posted on 2021-01-26, 17:11authored byGuangyao Zhang, Mengjie Li, Kun Yu, Huining Chai, Shenghao Xu, Tailin Xu, Lijun Qu, Xueji Zhang
A dual-mechanism-driven ratiometric
electrochemiluminescent (ECL)
biosensor was developed for the ultrasensitive detection of protein
kinase activity, which was based on a competitive catalytic reaction
and resonance energy transfer (RET) by assembling gold nanoparticles
(GNPs) on two-dimensional (2D) porphyrinic metal–organic framework
(MOF) nanosheets. In this work, an ECL catalytic reaction competing
for dissolved O2 proceeded between 2D copper-based zinc
porphyrinic MOF (Cu–TCPP(Zn)) nanosheets and luminol. Meanwhile,
the cathodic ECL of singlet oxygen (1O2), derived
from the electrocatalytic reaction of 2D Cu–TCPP(Zn), would
be reduced by the assembled GNPs due to RET, while the anodic emission
of luminol could be enhanced by GNPs with excellent electrocatalytic
activity. With the detection of protein kinase A (PKA) as an example,
this dual-mechanism-driven ECL biosensor exhibited a broad linear
range (0.005–5.0 U mL–1) and a sensitive
detection limit (0.0037 U mL–1). Compared with the
traditional single-mechanism-driven sensing strategies, the developed
dual-mechanism-driven ratiometric ECL biosensor may provide an effective
method for the design of green and ultrasensitive ECL sensors.