Customized Lanthanide Nanobiohybrids for Noninvasive Precise Phototheranostics of Pulmonary Biofilm Infection.

A noninvasive strategy for diagnosis and precise treatment of bacterial biofilm infections is highly anticipated but still a great challenge. Currently, no biofilm-targeted theranostic agent is available. Herein, we fabricated intelligent theranostic alginate lyase (Aly)-NaNdF nanohybrids with a 220 nm sunflower-like structure (NaNdF@DMS-Aly) through an enrichment-encapsulating strategy, which exhibited excellent photothermal conversion efficiency and the second near-infrared (NIR-II) luminescence. Benefiting from the site-specific targeting and biofilm-responsive Aly release from NaNdF@DMS-Aly, we not only enabled noninvasive diagnosis but also realized Aly-photothermal synergistic therapy and real-time evaluation of therapeutic effect in mice models with biofilm-induced pulmonary infection. Furthermore, such nanobiohybrids with a sheddable siliceous shell are capable of delaying the NaNdF dissolution and biodegradation upon accomplishing the therapy, which is highly beneficial for the biosafety of theranostic agents.