LR Gold™ was originally designed primarily for embedding unfixed tissue at low temperature. This enables enzyme histochemistry and immunocytochemistry of many fixation-sensitive and temperaturelabile enzymes and antigens to be carried out in 1 - 4µm resin sections. It is an acrylic resin with low viscosity. The resin may be cured at temperatures down to -25°C using a visible light curing source and benzil, a light sensitive initiator. It is recommended that polyvinylpyrrolidone (PVP) is used to protect unfixed tissue from osmotic changes during processing. It has also been found to have certain advantages over other resins for use with fixed tissue. It can be used in place of LR White protocols when lower temperatures are required.
The resin and activator are irritants.