Enhanced visible light promoted antibacterial efficiency of conjugated microporous polymer nanoparticles via molecular doping.

The increase in the resistance of bacteria to antibiotics is one of the main concerns of public health and holds a great demand in the development of new disinfection methods. Photodynamic therapy (PDT) has been considered as a promising alternative approach towards the eradication of bacteria and great attention has been dedicated to the use of non-toxic and pure organic PDT agents. Herein we report the structural design method of a series of conjugated microporous polymer nanoparticles (CMP NPs) as a new class of highly effective photoactive materials for the inactivation of bacteria in water upon visible light exposure. Through molecular doping of electron-withdrawing moieties into electron-donating polymer backbones, enhanced antibacterial properties are demonstrated upon the inactivation of Escherichia coli K-12 and Bacillus subtilis mainly by means of photogeneration of singlet oxygen as the main photogenerated active species. Additionally, the high stability, reusability and disinfection mechanism of the CMP NPs are also described.