Photoinduced antibacterial activity of NRC03 peptide-conjugated dopamine/nano-reduced graphene oxide against Staphylococcus aureus

In recent years, several drugs have become relatively easy to obtain with the rapid development of the economy and improvement in people's living standards. However, pathogenic bacteria have evolved strains that are resistant to certain drugs, such as antibiotics. Peptides are generally considered to be safe, have high tolerance to drugs, and are easy to manufacture. However, peptides are easily decomposed in complex biological environments. To solve this problem, many studies have modified peptides on the surface of nanomaterials to increase their functionality, biocompatibility, and stability. Meanwhile, nanomaterials have exhibited good absorption of near-infrared (NIR) light. When the NIR laser is focused on nanomaterials, photons are absorbed and the energy of the photons is converted into heat. Low-toxicity NRC03 peptide-conjugated dopamine/nano-reduced-graphene oxide (NRC03-DA/nRGO) nanomaterials are synthesized in this study for antibacterial testing using photothermal technology. The strains used in this study were Gram-positive Staphylococcus aureus (S. aureus). Our results indicated that the synthesized NRC03-DA/nRGO exhibits good absorption of NIR light and high photothermal conversion efficiency. Moreover, the synthesized NRC03-DA/nRGO inhibits the growth and survival of S. aureus. When the NRC03 peptide is modified on the surface of DA/nRGO, its biological stability is improved and the photothermal effect generated by NIR light produces additive effects, thereby indicating potential antibacterial applications.