AbstractBACKGROUND: A voltammetric study of vitamin E (DL‐α‐tocopherol) detection using square wave stripping and cyclic voltammetry is discussed in this paper. The working sensor was made by mixing carbon nanotube powder with DNA (double‐stranded calf thymus DNA) and mineral oil. In this electrode, the anodic peak was obtained for − 0.6 V in a 0.1 mol L−1 phosphate electrolyte solution.RESULTS: Under optimized stripping conditions, analytical linear working ranges of 0.5–4.0 µg L−1 and 40.0–160.0 µg L−1 were obtained. The RSD precision was pegged at 0.105% with seven points using an 80 µg L−1 spike. The detection limit (S/N) was found to be 0.056 µg L−1 (1.30 × 10−10 mol L−1).CONCLUSION: The developed method was found to be applicable to quality control analysis in the food, pharmaceutical and other manufacturing sectors. Copyright © 2008 Society of Chemical Industry