Detection of Leishmania-specific DNA and surface antigens using a combination of functionalized magnetic beads and cadmium selenite quantum dots

Leishmaniosis is a zoonotic disease that affects millions of people especially in resource-poor settings. The development of reliable diagnostic assays that do not require dedicated equipment or highly trained personnel would improve early diagnosis and effective control. For this purpose, a combination of magnetic bead and cadmium selenite quantum dot probes was applied for the detection of Leishmania-specific surface antigens (proteins) and DNA. Both analytes are isolated from the solution using magnetic bead capture probes whereas the presence of the targeted molecules is demonstrated by quantum dot detection probes. The sensitivity and specificity of this method reached 100% based on an assessment performed on 55 cultured isolates of various microbial pathogens. The low limit of detection was 3125 ng/mu l and 10(3) cells/ml for Leishmania DNA and protein, respectively. The method shows considerable potential for clinical application in human and veterinary medicine, especially in resource-poor settings. (C) 2015 Elsevier B.V. All rights reserved.