METHODS: This in-vitro study was conducted from April 2024 to September 2024 at Universiti Sains Malaysia and King Faisal University. Graphene oxide (GO) was reduced by dispersing GO in deionized water with sonication, followed by adding sodium hydroxide (NaOH) under vigorous stirring. The suspension obtained was centrifuged, washed, and dried to yield reduced graphene oxide (rGO). For functionalization, rGO was dispersed in ethanol and mixed with methylene blue (MB) solution, followed by stirring and drying to obtain MB-functionalized rGO. The antibacterial and antifungal activities of MB alone and in combination with rGO, with or without laser exposure, were tested using the agar well diffusion method. The paired sample t-test was used to compare the inhibition zones for different treatment groups of E. faecalis and C. albicans.

RESULTS: FTIR analysis confirmed successful functionalization by identifying specific functional groups of rGO and MB. Similarly, Raman spectroscopy indicated that GO-MB had an intermediate level of defects, and SEM analysis confirmed slight morphological changes with MB molecules attached to the rGO surface. Moreover, the antimicrobial test revealed that MB/rGO with laser performed significantly better (p=0.042) than MB/rGO without laser and MB with laser group (p=0.034) against E. faecalis.