Covalent Binding of Antibodies to Cellulose Paper Discs and Their Applications in Naked-eye Colorimetric Immunoassays.
This report presents two methods for the covalent immobilization of capture antibodies on cellulose filter paper grade No. 1 (medium-flow filter paper) discs and grade No. 113 (fast-flow filter paper) discs. These cellulose paper discs were grafted with amine functional groups through a silane coupling technique before the antibodies were immobilized on them. Periodate oxidation and glutaraldehyde cross-linking methods were used to graft capture antibodies on the cellulose paper discs. In order to ensure the maximum binding capacity of the capture antibodies to their targets after immobilization, the effects of various concentrations of sodium periodate, glutaraldehyde, and capture antibodies on the surface of the paper discs were investigated. The antibodies that were coated on the amine-functionalized cellulose paper discs through a glutaraldehyde cross-linking agent showed enhanced binding activity to the target when compared to the periodate oxidation method. IgG (in mouse reference serum) was used as a reference target in this study to test the application of covalently immobilized antibodies through glutaraldehyde. A new paper-based, enzyme-linked immunosorbent assay (ELISA) was successfully developed and validated for the detection of IgG. This method does not require equipment, and it can detect 100 ng/ml of IgG. The fast-flow filter paper was more sensitive than the medium-flow filter paper. The incubation period of this assay was short and required small sample volumes. This naked-eye, colorimetric immunoassay can be extended to detect other targets that are identified with conventional ELISA.
School of Applied Science, Temasek Polytechnic.
Yanfen
Y
Peng
University of Applied Sciences Utrecht.
Victor Van
VV
Gelder
School of Applied Science, Temasek Polytechnic; anburaj@tp.edu.sg.
Anburaj
A
Amaladoss
School of Applied Science, Temasek Polytechnic.
Kadamb Haribhai
KH
Patel
D000818:Animals; D000906:Antibodies; D002482:Cellulose; D003124:Colorimetry / Q000379:methods*; D004797:Enzyme-Linked Immunosorbent Assay; D051379:Mice; D010209:Paper
D000906:Antibodies; D002482:Cellulose