Injection Dishes for X. tropicalis Embryos

MATERIALS

Ethanol (95%)

Methylene chloride or chloroform

Cork (silicone rubber, with a diameter close to that of the Petri dish)

Petri dishes (plastic, 35-mm; Falcon 351008)

Polypropylene mesh (Repligen 146418)

Injection dishes for microinjection of Xenopus oocytes are modified Petri dishes to which a nylon mesh has been fixed to hold oocytes or embryos in place. The mesh also helps to keep track of which specimens have been injected because it holds the specimens in regular rows. Ensure that the grid fits snugly to the edge of the dish and lies flat on the surface, so that the specimens do not become trapped underneath.

1. Cut the 500-µm polypropylene mesh into circles so that it fits snugly into the Petri dishes.
2. Working in a fume hood, fix the mesh in place by melting the bottom of the plastic Petri dish with five drops of methylene chloride or chloroform. Use the silicone rubber cork to hold the grid flat while the plastic sets (∼10 sec). Double-check to be sure that the mesh is completely adhered to the dish.
3. Allow the dishes to sit overnight in a fume hood to ensure complete evaporation.
4. After complete evaporation of the solvent, rinse the dishes thoroughly with 95% ethanol and then with water before use.