Investigating and Characterizing Chitosan Nanoparticles for Application through Electrospraying

ABSTRACT This study focuses on a detailed investigation of producing chitosan nanoparticles using electrohydrodynamic atomization (electrospraying) and explores methods to control the dimension, morphology, and distribution of the particles. This study explored how the characteristics of the solution, processing conditions, and environmental factors influence the shape and size of the chitosan nanoparticles. We used the resulting optimized parameters for the electrospraying of chitosan nanoparticles on surfaces and subsequently assessed the antibacterial efficacy of the coatings. Scanning electron microscope images and nano size measurements were taken to examine electrosprayed nanoparticles. Also, characterization of these solutions was studied. This study reveals that maintaining ideal humidity and temperature is key to controlling the physical characteristics of the particles. At the lowest humidity levels, nanoparticle merging and fibril formation were prevalent, whereas the highest humidity levels resulted in irregular cluster formations. Notably, nanoparticles formed at 40, 50, and 60 % humidity exhibited spherical shapes with reduced polydispersity, and particles at 50 % humidity showed the smallest size and least polydispersity. Additionally, an increase in temperature correlated with leading to fiber formation with smaller diameters and transition from monodisperse to polydisperse distribution. Morphological analysis revealed that the nanoparticles produced were spherical with smooth surfaces and were smaller in size, which was achieved by lowering the concentration of the polymer solution and using slower flow rates for electrospraying. Integrating and optimizing environmental, solution, and process parameters offers key insights into achieving desired characteristics for electrosprayed chitosan nanoparticles. Moreover, the outcomes demonstrated that this method could effectively eliminate up to 99.99 % of Escherichia coli and Staphylococcus aureus bacteria.