Do I need to keep the VitroGel-Cell mixture in an ice bucket?

No. Unlike Matrigel, VitroGel is ready-to-use and can mix with a cell suspension at room temperature. If you are wondering how gelation works, understand here: How Gelation Works With VitroGel Hydrogels.

After the hydrogel and cell suspension are mixed and transferred to a syringe, you can put the mixture on ice, or 4 degrees Celsius, for 5-10 minutes to accelerate the injectable hydrogel formation and ensure a homogenous cell suspension. After that, the hydrogel can be kept at room temperature for long-term injection.

Alternately, if you don’t want to use cold temperature for any part of the protocol, simply put the hydrogel-cell mixture at room temperature for 15 minutes for gel stabilization before injection. VitroGel has a unique shear-thinning and rapid recovery property, which can maintain a long-term injectable status (hours) and excellent cell retention after injection without the needle clogging issue (Please check this page for more details and illustrated protocol).