Evaluation of click chemistry microarrays for immunosensing of alpha-fetoprotein (AFP)

Abstract

The level of cancer biomarkers in cells, tissues or body fluids can be used for the prediction of the presence of cancer or can even indicate the stage of the disease. Alpha-fetoprotein (AFP) is the most commonly used biomarker for early screening and diagnosis of hepatocellular carcinoma (HCC). Here, a combination of three techniques (click chemistry, the biotin–streptavidin–biotin sandwich strategy and the use of antigen–antibody interactions) were combined to implement a sensitive fluorescent immunosensor for AFP detection. Three types of functionalized glasses (dibenzocyclooctyne- (DBCO-), thiol- and epoxy-terminated surfaces) were biotinylated by employing the respective adequate click chemistry counterparts (biotin–thiol or biotin–azide for the first class, biotin–maleimide or biotin–DBCO for the second class and biotin–amine or biotin–thiol for the third class). The anti-AFP antibody was immobilized on the surfaces via a biotin–streptavidin–biotin sandwich technique. To evaluate the sensing performance of the differently prepared surfaces, fluorescently labeled AFP was spotted onto them via microchannel cantilever spotting (µCS). Based on the fluorescence measurements, the optimal microarray design was found and its sensitivity was determined.

Nanotechnology for Hepatocellular Carcinoma: From Surveillance, Diagnosis to Management

“…found that click chemistry combining with the biotin‐streptavidin‐biotin sandwich design and the antigen‐antibody interactions could realize a sensitive fluorometric immunosensor for AFP detection ( Figure ). [ 39 ] The anti‐AFP antibody was immobilized onto the surfaces of sandwich using the biotin‐streptavidin‐biotin protein fixation technique. The fluorescent labeled AFP was detected by microchannel cantilever spotting to evaluate the sensing performance based on the optimal microarray.…”

“…Reproduced with permission. [ 39 ] Copyright 2019, Beilstein Institute for the Advancement of Chemical Sciences. ii) Multifunctional ultrasound nanobubbles for HCC visualization.…”

Protein Microarray Immobilization via Epoxide Ring‐Opening by Thiol, Amine, and Azide

“…For this, molecules that have specific affinity with the protein in question (bioreceptors) should be immobilized on a surface (transducer). [29][30][31] In previous works, we prepared microarrays of dyes containing azide or thiol groups on DBCO-terminated glass surfaces [32] and dyes containing maleimide or DBCO groups on thiol-terminated glass surfaces [33] using microchannel cantilevers spotting (μCS). In order to enable even more flexible choice of immobilization chemistry, in this work, three different routes for the surface functionalization of epoxy-terminated glasses will be examined.…”

“…For this, molecules that have specific affinity with the protein in question (bioreceptors) should be immobilized on a surface (transducer). [29][30][31] In previous works, we prepared microarrays of dyes containing azide or thiol groups on DBCO-terminated glass surfaces [32] and dyes containing maleimide or DBCO groups on thiol-terminated…”

Click chemistry: An efficient tool to control the functionalization of metallic surfaces with alkyl chains possessing two reactive end groups

“…It has to be noticed that surface modification by mean of click chemistry has already been investigated in the literature. Notably, Dadfar et al has notably extensively studied thiol terminated surface modifications by comparing thiol-ene and thiolyne click reactions, [13] deposition of protein microarray via thiol, amine and azide functionalities for biosensor applications, [14] click reaction of alpha fetoprotein for immunosensing [15] and catalyst free click reaction for biomedical and biological applications. [16] The redox functional group selected in this study is ferrocene, which is extensively used for the formation of SAMs but also for its unique redox properties for various applications.…”