Authors

Discussion

Malaria is an infectious disease affecting several animal species that is caused by Apicomplexan Plasmodium parasite. The strain affecting humans is transmitted by infected adult female Anopheles mosquitoes through a bite. Malaria affects approximately 50% of the world’s population causing millions of deaths every year mostly in pregnant women and children under 5 years of age. Despite control efforts the disease continues to affect productivity. Methods available for malaria detection include blood film microscopy, immunochromatographic (ICT), molecular and serological tests. Blood film microscopy shows the highest sensitivity and specificity when used by trained personnel with reliable instruments and is often used to confirm ICT results. Microscopy is however time-consuming and cannot be applied as a point-of-care detection method. This work demonstrates a malaria biosensing technique that is accurate, rapid, portable, of low cost and easy to use for the detection of Pan-malaria biomarker, Parasite lactate dehydrogenase (LDH) on an amperometric immunosensor platform.  Serial dilutions of recombinant LDH were detected in PBS buffer and 100% commercial serum, then assayed for improved signal generation using gold nanoparticles. In addition, the immunoassay was conducted using 3- fold dilutions of culture medium supernatant derived from cultured Dd2^luc transgenic clone for comparison with OptiMAL-IT malaria test kit.  The immunosensor performed on sandwich assay detected malaria antigen for the first time on DuPont gold screen-printed electrodes with a signal of approximately -0.1 µA, corresponding to ~1 ng mL^-1 analytical sensitivity.  The developed immunosensor is more sensitive than the commercial dipstick assay and is recommended for field trial using whole blood samples.