Phototherapeutic agents constitute a powerful armory for treating cancers and infectious diseases, [1][2][3] and nanotechnology has produced multifunctional arrays with targeted cytotoxicity and labeling capabilities. [4][5][6] Such structures must be robust, well-characterized, and able to be produced at industrial scale. [7] Herein we show a multifunctional hybrid material based on zeolite L able to target, label, and photoinactivate pathogenic and antibiotic-resistant bacteria. A highly green-luminescent dye was inserted into the channels of zeolite L nanocrystals for imaging and to label the cells. The outer surface was functionalized with a photosensitizer that forms toxic singlet oxygen upon red-light irradiation and with amino groups for targeting the living microorganisms. The resulting trifunctional nanomaterial therefore shows intense green fluorescence and efficient 1 O 2 photoproduction. As a consequence, it can target, label, and photoinactivate antibiotic-resistant Escherichia coli and Neisseria gonorrhoeae. These results open fascinating possibilities for the development of the next generation of photosensitizers for phototherapy.
Recent challenges of modern pharmacology include resistance of bacteria to multiple antibiotics and of neoplastic cells to chemotherapeutics, which on the other hand cause undesired side effects. Photodynamic therapy (PDT) is an established cancer and macular degeneration treatment [1,2] and constitutes an alternative against antibiotic-resistant bacteria. [3] In PDT, a photosensitizer generates cytotoxic 1 O 2 upon irradiation with light. The ultimate goal is to develop