Europium and Glycopolymer-Modified Silica Nanoparticles on Black Phosphorus Nanosheets for Bacterial Targeting, Imaging, and Ablation

The bacterial imaging and ablation with high specificity are urgent issues to be addressed in the accurate diagnosis and treatment of bacterial infection in clinic. The construction of an antibacterial system which integrates multiple functions, such as bacterial targeting, imaging, and bacteria-killing capability, has been a feasible strategy. In this study, europium, with excellent fluorescence imaging performance, and poly[2-(methacrylamido) glucopyranose] (pMAG), with the ability of targeting and anchoring onto the Escherichia coli K12 (E. coli K12) strain, were adopted to construct a two-dimensional black phosphorus (BP)-based nanoplatform for the target imaging of bacteria and anti-infection treatment. First silica nanoparticles (SiO2) were prepared by the Stöber method and further modified by pMAG and Eu3+ via the free radical polymerization coupled with the ion exchange. After the P–Eu coordination formed between Eu3+ and BP, the final multifunctional nanoplatform (i.e., pMAG/pVAE@SiO2-BP) was achieved. The strong characteristic emission and fluorescence properties of Eu3+ in pMAG/pVAE@SiO2-BP were confirmed by luminescence measurement. In addition, pMAG/pVAE@SiO2-BP co-cultured with bacteria could target E. coli K12, which exhibited a distinct red fluorescence. Antibacterial experiments proved the targeted antibacterial ability of pMAG/pVAE@SiO2-BP against E. coli K12. We believe that this as-proposed multifunctional BP-based nanoplatform owns promising potential for future diagnosis and treatment of bacterial infection disease.