Specific discrimination of gram-positive bacteria and direct visualization of its infection towards mammalian cells by a DPAN-based AIEgen.

The infections caused by gram-positive bacteria (G) is a major threat to public health due to their high morbidity and mortality, and the identification of G with high sensitivity and selectivity is urgently desirable. In this paper, a probe with aggregation-induced emission (AIE) characteristic is developed and used to discriminate G from other bacteria and fungus with excellent selectivity. Thanks for its AIE feature, this probe shows intense fluorescence when interacted with G, and the signal can last for 24 h after incubating with S. aureus, which is benefit for long term tracing of translocation process with high contrast. Moreover, this probe can be used to visualize the infection processes of G towards mammalian cells, which provides valuable information for understanding the therapeutic mechanism.