Exploring the Syntheses and Biomedical Applications of Nanoparticles: Simple Activities and Demonstrations for Middle and Early High School Students

Nanoparticles (NPs) can exhibit unique properties distinct from their bulk counterparts. This has led to their utilization in many fields; most notably, they have been implemented in numerous biomedical applications. Given the significance of these applications, introducing students to nanoscience early can be highly beneficial. This paper outlines an outreach activity designed as an introduction to nanoscience for middle and early high school students, focusing on two of the most widely studied NPs in biomedicine: magnetic iron oxide nanoparticles (IONPs) and gold nanoparticles (Au NPs). The 2 h teaching session consists of four parts: two synthesis demonstrations and two interactive activities, using only nonspecialized apparatus and cost-effective materials. In the first demonstration, Au NPs are synthesized through chemical reduction of an Au salt, employing lemon juice as a reducing agent. The subsequent activity employs these NPs in an exhibition of colorimetric sensing. In the second demonstration, IONPs are synthesized through coprecipitation. Finally, the students employ ferrofluids to visualize the magnetic interactions that take place when IONPs come into proximity of a magnetic field. A series of learning goals are outlined, with assessment through in-session questions and a feedback session. The activity has been successfully implemented at an outreach event, where each section was well-received. Student responses to the questions and feedback showed strong engagement and indicated a clear understanding of basic nanoscience concepts, including NP properties, synthesis, and biomedical relevance, particularly for Au NPs and IONPs.