Paper-based chemiluminescence immunodevice with temporal controls of reagent transport technique

Abstract

A paper-based chemiluminescence (CL) immunodevice for detection of three biomarkers with the temporal controls of reagent transport technique was developed in this work. Sugar barriers were built on the paper-based chip for the controlled reagent transport technique to create programmable flow delays for the later CL detection. Different amount of sucrose which can manipulate the reagent migration rate was drawn precisely on the microchannels by a craft-cutting instrument. The paper-based immunodevice with three channels was fabricated by the cutting method. Also the localized incision protocol with one side adhesive tape and paper-folding method were adopted here to isolate the detection zone from flow channels. This simple origami step of the detection zone can eliminate possible reagent diffusion and flowing during antibody immobilization steps and numerous washings. By using the gold nanoparticles (AuNPs) as the carrier for loading multi horseradish peroxidase (HRP) labeled signal antibody, greatly enhanced sensitivity was achieved by HRP catalyzed luminol CL system. Under a sandwich immunoassay, carcinoembryonic antigen (CEA), carcinoma antigen 125 (CA125) and carbohydrate antigen 199 (CA199) were detected on the paper-based chip. A limit of detection (LOD) of 0.03ng/mL, 0.2U/mL, 0.2U/mL was demonstrated, respectively. We believe that this paper-based CL immunodevice with controlled reagent transport technique can provide a new strategy of sensitive detection of multi-biomarkers in point-of-care (POC) diagnostics field.