Simplified Classroom Synthesis of Rose Bengal-Encapsulated Chitosan Nanoparticles for Photodynamic Therapy

Abstract

The synthesis and characterisation of nanoparticles provide an engaging and practical approach to integrating nanotechnology into educational settings. This study outlines a streamlined and cost-effective experiment for synthesizing Rose Bengal encapsulated chitosan nanoparticles, with the synthesis step completed within 60 minutes, making it suitable for classroom-based experiments. The formulation employs chitosan as a biodegradable polymer, sodium tripolyphosphate for ionic crosslinking, and acetic acid to enhance chitosan solubility in an aqueous medium. Post-synthesis purification was achieved using dialysis, ensuring improved stability and size uniformity of the nanoparticles. Characterisation through scanning electron microscopy and dynamic light scattering confirmed a particle size distribution between 100–300 nm, with an average size of around 200 nm, ideal for biomedical applications, including photodynamic therapy (PDT). This experiment supports green chemistry principles by avoiding toxic reagents and minimising waste while serving as a practical, interdisciplinary learning tool that reinforces both theoretical knowledge and hands-on skills in polymer science, nanoparticle synthesis, and biomedical applications such as PDT. As such, it offers an accessible and impactful addition to a nanotechnology-focused educational curriculum.