An integrated microfluidic device for rapid serodiagnosis of amebiasis

Abstract

A microfluidic device was successfully fabricated for the rapid serodiagnosis of amebiasis. A micro bead-based immunoassay was fabricated within integrated microfluidic chip to detect the antibody to Entamoeba histolytica in serum samples. In this assay, a recombinant fragment of C terminus of intermediate subunit of galactose and N-acetyl-D-galactosamine-inhibitable lectin of Entamoeba histolytica (C-Igl, aa 603-1088) has been utilized instead of the crude antigen. This device was validated with serum samples from patients with amebiasis and showed great sensitivity. The serodiagnosis can be completed within 20 min with 2 μl sample consumption. The device can be applied for the rapid and cheap diagnosis of other infectious disease, especially for the developing countries with very limited medical facilities.

Figure 1

Structure illustration of microfluidic chip.

Figure 2

(a) Structure illustration of micro column, standard valve and sieve valve; (b) photograph of the microfluidic chip.

Figure 3

ELISA reactivity of sera from patients against C-Igl. ELISA plate was coated with 100 ng per well of C-Igl. Serum samples from patients and healthy controls were used at 1:400 dilutions. The dashed line indicates the cut-off value. Data are representative of results from three independent experiments.

Figure 4

Schematic representation of the ELISA in the chip.

Figure 5

ELISA on the chip. The signals were collected by CCD of microscope. A: negative sample; B and C: positive samples.