Hybridization solution (12 slides)

Recipe

Reagent	Quantity (for 12 slides)	Final concentration
In situ salt solution (10X)	240 μL	12.5%
Formamide (100%) (RNase-free)	960 μL	50%
Dextran sulfate (MW 500) (50% in H₂O)	480 μL	25%
Denhardt’s reagent (50X)	48 μL	2.5%
tRNA (Sigma) (10 mg/mL in H₂O)	216 μL	11.25%

Prepare all reagent stock solutions in RNase-free H₂O and store at −20°C. Incubate dextran sulfate solution at 85°C to reduce viscosity before pipetting. Mix all other reagents in a 2-mL RNase-free microcentrifuge tube and incubate at 85°C until needed; do not allow solution to cool down or it may solidify. Prepare fresh before use.
The calculations provided are for a total of 12 slides; calculations can be easily adjusted for a different number of slides.