Ni-NTA resin-based multiplexed origami device for highly efficient sensing of allergen-specific IgE

Abstract

Food allergy diagnosis requires a highly sensitive detection of allergen-specific immunoglobulin E (sIgE) in the serum. Enzyme-linked immunosorbent assay (ELISA) is a classical method widely used for sIgE detection but had to rely on costly and time-consuming assay procedures, skilled technicians, and bulky equipment. Here, a multiplexed origami paper analytical device (moPAD) that is hexahistidine-tagged and integrated with a nitrilotriacetic acid-functionalized surface with nickel (Ni-NTA) was developed to achieve low-cost and high-efficiency immunosensing of multiple allergen-specific IgEs in serum. The major oyster allergens, Cra a 1, Cra a 2, and Cra a 4, were used to detect sIgE in human serum. The feasibility of the moPAD-based immunosensing strategy was successfully demonstrated by desirable sensitivities for multiple targets. The detection results of moPAD for 72 serum samples were 100% consistent with clinical test results, while 69 of these results showed no significant differences from ELISA results, demonstrating the accuracy and stability of this method. A fully integrated moPAD reduces detection time and achieves highly sensitive quantification using a simple smartphone-based readout. Efficient allergen modification of paper devices has great applicability in allergen component-resolved diagnostics. The implementation of moPAD can make the process of allergy diagnosis simpler for patients, physicians, and healthcare systems alike.