Video resources for teaching agarose gel electrophoresis

The first time you teach your students electrophoresis, there’s a lot of preparation behind the scenes. Not only do you need to choose the experiment, you need to prepare the rest of the materials – for example, background reading about the science, history of the technique, skills practice (like pipetting), and how to “read” the results. To support you in your teaching, we have compiled this list of resources to help you through the entire experiment from the prep to the analysis.

First, the background. Each kit comes with background literature that explains the science and the theory of the experiment. For electrophoresis experiments, we have an accompanying video that describes the history of electrophoresis. (If you prefer blog posts, here is one that shares some of the main points of the video.) We also include safety data sheets (or SDSs) with every kit. Before you do the experiment with your students, you can use these forms to teach your students about lab safety.

In electrophoresis, we are loading very small volumes – a sample less than the volume of a raindrop – and we need to make sure that our measurement is the same every time.  We can use adjustable volume micropipettes make these measurements. When using an adjustable volume micropipet, we want to choose one that can measure within the correct range.  In our electrophoresis experiments, we load 35 microliters per lane, so we want to use the 20-200 microliter pipet.  If we use a pipet to measure outside its range, two things happen.  One, our measurement may not be accurate.  Two, we may break the pipet.  So, be sure to choose carefully, and practice!

After loading the gel, we run current through the system to separate the DNA samples by size. Of course, you may still have more questions! This blog post rounds up the most common questions our technical support scientists receive regarding electrophoresis. Still have questions? Contact our scientists by emailing us at or calling us at +1-800-338-6835 (Hours: M-F 8AM – 5PM ET)

Does the percentage of agarose in your gel matter? What happens if we use water instead of buffer when performing our experiment? We have videos that ask those questions and test them experimentally. Do you have a specific question that you would like our scientists to test? Let us know by filling out this form!

After the gels have run, we analyze the gels. Each experiment has a different banding pattern that gives us the information to answer the questions in the kit literature. To determine the size of each band in our experimental, we use the DNA ladder to create a standard curve. While creating a standard curve is a great integration of mathematics in the biotechnology classroom, this analysis can be tricky for students. We created two videos to walk your students through the process – one which focuses on using the ladder, and a second which focuses on creating the standard curve. (We also have a quick guide to help you integrate technology to make your measurements.) Need to store your gels after running them? We have some information on the best ways to store your gels in this blog post.

And, for you the teacher, we have resources to refresh you before you run your first electrophoresis experiment of the semester. First, we have two videos (and a blog post) to help you with your gel preparation. The first video shows how to prepare the agarose and the gel casting system. Don’t have a microwave? No problem! The second video shows how we can use a small rice cooker to melt the agarose. This is a tried-and-true method that we use when we perform in-person professional development sessions at Science Education conferences where we do not have access to a microwave or hot plate. We also have videos to help you properly dilute your electrophoresis buffer and how to use Flash Blue to stain your gels.

After performing the experiments, let us know how they went! We love to see your results on Instagram, Facebook, or Twitter. Don’t forget to tag us! We’ll send you an exclusive Edvotek gift.

Are we missing a resource that you’d like for your students? Or do you have a scientific question that you’d like answered? Don’t hesitate to contact us at or let us know in this form: