(130h) The Development of a Sensitive Electrochemical Method for Carotenoid Detection

Carotenoids are biological pigment molecules that are often found in fruits, vegetables, and human tissue. Humans cannot synthesize carotenoids, but they can be accumulated through diet (Fiedor & Burda, 2014). Carotenoids have been found to lower oxidative stress which can lead to a lower risk of disease and infections (Mares-perlman et al., 2002). For example, lower carotenoid levels have also been found in patients with Alzheimer’s Disease, Parkinson’s Disease, and multiple types of cancer (de Munter et al., 2015; Nolan et al., 2014). Although there is a reverse correlation between the concentration of carotenoids and risk of disease, there are still a lot of qualities of carotenoids that are unknown to scientists. Current methods to evaluate carotenoids in serum include Raman spectroscopy, high pressure liquid chromatography, and mass spectroscopy; however, all of these methods require large equipment, and therefore, not point-of-care.

We aim to develop an effective point-of-care, cheap, and sensitive carotenoid sensor; electrochemical methods are cost effective and can maintain sensitivity. Two electrochemical methods, cyclic voltammetry and electrochemical impedance spectroscopy, were used for the detection of beta-carotene and lutein (two carotenoids). Using cyclic voltammetry, we were able to calibrate our glassy carbon electrode sensor on the micro‑molar scale. Electrochemical impedance spectroscopy, which measures the surface impedance, can be a more sensitive technique if the analyte adsorbs to the surface. We successfully detected nano-molar levels using electrochemical impedance spectroscopy, increasing sensitivity 100 fold. In addition to talking about our abilities to detect carotenoids using these two techniques, we will also discuss some of the reproducibility issues and control experiments conducted.

References:

Fiedor, J., & Burda, K. (2014). Potential Role of Carotenoids as Antioxidants in Human Health and Disease. Nutrients 6, 466–488.

Mares-perlman, J.A., Millen, A.E., Ficek, T.L., & Hankinson, S.E. (2002). Symposium : Can Lutein Protect Against Chronic Disease ? The Body of Evidence to Support a Protective Role for Lutein and Zeaxanthin in Delaying Chronic Disease . Overview 1 , 2. 518–524.

de Munter, L., Maasland, D.H., van den Brandt, P.A., Kremer, B., & Schouten, L.J. (2015). Vitamin and carotenoid intake and risk of head-neck cancer subtypes in the Netherlands Cohort Study. Am. J. Clin. Nutr. 102, 420–432.

Nolan, J.M., Loskutova, E., Howard, A.N., Moran, R., Mulcahy, R., Stack, J., Bolger, M., Dennison, J., Akuffo, K.O., Owens, N., Thurnham, D.I., & Beatty, S. (2014). Macular Pigment, Visual Function, and Macular Disease among Subjects with Alzheimer’s Disease: An Exploratory Study. J. Alzheimer’s Dis. 42, 1191–1202.