Electrodeposited Gold Nanoparticle (AuNP)-Film as a Nanoplatform for a Label-Free Electrochemical Strongyloidiasis Immunosensor

Abstract

Strongyloidiasis is an intestinal helminth infection caused by Strongyloides stercoralis. Early detection of this infection in immunocompromised patients is crucial to avoid severe complications and fatality. Herein, we present the potential application of electrodeposited AuNP-film in developing a label-free electrochemical immunosensor for strongyloidiasis using our synthesized monoclonal antibody. Layer-upon-layer attachment of Strongyloides monoclonal recombinant antibody protein (rMAb23) onto AuNP-film was constructed, utilizing a thiol linker via a self-assembly monolayer (SAM) technique. The modified electrode was utilized to detect S. stercoralis recombinant NIE (rNIE) protein. Each successful modification step was tested in a 10 mM [Fe(CN)6]3-/4- redox couple solution utilizing cyclic voltammetric (CV) and electrochemical impedance spectroscopic (EIS) techniques. The developed immunosensor required 20 minutes of incubation with an rNIE solution. Specificity study showed no cross-reaction with three other helminth recombinant proteins. Utilizing EIS measurements for a concentration series of rNIE protein in phosphate-buffered saline, ranging from 1 µg/mL to 10 µg/mL, we obtained a detection limit of 0.182 µg/mL. The electrochemical immunosensor was also successfully used to analyze serum samples of individuals with strongyloidiasis and healthy people. The results indicate that the immunosensor might offer an excellent diagnostic capability and a rapid and sensitive antigen detection of strongyloidiasis.

Role of Defects of Carbon Nanomaterials in the Detection of Ovarian Cancer Cells in Label-Free Electrochemical Immunosensors

“…Layer-upon-layer attachment of strongyloides monoclonal recombinant antibody protein (rMAb23) onto AuNP-film was constructed, utilizing a thiol linker via a self-assembly monolayer (SAM) technique of 11 -mercaptoundecanoic acid (11-MUA). The CV was swept from −0.1 to 1.5 V vs. Ag/AgCl for 15 cycles at 100 mV s −1 [ 33 ]. MWCNT/GNPs nanocomposite electrode was produced by electrodeposition of GNPs onto the surface of MWCNT with a potential of −0.5 V for 20 s by chronoamperometry to perform selective and sensitive electrochemical detection of dengue toxin [ 34 ].…”