Rapid three-dimensional biointerfaces for real-time immunoassay using hIL-18BPa as a model antigen.
With the goal of designing a rapid and affordable system of real-time immune monitoring for future diagnostic applications in sepsis, we have developed a biointerface composed of polyethyleneimine (PEI) and carboxymethylcellulose (CMC) to provide a means of prompt and facile immunoassay. Biointerface assembly is complete within 30 min, with all preparation performed and monitored within the measurement chamber of a quartz crystal microgravimetry with dissipation (QCM-D) sensor. Optimised biointerface composition, as determined by the mass of antibody immobilised, the level of antigen detection, and the amount of non-specific binding of human serum albumin, was determined to consist of a 4.0 mg/mL CMC hydrogel layer cross-linked to a 0.5 mg/mL PEI sub-layer. Tapping mode atomic force microscopy (AFM) in liquid demonstrates highly uniform and smooth surfaces using these hydrogels. Sensitivity of the biointerface for rhIL-18BPa is 400 ng/mL, with detection of 1 microg/mL achievable following 25 surface regenerations. Performance of the biointerface is verified using surface plasmon resonance (SPR), demonstrating the ability of the biointerface to be applied across platforms.
Carrigan
Shawn D
SD
Biomedical Engineering Department, McGill University, Duff Medical Building, rm 316, Montreal, Que., Canada H3A 2B4.
Scott
George
G
Tabrizian
Maryam
M
D000941:Antigens / Q000032:analysis / Q000276:immunology; D001681:Biological Assay / Q000295:instrumentation* / Q000379:methods; D020099:Coated Materials, Biocompatible / Q000032:analysis / Q000737:chemistry*; D003199:Computer Systems; D016207:Cytokines / Q000032:analysis*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006023:Glycoproteins / Q000032:analysis / Q000276:immunology; D007118:Immunoassay / Q000295:instrumentation* / Q000379:methods; D036341:Intercellular Signaling Peptides and Proteins; D008422:Materials Testing; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013499:Surface Properties; D014159:Transducers
D000941:Antigens; D020099:Coated Materials, Biocompatible; D016207:Cytokines; D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; C118370:interleukin-18 binding protein