Camphorquinone, a 1,2-diketone, is a photoinitiator that finds wide use in the curing of resin composites. It functions by initiating the chain polymerization by free radical generation; typically with the aid of co-initiator amines.,(1R)-(-)-Camphorquinone may be used as an analytical standard for the determination of the analyte in dental resin composite restorations in the oral environment in contact with food and beverages, and biological samples by analytical techniques.