Harnessing Quintuple Layer Dependent Antisuperbug Properties from 2D Bi₂Se₃ Topological Quantum Material for Targeted...

Staphylococcus aureus (MRSA) biofilms significantly hinder the effectiveness of conventional antimicrobial agents, which pose a major challenge in treating biofilm infections in clinics. In the current paper, we unveiled targeted superbug biofilm eradication using Bi₂Se₃ nanoplate based quantum material, where antisuperbug properties are strongly influenced by its unique layered structure composed of quintuple layers (QLs). We show that control over targeted eradication of MRSA superbugs can be achieved by harnessing QL dependent anti-MRSA properties for the Bi₂Se₃ nanoplate. Reported data demonstrated that the quantum material has the capability for 100% selective eradication of MRSA by selectively targeting the lipoteichoic acid (LTA) of Gram-positive bacteria. However, due to the lack of binding with lipopolysaccharide of Gram-negative superbugs, the quantum material lacks effective eradication of carbapenem-resistant E. coli and Salmonella DT104 superbugs. Experimental data show that the 3QL thick Bi₂Se₃ nanoplate has the capability for wrapping MRSA bacteria very strongly via binding with LTA, which can physically enclose the MRSA and allow superbugs to effectively isolate them from their environment, ultimately inhibiting bacterial proliferation. In addition, the minimum inhibitory concentration (MIC) value changes by an order of magnitude (∼10 to ∼100 μg mL^-1) as the thickness of the nanoplate varies from 3 to 15 QLs. Moreover, the nanoplate has the capability for the selective inhibition of MRSA biofilm growth, where the minimum biofilm eradication concentration (MBEC) varies by more than an order of magnitude with the variation of QLs. These findings demonstrate the potential of quantum materials to address the growing threat of MRSA infections.