Photoelectrochemical immunodiagnosis of canine leishmaniasis using cadmium-sulfide-sensitized zinc oxide modified with synthetic peptides

- A photoelectroanalytical platform based on CdS/ZnO functionalized with peptides was developed.
- The resulting photoelectrochemical biosensor is the first LED light-driven device for diagnosis of canine leishmaniasis.
- This represents a new type of low-cost assay for detection of L. infantum antibodies.

A photoelectrochemical immunosensor for the detection of anti-Leishmania infantum antibodies based on zinc oxide and cadmium sulfide films electrodeposited on an ITO-coated glass slide (CdS/ZnO/ITO) has been proposed. The effects of light/dark conditions and the kinetics of CdS sensitizer regeneration were evaluated by scanning electrochemical microscopy in feedback mode. The platform was modified using two different peptides (PEP 13 and PEP 16) from two different proteins of high specificity and selectivity toward recognition of L. infantum antibodies, producing Peps/CdS/ZnO/ITO. This photoelectrochemical immunosensor provides a cheap and promising method of discriminating between positive and negative canine serum samples.