Versatility and stability of melamine foam-based biosensors (f-ELISA) using antibodies, nanobodies, and peptides as sensing probes

Abstract

Macroporous three-dimensional (3D) framework structured melamine foam-based Enzyme-Linked Immunosorbent Assay (f-ELISA) biosensors were developed for rapid, reliable, sensitive, and on-site detection of trace amount of biomolecules and chemicals. Various ligands can be chemically immobilized onto the melamine foam, which brings in the possibility of working with antibodies, nanobodies, and peptides, respectively, as affinity probes for f-ELISA biosensors with improved stability. Different chemical reagents can be used to modify the foam materials, resulting in varied reactivities with antibodies, nanobodies, and peptides. As a result, the f-ELISA sensors produced from these modified foams exhibit varying levels of sensitivity and performance. This study demonstrated that the chemical reagents used for immobilizing antibodies, nanobodies, and peptides could affect the sensitivities of the f-ELISA sensors, and their storage stabilities under different temperatures varied depending on the sensing probes used, with f-ELISA sensors employing nanobodies as probes exhibiting the highest stability. This study not only showcases the versatility of the f-ELISA system but also opens new avenues for developing cost-effective, portable, and user-friendly diagnostic tools with optimized sensitivity and stability.

Keywords: Chemical reactivity; Foam-based ELISA; Immunosensor; Nanobody; Peptide; Storage stability.