The limit of quantification, limit of detection and relative standard deviations were 15.3, 5.3 ng ml−1 and 1.4%, respectively. The interference of various ions is observed in detail. All metal ions studied can be tolerated in considerable amounts. The proposed method is advantageous over the azomethine-H spectrophotometric method in sensitivity, selectivity and stability remarkably, and it has been applied to the determination of boron in plants and soils with satisfactory results.