Development of an electrochemical platform for selective Ara h1 allergen detection

Ara h1 is one of the major peanut allergens. It is considered one of the most severe, life-threatening food sensitivities since it triggers the highest frequency of severe and fatal reactions, even in trace amounts. Thus, it is extremely important to develop fast, accurate and easy-to-use analytical methods to determine Ara h1 allergen from food products that might contain traces of peanuts [1].

Electrochemical aptasensors have high specificity thanks to the affinity reaction between the DNA receptor and the analyte and have the ability to bind the target, even from complex matrices. The most critical steps in their development are represented by the immobilisation of the DNA strands and the signal generation [2].

This poster presents the preliminary results in the development of an electrochemical aptasensor for Ara h1 allergen detection. Although high porosity is beneficial for sensing, it brings specific challenges, since the properties of nanostructured materials often differ significantly from their bulk counterparts. Therefore, two approaches to manage the sensitivity and selectivity of the proposed aptasensor were examined. Both platforms used gold and platinum nanoparticles in order to increase the electrocatalytic effect of a screen-printed carbon electrode. For the first platform, chemical receptors based on single-walled carbon nanotubes and poly-anthranilic acid were synthesized. As for the second platform, graphene oxides modified with carboxylic groups were used as carboxyl groups donors with a polymer used to decrease the reactivity of the gold and platinum nanoparticles. These findings were used to investigate the immobilization of a 5’ amino and 3’ Ferrocene modified aptamer. For investigation of the aptamer selectivity, the newly developed aptasensor was tested in the presence of Ara h1. The process was monitored by DPV and analyzed the redox activity of the label to establish in-situ information on the binding process.

Acknowledgments

The authors acknowledge the financial support of the Romanian Ministry of Education and Research, CNCS-UEFISCDI, project number PN-III-P1-1.1-PD-2019-0631, within PNCDI III and the Italian Government in the framework of PRIN 2017, Prot. 2017YER72K_005

Bibliography

1. Tran, D.T. et al. Biosensors and Bioelectronics 2013, 43, 245–251,
2. Piro, B. et al. Biosensors 2016, 6.