Below we provide the list of parts from Thorlabs, Cairns Research and other suppliers that we used to build our fluorescent mini microscopes. These microscopes will be used to perform calcium imaging in undergraduate practicals and small lab projects for level 3 students. Slightly improved, they can be used for research projects. For this we recommend using more advanced camera (e.g. Retiga R3). Due to their size, they can be used in a CO2 incubators for chronic imaging of cultured cells. See our recent paper how chronic calcium imaging be performed using conventional microscopes: https://www.future-science.com/doi/pdf/10.2144/btn-2018-0024
The microscopes were designed and implemented by Ash Cadby: https://www.sheffield.ac.uk/physics/people/academic/ashley-cadby @imagine2022 @Cadby_lab and Anton Nikolaev: https://www.sheffield.ac.uk/hearing/sensory-integration @CalcNeuro
Cheap LEDs were designed by Federico Ceriani (Marcotti’s lab).
Overall price of the microscope is £1600-1700 but can be reduced to ~1200 if you design the LEDs yourself and use filter cubes from old microscopes (we found plenty) and old objectives.
Objective part
Option 1.
CCM1-G01 30mm Cage mounted aluminium Mirror
S1TM06 SM1 to 6 mm Lens Cell adapter
C392TME-A lens (f = 2.75 mm. NA = 0.64
ER2-P4 extension rods to connect the objective to the filter cube
Option 2.
CCM1-G01 30mm Cage mounted aluminium Mirror
Objective canibalised from your old microscope (NON INFINITY CORRECTED!)
Appropriate SM1 adapter (e.g. RMS to SM1) – will depend on the objective lens
ER2-P4 extension rods to connect the objective to the filter cube
Option 1 will require a bit of fiddling with the position of the camera lens. Option 1 will also require appropriate focusing system. With option 2 we simply screw the objective lens up and down (NB! This affects the size of the sample a little).
Filter cube part
Option 1 (expensive)
Thorlabs C6W 4-way mounting cube
Thorlabs B3C/M – Rotatable cover plate
Thorlabs MF469-35 GFP excitation filter
Thorlabs MF525-39 GFP emission filter
Thorlabs MD498 Di filter R band = 452-490
Thorlabs FFM1 cage dichroic filter mount
Two Thorlabs SM1L05 short tubes to connect the excitation and emission filters to the C6W cube
Option2 (cheap)
Thorlabs C6W 4-way mounting cube
Thorlabs B3C/M – Rotatable cover plate
Filter cube cannibalised from an old microscope and glued to B3C/M using glue gun
The rest of the microscope
Thorlabs SM1L05 lens tube
Thorlabs AC254-100-A camera lens
Thorlabs SML35 3.50’’ lens tube
Thorlabs SM1A9 adapter with external C-mount thread and external SM1 thread
Thorlabs SM1T2 coupler
Camera
DCV/BFS-U3-16S2M-CS Blackfly camera NB! This camera heats a lot and requires a heatsink or to be switched of between frame acquisitions (ideally both). Otherwise its really good — lightwave, cheap (350-370 pounds) and pretty good quality.
LED
Option 1 (Thorlabs)
Thorlabs mount LED (e.g. M490L4)
Thorlabs T-cube LED driver (LEDD1B)
Thorlabs SM1L35 tube
Thorlabs SM1T2 coupler
Thorlabs ACL2520U lens (F=20mm)
You will need to spend some time to properly position the lens
Option 2 (Cairns)
Both these options do great job but are quite expensive (around £500). Here is option 3 for electronics lovers:
Option 3
Arduino uno/mega http://uk.rs-online.com/web/p/processor-microcontroller-development-kits/7154081/ (2 for monitor+controller configuration)
AD5171 digital potentiometer http://uk.rs-online.com/web/p/digital-potentiometers/8099301/
Surface Mount (SMT) Board SOT Epoxy Glass Double-Sided 23.5 x 13.5 x 1.5mm FR4 https://uk.rs-online.com/web/p/surface-mount-smt-to-through-hole-adapter-boards/7288838/?searchTerm=re906&relevancy-data=636F3D3126696E3D4931384E53656172636847656E65726963266C753D656E266D6D3D6D61746368616C6C7061727469616C26706D3D5E2E2A2426706F3D31333326736E3D592673743D43415443485F414C4C5F44454641554C542673633D592677633D4E4F4E45267573743D7265393036267374613D726539303626&dym=re90
RCD24 LED driver http://uk.rs-online.com/web/p/led-drivers/6689882/
2X 4.7 KOhm resistors
Power supply
LED (1-3 W) blue LED. E.g – https://futureeden.co.uk/products/3w-royal-blue-led-epiled-440-450nm-with-star-pcb-heatsink
If you don’t need to regulate the brightness of the LED you do not need the potentiometer. We are still working on the best way to mount these LEDs but the idea is to glue it to a Thorlab cap (SM1CP2M) and screw this onto CP02. You will also need a lens to focus the LED.
NeuroCalc 