Fluorometric and colorimetric procedues for determining residues of benomyl

Abstract

Methods for determining benomyl, methyl 1-(butylcarbamoyl) -2-benzimidazolecarbamate, residue in plant and animal tissues and in soil involve isolation of the residue by extraction with an organic solvent, purification of the extract by a liquid-liquid partitioning procedure, conversion of the residue to 2-aminobenzimidazole, and final determination by direct fluorometric measurement or colorimetric analysis following bromination. Each method has a sensitivity of 0.1 p.p.m. based on a 50-gram sample. Average recoveries of about 87% have been obtained on all samples investigated, using both the fluorometric and colorimetric methods.

Review of methodology for the determination of benzimidazole residues in biological matrices

“…Acid hydrolysis converts BEN to MBC, while basic hydrolysis converts MBC to amino-benzimidazole. Pease and Gardiner [195] extracted BEN residues from fruit and vegetable matrices using ethyl acetate. Samples were subjected to acid and basic hydrolysis prior to LLP and determination by fluorescence spectrophotometry.…”

“…Pease and Gardiner [195] determined BEN, after conversion to 2-aminobenzimidazole (2-AB), by fluorescence spectrophotometry (λex 285 nm and λem 335 nm) or by colorimetric detection at 445 nm after derivatisation with bromine. The limit of detection was less than 100 g/kg.…”

Fluorimetric determination of the fungicide benomyl after solvolysis

“…Because of the fluorescent character of benomyl and its main degradation product carbendazim (methyl 2-benzimidazolecarbamate), several fluorimetric methods have been described [9][10][11]. GLC methods for determining carbendazim have been described 1-12-15].…”

Systemic Activity of Benomyl against Fusarium Wilt of Pea and Tomato Plants

“…PEASE and GARDINER (1969) obtained about 87 % recovery of benomyl in a variety of plant and animal tissues, although it should be realized that the analytical methods used did not discriminate between benomyl and any degradation product convertible to 2-aminoben2imidazole. PEASE and GARDINER (1969) obtained about 87 % recovery of benomyl in a variety of plant and animal tissues, although it should be realized that the analytical methods used did not discriminate between benomyl and any degradation product convertible to 2-aminoben2imidazole.…”