Surface Oxygen Vacancy-Rich Co3O4Nanowires as an Effective Catalyst of Luminol–H2O2Chemiluminescence for Sensitive Immunoassay

Autor: Lei, Jing, Zhang, Ling, Li, Mei, Liu, Wei, Jin, Yan, Li, Baoxin
Zdroj: Analytical Chemistry; December 2023, Vol. 95 Issue: 48 p17937-17944, 8p
Abstrakt: Oxygen vacancy is one intrinsic defect in metal oxide materials. Interestingly, we herein found that the surface oxygen vacancy can significantly enhance the catalytic activity of Co3O4nanowires in the luminol–H2O2chemiluminescence (CL) reaction. 0.1 ng/mL Co3O4nanowires containing 51.3% surface oxygen vacancies possessed ca.2.5-fold catalytic activity of free Co2+(the best metal ionic catalyst for the luminol–H2O2CL reaction). The superior catalytic efficiency is attributed to the enhanced adsorption of H2O2by surface oxygen vacancies, which in turn accelerates the cleavage of O–O bonds and generates •OH radicals. More importantly, the surface oxygen vacancy-rich Co3O4nanowires retained about 90% catalytic activity after modification with antibodies. The surface oxygen vacancy-rich Co3O4nanowires were used to label the secondary antibody, and one sandwich-type CL immunoassay of carcinoembryonic antigen was established. The detection limit was 0.3 ng/mL with a linear range of 1–10 ng/mL. This proof-of-concept work proves that surface oxygen vacancy-rich Co3O4nanowires are suitable for labeling biomolecules in CL bioanalysis and biosensing.
Databáze: Supplemental Index