CaMPARI photoconversion
CaMPARI fluorescent protein was originally developed by Howard Hughes Medical Institute’s Janelia Research Campus. This protein enables permanent marking (green to red conversion) of active nerve cells when violet light and increased levels of intracellular calcium are present. CaMPARI has been utilized in freely moving animals such as zebrafish larvae, flies, and c. elegans.
Benjamin F. Fosque et al. ,Labeling of active neural circuits in vivo with designed calcium integrators.Science347,755-760(2015).DOI:10.1126/science.1260922
Our Design
Our chamber is designed for studying c. elegans in 9cm diameter petri dish. We utilized two 100W LED UV Black Light purchased through Amazon (~$35 for 2 pack). The spectrum measurement shows the peak at 402nm with a decent intensity at 405nm for CaMPARI photoconversion.
Spectrum measurement.
For chamber construction, we utilized the mounting holes on the LED, and laser cut walls, doors, and tray for the petri dish. Holes were cut on the door and front walls to embed magnets. A 3D printed handle is also added to the door to make the door easily removable. The .dxf and .stl files for constructing the chamber is shown in the list below.
Laser cut with 6mm (0.236”) thick white acrylic:
Front walls (cut 2 pieces, middle holes tapped to 8-32, embed 1/8” diameter magnets in 4 corner holes)
Side walls (cut 2 pieces, holes tapped to 8-32, glue guiding bars to the inside face of the chamber)
Front door (cut 1 piece, embed 1/8” diameter magnets in each hole in the corners, tap 2 center holes to 1/4”-20)
Guiding bars (cut 4 pieces)
Back wall (cut 1 piece, holes tapped to 8-32)
Laser cut with clear 6mm (0.236”) thick acrylic:
Petri dish tray part 1 (cut 1 piece and glue to petri dish tray part 2)
Laser cut with clear 1mm (0.04”) thick acrylic:
Petri dish tray part 2 (cut 1 piece and glue to petri dish tray part 1)
3D printed with PLA:
Door handle (compatible with 1/4”-20 socket head screw, length 1/4”) .stl file is exported in unit [mm].
Future Improvements
It has come to our attention that the heat generated by the LEDs could raise the temperature inside the chamber. In the future, fan(s) could be added to the side walls for convective cooling.