Encapsulating a Single Nanoprobe in a Multifunctional Nanogel for High-Fidelity Imaging of Caspase Activity in Vivo

Li, Q (Li, Qang)^{[ 1,2 ]} ; Plao, XK (Plao, Xinkai)^{[ 1,2 ]} ; Wang, FC (Wang, Fengchao)^{[ 1,2 ]} ; Li, XJ (Li, Xuejing)^{[ 1,2 ]} ; Yang, J (Yang, Jie)^{[ 3,4 ]} ; Liu, Y (Liu, Yang)^{[ 3,4 ]} ; Shi, LQ (Shi, Linqi)^{[ 3,4 ]} ; Liu, DB (Liu, Dingbin)^{[ 1,2 ]}

ANALYTICAL CHEMISTRY, 2019, 91(21): 13633-13638

DOI: 10.1021/acs.analchem.9b02834

摘要

The formation of a protein corona on nanoprobes in the blood can not only reduce the delivery efficiency to their destination but also inhibit the functions of the nanoprobes. Herein, we report a multifunctional nanogel that can shield a single gold nanoparticle (AuNP) probe from interaction with the serum proteins, virtually eliminating protein corona formation on the nanoprobes. As a result, the delivery efficiency of the nanogel-encapsulated nanoprobes to tumors was dramatically enhanced. When the probes are delivered into target cells, the nanogel shells are degraded in acidic endosomes, where a proton sponge effect occurs instantaneously to release the AuNP probes into the cytoplasm to realize their bioimaging functions. We demonstrated the applicability of these probes for high-fidelity, noninvasive imaging of caspase activity in both cancer cells and in tumors. This strategy offers an exciting opportunity to design high-efficacy nanoprobes for in vivo imaging.