TITLE:
Achieving Ultra-Low Detection Limit Using Nanofiber Labels for Rapid Disease Detection
AUTHORS:
Emmanuel Gikunoo, Adeyabeba Abera, Eyassu Woldesenbet
KEYWORDS:
Rapid Diagnostic Test Kits, Detection Limit, Carbon Nanofibers, Immunoassay, Immunoglobulin G
JOURNAL NAME:
Advances in Infectious Diseases,
Vol.4 No.4,
December
26,
2014
ABSTRACT: Early diagnosis of diseases is critical in
its effective management. Traditional disease detection methods require
specialized equipment and trained personnel. With the introduction of rapid diagnostic test kits (RDTs), disease detection has become easier and faster.
However, these RDTs have failed to compete with the specialized laboratory
equipment due to their high detection limits and false alarm rates. This
paper presents a novel method of using carbon nanofibers (CNFs) grown on glass
microballoons (NMBs) to achieve ultra-low detection limits in RDTs. The NMBs
have millions of nanosized CNFs grown on each microballoon, with each CNF
having a strong bonding affinity for antibodies. The NMBs conjugated with
secondary antibodies have therefore a significantly higher probability of
capturing minute antigen concentrations in solution. Furthermore, the dark
color formation at the capture zone makes visual disease detection possible.
Human Immunoglobulin G (IgG) was selected as the model analyte to study the
performance of NMBs using a sandwich immunoassay protocol. Ultra-low electrical
detection limit of (4 pg/ml) and rapid re- sponse (~1 minute) was achieved
using this method.