Fast one-step ultrasensitive detection of Toxocara canis antigens by a nanobody-based electrochemical magnetosensor

Francisco Morales-Yanez, Stanislav Trashin, Marie Hermy, Idalia Sariego, Katja Polman, Serge Muyldermans, Karolien De Wael

Research output: Contribution to journalA1: Web of Science-article

Abstract

Human toxocariasis (HT) is a cosmopolitan zoonotic disease caused by the migration of the larval stage of the roundworm Toxocara canis. Current HT diagnostic methods do not discriminate between active and past infections. Here, we present a method to quantify Toxocara excretory/secretory antigen, aiming to identify active cases of HT. High specificity is achieved by employing nanobodies (Nbs), single domain antigen binding fragments from camelid heavy chain-only antibodies. High sensitivity is obtained by the design of an electrochemical magnetosensor with an amperometric read-out. Reliable detection of TES antigen at 10 and 30 pg/mL level was demonstrated in phosphate buffered saline and serum, respectively. Moreover, the assay showed no cross-reactivity with other nematode antigens. To our knowledge, this is the most sensitive method to quantify the TES antigen so far. It also has great potential to develop point of care diagnostic systems in other conditions where high sensitivity and specificity are required.

Original languageEnglish
JournalAnalytical Chemistry
Volume91
Issue number18
Pages (from-to)11582-11588
Number of pages7
ISSN0003-2700
DOIs
Publication statusPublished - 2019

Keywords

  • SECRETORY ANTIGENS
  • ANTIBODY
  • SEROPREVALENCE
  • DIAGNOSIS
  • IMMUNOSENSOR
  • EPIDEMIOLOGY
  • INFECTIONS

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