At-Home Real-Life Sample Preparation and Colorimetric-Based Analysis: A Practical Experience outside the Laboratory

As teaching laboratories stand empty in light of COVID-19, we extended the practical experience from the laboratory to the safety of the students’ homes. We developed a simple, robust, and versatile at-home experiment that teaches solution preparation, calibration curves, real-life sample preparation, and data analysis to second-year analytical chemistry students. Solutions were prepared using common kitchen tools and readily available corn starch, syringes, and trophic iodine for a low cost below $20. A calibration curve for the brightness of corn starch–iodine solutions as a function of starch concentration was prepared. Solutions were imaged using a smartphone camera, and the brightness of each solution was quantified using ImageJ. Starch was extracted from a ripe banana and quantified using the calibration curve. Extending the practical experience to students’ homes in the age of COVID-19 not only provides them with a better sense of the real chemistry laboratory they will one day return to but also helps solidify and expand on key concepts learned in the virtual classroom.