I was lucky enough to get my hands on some Foldscopes for a STEM outreach activity. The goal with the Foldscopes was to view C. elegans using as simple of a setup as possible so that all of my students could try something similar at home.
For my light source, I followed the suggestions in this post:
but found that regular masking tape worked just fine instead of conductive copper tape.
I was inspired by this post (below) about the dark field setup for C. elegans using because they are transparent and hard to visualise.
I decided to give things a go for myself using the dark-field Sharpie method. Unlike some suggestions, I found that the “dotting” method didn’t work for me as well as the “line” method on a glass slide.
Here’s a picture of the back of my Foldscope. I have two watch batteries taped down simply so it sits evenly.
I then pipetted roughly 20 uL of a solution containing C. elegans in M9 buffer onto a glass slide. On either end of the glass slide, I have some cardboard to create space so the C. elegans don’t get squished, and then used another glass slide and some masking tape to sandwich everything together like so:
In the end I was able to get the following video:
— Gabi Heller (@G_T_Heller) July 28, 2017
Reading some posts, I was very impressed to see what others have done on “the dark side” with paper apetures, etc (see below) but it was still great to see what I could get away with using a good old Sharpie.