Theranostic platforms for specific discrimination and selective killing of bacteria

Bacterial infections are serious threats to public health due to lack of advanced techniques to rapidly and accurately diagnose these infections in clinics. Although bacterial infections can be treated with broad-spectrum antibiotics based on empirical judgment, the emergence of antimicrobial resistance has attracted global attention due to long-term misuse and abuse of antibiotics by humans in recent decades. Therefore, it is imperative to selectively discriminate and precisely eliminate pathogenic bacteria. Herein, in addition to the conventional methods for bacterial identification, we comprehensively reviewed the recently developed theranostic platforms for specific discrimination and selective killing of bacteria according to their different interactions with the target bacteria, such as electrostatic and hydrophobic interactions, molecular recognition, microenvironment response, metabolic labeling, bacteriophage targeting, and others. These theranostic agents not only benefit from improved therapeutic efficiency but also present limited susceptibility to induce bacterial resistance. The strategies summarized in this review will open up new avenues in developing effective antimicrobial materials to accurately diagnose and treat bacterial infections in the post-antibiotic era. Statement of significance: Bacterial infections are difficult to be rapidly and accurately diagnosed, and are generally treated with broad-spectrum antibiotics, which leads to the development of drug resistance. By integrating imaging modalities and therapeutic methods in a single treatment, various theranostic agents have been developed to address the abovementioned issues. Therefore, the emerging theranostic platforms for selective identification and elimination of bacteria based on the distinct interactions of the theranostic agents with the target bacteria are summarized in this review. We believe that the information provided in this review will guide researchers in designing advanced antibacterial theranostics for practical applications in the post-antibiotic era.