Abstract:Aim To establish a rapid and convenient cardiovascular biomarker protein one-step point-of-care testing (POCT) chip system. Methods A polyethylene glycol methyl ether methacrylate layer (PEGMEMA) with anti-nonspecific adsorption property was synthesized on the cyclic olefin copolymer(COC) sheet by photochemical reaction, and non-contact inkjet printing was performed on the modified surface to form antibody microarrays. The contact angles and grafting densities of the surface were explored with several monomer concentrations after irradiated under UV light for certain time periods. The modified surface structure was characterized by atomic force microscopy and infrared spectroscopy, and the protein adsorption on the surface before and after photochemical reaction was compared. The appropriate antibody inkjet printing concentration and adjuvant conditions were further explored. Finally immobilized antibodies and fluorescently labeled soluble antibodies of the growth-stimulated expression gene 2 protein (ST2), a biomarker of cardiovascular damage, were printed on the modified surface. Results When the PEGMEMA monomer concentration was 30% by mass and the illumination time was 4 min, the contact angle reached the minimum as 38.5°, and the grafting density was up to 68.47 μg/cm2. Atomic force microscopy and infrared spectroscopy showed that carbonyl and ether groups were successfully introduced into the surface. The amount of non-specific protein adsorption was reduced after surface grafting of PEGMEMA. The highest immobilization efficiency was obtained when the immobilized antibody concentration was 80 mg/L.Compared with polyethylene glycol (PEG) with several molecular weights, the effective binding efficiency of soluble antibody onto immobilized antibody microarray was higher when trehalose was used as an excipient. When the ST2 concentration was 10 mg/L, the binding of the soluble antibody on the immobilized antibody microarray after dissolution could be observed. Conclusion The anti-nonspecific adsorption of PEGMEMA was modified on the surface of the COC plastic sheet by photochemical reaction, and physically immobilized antibodies and the fluorescently labeled soluble antibodies were printed on the modified sheet surface, fabricated a protein chip system which is convenient to rapidly detect cardiovascular biomarkers, to advance cardiovascular precision medicine.