I was curious to see if the Lipid Shell Micro-Bubbles we’ve been using in our lab as a contrast agent for Optical Coherence Tomography will be visible with the Foldscope.
The Micro-Bubbles I examined had a C3F8 gas core, wrapped in a lipid shell, and their diameter ranged from 0.6 micron to 1.2 micron. Approximately 5 microliter sample with an unknown concentration of micro-bubbles was loaded on a glass slide.
The image below shows the full field of view, as seen with the Foldscope. the micro-bubbles are indeed visible, mainly at the center of the image which is in focus.
The image below shows the micro-bubbles with maximum zoom (iPhone XR). As can be seen, most of the micro-bubbles are clamped together, since their concentration is high and they have been stored in a vial for the past few months.
Overall, Foldscope is a powerful optical microscope that enables microscopic work anywhere, for only $2. Within a few minutes of easy and fun setup, I was already imaging!