Abstract: New inclusion complexes which are stable in their so-lid state formed of SIN-1A and cyclodextrins or cyclodextrin derivatives and optionally also containing ions as catalyst or stabilizer. The complexes release nitric oxide at room temperature upon dissolving in water or aqueous systems. The ions are preferably carboxylic acid anions such as acetate, formiate, propionate, ascorbinate, tartarate and/or lactate and/or inorganic acid anions such as phosphate, phosphite, borate, carbonate, hydrocarbonate, sulfate, sulfite and/or cations such as alkali and/or ammonium.Pharmaceutical compositions as well as kits containing the complexes. The kits are to be used as NO-liberating standards to release NO in a predictable amount and rate on dissolving in aqueous media.