Sensitive detection of CYFRA21-1 by a controlled release sensor based on personal glucose meter

A controlled release immunosensor for the rapid detection of lung cancer tumor marker CYFRA21–1 was designed based on a personal glucose meter (PGM). Here, polyethyleneimine modified mesoporous silica nanoparticles (MSN-PEI) were used as nanocontainers to load glucose, antibody labeled gold nanoparticles (Au NPs-Ab) were used as molecular gates to block the pores of MSN-PEI. When CYFRA21–1 antigen was added into the solution, the CYFRA21–1 antigen could specifically recognize and combine with its antibody to form complex. Thereafter, the bio-gate opened and the glucose released from the pores which could be detected on the personal glucose meter. Under the optimized conditions, the proposed PGM-based immunosensor exhibited a wide linear response to CYFRA21–1 ranging from 1.3 ng/mL to 160 ng/mL, and its detection limit is 0.79 ng/mL, it opened up a new way for the biological analysis of CYFRA21–1 and other biomarkers.