The surface functionalization of nanomaterial is relevant in terms of its selectivity toward a bacterial strain. Recently, semiconducting nanomaterials have been gaining much attention in the development of nanomaterial-based alternative antibiotics. Among the various semiconducting materials, molybdenum disulfide (MoS2) has been gaining considerable interest due to its unique electronic, physical, and chemical properties. The semiconducting nature, high colloidal stability, and biocompatibility make it a promising candidate in the field of biomedical research. The development of antibacterial material based on MoS2 quantum dots is still in its infancy. Here, we have explored the effect of hydrophobic amino acid-modified MoS2 quantum dots toward their antibacterial activity. Functionalization enhances the antibacterial activity and selectivity depending on the amino acid residue. MoS2 quantum dots with a leucine-functionalized ligand show selective antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), whereas MoS2 quantum dots with a phenylalanine-functionalized ligand show almost equal antibacterial efficacy against both MRSA and Pseudomonas aeruginosa (PA).

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Enzyme inhibitors play a crucial role in diagnosis of a wide spectrum of diseases related to bacterial infections. We report here the effect of a water‐soluble self‐assembled PdII8 molecular cage towards β‐galactosidase enzyme activity. The molecular cage is composed of a tetrapyridyl donor (L) and cis‐[(en)Pd(NO3)2] (en=ethane‐1,2‐diamine) acceptor and it has a hydrophobic internal cavity. We have observed that the acceptor moiety mainly possesses the ability to inactivate the β‐galactosidase enzyme activity. Kinetic investigation revealed the mixed mode of inhibition. This inhibition strategy was extended to control the growth of methicillin‐resistant Staphylococcus aureus. The internalization of the Pd(II) cage inside the bacteria was confirmed when bacterial solutions were incubated with curcumin loaded cage. The intrinsic green fluorescence of curcumin made the bacteria glow when put under an optical microscope. Furthermore, this curcumin loaded molecular cage shows an enhanced antibacterial activity. Thus, PdII8 molecular cage is quite attractive due to its dual role as enzyme inhibitor and drug carrier.