| Autor: |
Diouani MF; Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia. fethi.diouani@pasteur.tn.; Université Tunis El Manar, Tunis 1068, Tunisia. fethi.diouani@pasteur.tn., Ouerghi O; Prince Sattam Bin Abdulaziz University, Al Kahrj 11942, Saudi Arabia. o.ouerghi@psau.edu.sa.; Université Tunis El Manar, Tunis 1068, Tunisia. o.ouerghi@psau.edu.sa., Belgacem K; Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia. kamelbelgacem85@gmail.com., Sayhi M; Institut Pasteur de Tunis, LR11IPT03, Laboratory of Epidemiology and Veterinary Microbiology (LEMV), Tunis-Belvédère 1002, Tunisia. sayhimaher@ymail.com.; Université Tunis El Manar, Tunis 1068, Tunisia. sayhimaher@ymail.com., Ionescu R; The Ångström Laboratory, Division of Solid State Physics, Department of Engineering Sciences, Uppsala University, 75121 Uppsala, Sweden. radu.ionescu@angstrom.uu.se., Laouini D; Université Tunis El Manar, Tunis 1068, Tunisia. dhafer.laouini@pasteur.tn.; Institut Pasteur de Tunis, LR11IPT02, Laboratory of Transmission, Control and Immunobiology of Infections (LTCII), Tunis-Belvédère 1002, Tunisia. dhafer.laouini@pasteur.tn. |
| Abstrakt: |
Sensitive and reliable approaches targeting the detection of Leishmania are critical for effective early diagnosis and treatment of leishmaniasis. In this frame, this paper describes a rapid quantification assay to detect Leishmania parasites based on the combination of the electrocatalytic ability of gold nanoparticles (AuNPs) to act as a catalyst for the hydrogen formation reaction along with the specificity of the interaction between casein and the major surface protease of the Leishmania parasite, GP63. First, pure and casein-modified AuNPs were prepared and characterized by scanning electron microscopy and ultraviolet-visible spectroscopy. Then, casein-conjugated AuNPs were incubated with Leishsmania parasites in solution; the formed complex was collected by centrifugation, treated by acidic solution, and the pelleted AuNPs were placed on screen-printed carbon electrodes (SPCEs) and chronoamperometric measurements were carried out. Our results suggest that it is possible to detect Leishmania parasites, with a limit less than 1 parasite/mL. A linear response over a wide concentration interval, ranging from 2 × 10 -2 to 2 × 10 5 parasites/mL, was achieved. Additionally, a pretreatment of Leishmania parasites with Amphotericin B, diminished their interaction with casein. This findings and methodology are very useful for drug efficacy assessment. |
