Abstract
A characteristic redox potential-time curve of the iron(II)/nitric acid autocatalytic reaction was applied to a time measurement-determination for sub-µM levels of folic acid. The determination range was 7.5 × 10-7 - 1.5 × 10-5 M, the detection limit (3 σ) was 5.9 × 10-7 M, and the relative standard deviation was 3.6% (n = 5).