posted on 2020-03-24, 16:06authored byXue Zhang, Chunhua Ren, Fang Hu, Yang Gao, Zhongyan Wang, Huiqiang Li, Jianfeng Liu, Bin Liu, Cuihong Yang
Abnormal
levels of alkaline phosphatase (ALP) activity are associated with
various diseases, and many ALP probes have been developed to date.
However, the development of ALP-sensitive probes for living cells,
especially for the detection of bacterial ALP, remains challenging
because of the complex and dynamic context. In this study, we constructed
the first fluorescent probe (TPEPy-pY) for sensing bacterial ALP activity.
TPEPy-pY is an AIEgen-peptide conjugate with property of aggregation-induced
emission (AIE) and could turn on its fluorescence by ALP-catalyzed
in situ self-assembly of the probe. The probe shows excellent selectivity
and sensitivity for ALP activity, with a detection limit of 6.6 ×
10–3 U mL–1. TPEPy-pY performs
well in detection and in situ imaging of bacterial ALP activity against E. coli. Also, the detection does not require tedious washing
steps and takes approximately 1 h, which is advantageous over commercial
ALP kits. Therefore, the proposed strategy paved a new avenue for
bacterial ALP detection, and we envision that more self-assembling
fluorescent probes will be designed with higher sensitivity in the
near future.