The prospect of using guava leaf extract for biosynthesizing chitosan nanoparticles

Liela M Ali, Helmy E Hassan, Ahmed E El-Raie, Abd El-Rahman A Ahmed and Sherif S Saleh

Abstract

Chitosan is polysaccharide polymer used for biomedical applications and food packaging. The aim of this investigation is to produce chitosan nanoparticles (ChNPs) using guava leaf (Psidium guajava L.) extract as green synthesis of nanoparticles using plant leaf extract is ecofriendly and cost-effective approach. The leaves of guava are nontoxic, full of bioactive compounds, and suitable alternative to avoid chemicals used in other methods. Variations in extract preparation method and ratio of chitosan to leaf extract were examined to investigate the effect of these factors on the particles size. The characterisation of chitosan nanoparticles was conducted using dynamic light scattering (DLS), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FTIR), and zeta potential analysis. The results showed semi-spherical nanoparticles were formed at pH = 5 with an average particle size of 21.92 nm and narrow size distribution as, polydispersity index (PDI) value was 0.471. Zeta potential was −27.1 which gives reasonable stability to the nanoparticles in suspension. The effect of storage time of chitosan nanoparticles on the antibacterial activity against Staphylococcus aureus, Escherichia coli, and Bacillus subtilis was also investigated.