A Trypan Blue-Based ELISA Practice Test to Evaluate Trainee Performance

Enzyme-linked immunosorbent assay (ELISA) is a valuabletool invarious chemical and biological fields for investigating the presenceand quantity of proteins of interest in given samples. The high importanceof the assay makes it widely used in biological research and hencea crucial skill to master for up-and-coming scientists. A major impedimentto teaching the skill to new students in research laboratories isthe high cost of commercial ELISA kits. As a result of the cost ofthe kits, most investigators prefer that more experienced studentsor technicians carry out the assay to prevent errors, thus deprivingless experienced students the chance to actively learn the process.Here, we present a practice ELISA test that can be done in any laboratoryusing different dilutions of trypan blue as the reagents and samples,thereby creating a product at one-hundredth the cost of the leastexpensive ELISA kits. Research has continuously shown that activelearning tools such as this simulation enhance student engagementand self-efficacy. This practice test also generates a numerical scorebased on the students' accuracy in pipetting and attentionto detail, allowing students to identify sources of error. Therefore,the practice ELISA experiment acts as a medium to teach proper techniquebefore performing a real ELISA, thus avoiding wasting expensive reagentsand limited samples.