A multiplexing immunosensing platform for the simultaneous detection of snake and scorpion venoms: Towards a better management of antidote administration.

Envenomation accidents are usually diagnosed at the hospital through signs and symptoms assessment such as short breath, dizziness and vomiting, numbness, swilling, bruising, or bleeding around the affected site. However, this traditional method provides inaccurate diagnosis given the interface between snakebites and scorpion stings symptoms. Therefore, early determination of bites/stings source would help healthcare professionals select the suitable treatment for patients, thus improving envenomation management. In this study, we developed an innovative multiplexing platform based on dual immunosensors for the simultaneous determination of snake and scorpion venoms using a label-free electrochemical platform. The dual immunosensor was fabricated on graphene/gold nanoparticle modified screen-printed electrodes. The electrodes were first modified with two chemical linkers (cysteamine/phenylene diisothiocyanate) to facilitate the immobilization of the antibodies (antivenoms) through covalent binding. The proposed immunosensor was tested with different venoms that specific to six snake species and two scorpion species. The detection was undergone by monitoring the reduction peak current variation after the venom binding using square wave voltammetry, in presence of ferro/ferricyanide redox system. The dual immunosensor enabled a sensitive and selective simultaneous detection of the snake and scorpion species venoms within wide linear ranges in the limits of detection ranging from 0.057 to 0.027 μg/mL. The applicability of the venoms immunosensor has also been evaluated for the detection of snake and scorpion venoms in human serum samples showing high recovery percentages. These achievements show the great potential of our multiplexing approach for the early detection of snake or scorpion envenomation.