Facile multifunctional-mode of fabricated biocompatible human serum albumin/reduced graphene oxide/Cladophora glomerata nanoparticles for bacteriostatic phototherapy, bacterial tracking and antioxidant potential

To overcome multi-drug resistance in microbes, highly efficient antimicrobial substances are required that have a controllable antibacterial effect and are biocompatible. In the present study, an efficient phototherapeutic antibacterial agent, human serum albumin (HSA)/reduced graphene oxide (rGO)/Cladophora glomerata bionanocomposite was synthesized by the incorporation of rGO nanoparticles with HSA, forming protein-rGO, and decorated with a natural freshwater seaweed Cladophora glomerata. The prepared HSA/rGO/Cladophora glomerata bionanocomposite was characterized by spectroscopic (UV-vis, FTIR, XRD and Raman) and microscopic (TEM and SEM) techniques. The as-synthesized bionanocomposite showed that sunlight/NIR irradiation stimulated ROS-generating dual-phototherapic effects against antibiotic-resistant bacteria. The bionanocomposite exerted strong antibacterial effects (above 96 %) against amoxicillin-resistant P. aeruginosa and S. aureus, in contrast to single-model-phototherapy. The bionanocomposite not only generated abundant ROS for killing bacteria, but also expressed a fluorescence image for bacterial tracking under sunlight/NIR irradiation. Additionally, the bionanocomposite displayed pronounced antioxidant activity.