Had it not been for chemistry in science we may have still may deprived of many products around us used in everyday life. Research in the field of chemistry has made us aware of electrons, radio activity, atomic theory and so on. Most of the significant invention in chemistry, which are resultants of a chemical reactions are finally some kind of chemical substance. Securing these data is of high importance. Several techniques are used for this purpose DNA steganography is promising due to its high storage capacity. In this paper we propose encryption of chemical compounds using DNA steganography with graph domination as a tool for encryption.