Indirect Detection of Glycosidases Using Amperometry

Glycosidases are essential enzymes that cleave glycoside bonds. The presence of glycosidases have been widely used to detect pathogens, label cells/tissues, and report specific diseases. We have developed a rapid electrochemical assay to detect glycosidases. Exposure of electrochemically inactive substrates to glycosidases releases glucose, which can be measured easily using an electrochemical cell. Five different glycosidases were detected rapidly within 1 h using disposable electrodes. This assay could readily be incorporated into repurposed glucose meters to rapidly detect glycosidases, which in turn could be useful to report the presence of a pathogen or illness

Toward the Development of the Next Generation of a Rapid Diagnostic Test: Synthesis of Glycophosphatidylinositol (GPI) Analogues of Plasmodium falciparum and Immunological Characterization

A large number of proteins in malaria parasites are anchored using glycophosphatidylinositols (GPIs) with lipid tails. These GPIs are structurally distinct from human GPIs. Plasmodium falciparum GPIs have been considered as potential vaccine candidates because these molecules are involved in inducing inflammatory responses in human hosts, and natural anti-GPI antibody responses have been shown to be associated with protection against severe disease. GPIs can also be considered as targets for rapid diagnostic tests. Because isolation of native GPIs in large quantities is challenging, development of synthetic GPI molecules can facilitate further exploration of GPI molecules for diagnostics. Here, we report synthesis and immunological characterization of a panel of malaria-specific GPI analogues. A total of three GPI analogues were chemically synthesized and conjugated to a carrier protein to immunize and generate antibodies in rabbits. The rabbit immune sera showed reactivity with synthetic GPIs and native GPIs extracted from P. falciparum parasite, as determined by Luminex and ELISA methods