Investigating Membrane Morphology and Quantity of Immobilized Protein for the Development of Lateral Flow Immunoassay

Abstract

This study was aimed at gaining a quantitative understanding of the effect of protein quantity and membrane pore structure on protein immobilization. The concentration of immobilized protein was measured by staining with Ponceau S and measuring its color intensity. In this study, both membrane morphology and the quantity of deposited protein significantly influenced the quantity of protein immobilization on the membrane surface. The sharpness and intensity of the red protein spots varied depending on the membrane pore structure, indicating a dependence of protein immobilization on this factor. Membranes with smaller pores resulted in a higher color density, corresponding to enhanced protein immobilization and an increased assay sensitivity level. An increased of immobilized volume has a significant jagged outline on the protein spot but, conversely, no difference in binding capacity.

Critical Comparison between Large and Mini Vertical Flow Immunoassay Platforms for Yersinia Pestis Detection

“…First, each VFI prototype was constructed using 0.1 μm pore size NC membranes, as the signal intensity can be enhanced with this relatively small pore size. The reasoning for this is that a smaller pore NC membrane has a larger surface area for Ag–Ab binding than a larger pore. , Indeed, our previous studies also confirmed that the 0.1 μm pore size enhanced the signal intensity approximately twofold relative to a 5 μm pore size . Previously, we built a theoretical model to simulate the antigen–antibody binding process inside the nitrocellulose membrane to identify the suitable membrane pore size and sample flow rate to improve the detection sensitivity.…”

Morphological characteristics of polymeric nylon‐6 film as biological recognition interface for electrochemical immunosensor application

“…The protein adsorptive value increases with the increase of polymer concentration. Thin film with higher polymer content leads to a better protein‐polymer binding affinity, due to the electrostatic interaction . Therefore, the highest protein binding was observed at 1359 ± 101.07 μg cm −3 , which was prepared by using 28 wt % of nylon polymer, whereas, only 994 ± 47.05 μg cm −3 protein binding was observed for nylon film with 16 wt % of polymer (N‐16 film).…”