Self-enzyme chemiluminescence immunoassay capable of rapidly diagnosing the infection of influenza A (H1N1) virus

• Published in: Talanta (Oxford) 2019-01, Vol.192, p.189-196
• Main Authors: Kyme, Hannah, Lee, Carol T., Kim, Young Teck, Lee, Ji Hoon
• Format: Article
• Language: English
• Subjects: 1,1′-Oxalyldiimidazole (ODI); 4-Methylumbelliferyl-N-acetyl-α-D-neuraminic acid (MUNANA); Chemiluminescence; Enzyme immunoassay; Influenza A virus; Nanocomposites; Neuraminidase
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2018.09.049

A highly sensitive self-enzyme immunoassay with 1,1′-oxalyldiimidazole chemiluminescence (ODI-CL) detection was developed for the first time to quantify influenza A (H1N1) virus. A specific capture antibody, capable of capturing hemagglutinin (HA) subtypes of H1N1, was immobilized on the surface of the magnetic Au-Fe3O4 nanocomposite. Neuraminidase (NA) subtype of H1N1 was acts as an enzyme in the self-enzyme immunoassay. A sample mixed with HA antibodies immobilized on the surface of magnetic Au-Fe3O4 nanocomposites was incubated for 1 h at 37 °C. After the incubation, magnetic Au-Fe3O4 nanocomposites separated with a magnetic bar were washed 3 times using phosphate buffered saline with Tween-20 (PBST). Then, 4-Methylumbelliferyl-N-acetyl-α-D-neuraminic acid (MUNANA), a fluorogenic substrate of NA, was added and incubated for 10 min to produce 4-Methylumbelliferone (4-MU) from the enzyme reaction between MUNANA and NA of H1N1. After the incubation, the solution containing 4-MU emitted bright light with the addition of ODI-CL reagents (e.g., H2O2 and ODI). The relative CL intensity of 4-MU was proportionally enhanced with the increase of H1N1. Also, the brightness and color of 4-MU light emitted from the self-enzyme immunoassay was dependent on pH. The self-enzyme immunoassay was able to analyze trace levels of influenza A (H1N1) virus with good accuracy, precision, reproducibility and excellent selectivity. The limit of detection (LOD = 3σ/slope) was as low as 0.19 U/ml. We expect that the self-enzyme immunoassay can be applied as a cost-effective and rapid method capable of selectively quantifying a specific influenza A virus such as H1N1, H3N2, and H5N1. [Display omitted] •The enzyme reaction between NA of influenza A virus and MUNANA.•Magnetic Au-Fe3O4 nanocomposites capable of immobilizing a hemagglutinin (HA) antibody of H1N1.•Self-enzyme immunoassay capable of quantifying H1N1 using the enzyme reaction of NA and MUNANA.