An aptamer-based electrochemical sensor for the quantification of the malaria biomarker lactate dehydrogenase

Malaria is one of the most deadly infectious diseases, causing the death of hundreds of thousands of patients each year. Global efforts to combat malaria necessitate the implementation of novel rapid diagnostic tests deployable at the point of care. Here, we present the development of an electrochemical aptamer-based (EAB) sensor for the quantification of the malaria biomarker Plasmodium falciparum lactate dehydrogenase (PfLDH). Specifically, we demonstrate how, through careful optical and electrochemical characterization, we re-engineered the aptamer sequence to maximize its binding-induced conformational change, the core principle of EAB sensors. We then demonstrated that our biosensor can quantify clinically relevant concentrations of PfLDH in blood in a single step and within a few minutes. Overall, we believe these results demonstrate the promising potential of EAB sensors for the diagnosis and prognosis of malaria at the point of care.