Other than ionic gelation, various methods, such as biosynthesis, are constantly being investigated for increased efficiency and reduced energy consumption. For instance, research conducted by El-Naggar in 2022 biosynthesized chitosan nanoparticles using an aqueous extract of Eucalyptus globulus Labill fresh leaves as a bio-reductant. The maximum yield of chitosan nanoparticles in this process was 9.91 mg/mL at pH of 4.5, chitosan concentration of 1%, incubation time of 60 min and temperature of 50 °C. The crystallinity, particle size and morphology of the biosynthesized chitosan nanoparticles were characterized. The chitosan nanoparticles possess a positively charged surface of 31.1 mV. Moreover, these biosynthesised chitosan nanoparticles are thermally stable, confirming their durability and stability. These biosynthesis of the chitosan nanoparticles hints at a greener application of the chitosan in the future as this method is simple and requires low energy input.