The determination of avidin in genetically modified maize by voltammetric techniques

Quality assurance is a major issue in the food industry. The authenticity of food ingredients and their traceability are required by consumers and authorities. Plant species such as barley (<i>Hordeum vulgare</i>), rice (<i>Oryza sativa</i>), sunflower (<i>Helianthus annus</i>), wheat (<i>Triticum aestivum</i>) and maize (<i>Zea mays</i>) are very common objects of interest of genetic modification (GMO); therefore the development of specific assays for their specific detection and quantification of GMO are needed. Furthermore, the production and trade of genetically modified lines from an increasing number of plant species brings about the need for control within research, environmental risk assessment, labeling-legal, and consumers’ information purposes. Electrochemical sensors and biosensors based on modification of working electrode could be suitable tools for these purposes. Here, we report using of an avidin-modified carbon paste electrode for rapid and sensitive determination of avidin in plant extract solution and in a transgenic maize extract. The process could be used to determine avidin concentrations up to 3pM in solution and 170nM in a maize seed extract. Moreover, we applied the method to analyze different maize flours.