Embedding Solution
Prepare a stock solution of 45% (w/v) cold water fish gelatin (CWFG; Sigma-Aldrich G7041) in water. Incubate overnight at 37°C. Store in 50-mL Falcon tubes for up to several months at 4°C.
Prepare the embedding solution by making a solution of 15% CWFG with 15% sucrose in water. Dissolve at 37°C until completely homogeneous with no air bubbles. For short-term storage, keep at 4°C for without sodium azide; this solution will be stable for at least 3–4 mo. For longer storage, add 10% sodium azide to a 0.02% final concentration.
