Basic NeuroscienceDesign and construction of a modular low-cost epifluorescence upright microscope for neuron visualized recording and fluorescence detection

- We provide instructions for building a low-cost epifluorescence upright microscope.
- The design of a microscope using catalog-available parts reduces the time and price of assembling.
- This microscope is suitable for visualized recording and fluorescence detection.
- This open-box microscope allows researcher to modify it for a wide variety of experimental setups.

BackgroundOne of the limitations when establishing an electrophysiology setup, particularly in low resource settings, is the high cost of microscopes. The average cost for a microscope equipped with the optics for infrared (IR) contrast or microfluorometry is $40,000. We hypothesized that optical elements and features included in commercial microscopes are not necessary to IR video-visualize neurons or for microfluorometry.New methodWe present instructions for building a low-cost epifluorescence upright microscope suitable for visualized patch-clamp recording and fluorescence detection using mostly catalog-available parts.ResultsThis microscope supports applications such as visualized whole-cell recording using IR oblique illumination (IR-OI), or more complex applications such as microfluorometry using a photodiode. In both IR-OI and fluorescence, actual resolution measured with 2-μm latex beads is close to theoretical resolution. The lack of movable parts to switch configurations ensures stability when doing intracellular recording.Comparison with existing methodsThe low cost is a significant advantage of this microscope compared to existent custom-built microscopes. The cost of the simplest configuration with IR-OI is ∼$2000, whereas the cost of the configuration with epifluorescence is ∼$5000. Since this design does not use pieces discarded from commercial microscopes, it is completely reproducible.ConclusionsWe suggest that this microscope is a viable alternative for doing in vitro electrophysiology and microfluorometry in low-resource settings. Characteristics such as an open box design, easy assembly, and low-cost make this microscope a useful instrument for science education and teaching for topics such as optics, biology, neuroscience, and for scientific “hands-on” workshops.