DPX Mountant

A mixture of distyrene (a polystyrene), a plasticizer (tricresyl phosphate), and xylene, called DPX, was introduced in 1939 and later modified by the substitution of a more satisfactory plasticizer, dibutylphthalate (butyl, phthalate, styrene - BPS). This colorless, synthetic resin mounting media is now available at Electron Microscopy Sciences, DPX, and it has generally replaced xylene-balsam. They preserve stains and dry quickly; surplus mountant may be peeled off the preparation after cutting around the coverslip with a razor blade or scalpel. They are not recommended for use with thick sections (eg. cellulose nitrate) where there is a danger of retraction of the mountant upon drying.