Purity Assessment of Fumonisin B1 by Quantitative 1H NMR Spectroscopy

Fumonisin B-1 (FB1) a mycotoxin that contaminates grains and is related with liver and renal diseases. Although FB1 levels in food are currently regulated, FB1's quantitation is complicated because of its lack of volatility and UV absorbance, preventing mass balance method from being employed for purity assessment of high-purity standard. This study used quantitative nuclear magnetic resonance (qNMR) spectroscopy to assess the purity of FB1. Unlike mass balance method, qNMR is a universal and simple quantification method. Using benzoic acid as an internal standard, the purity of FB1 was determined. The measurement parameters were optimized to obtain accurate results, and H-1 NMR peak homogeneity was confirmed by analyzing impurities separated using liquid chromatography. The purity of the FB1 was 993 mg/g and expanded uncertainty (k = 2.74) was 32 mg/g (3.2%). This result will be used to the development of the certified reference material for the FB1 analysis in maize flour.