he dialdehyde benzene sulphonic acidPeter Michelsen Professor, Analytical Chemistry Associate Professor, Organic Chemistry Mobile: +46737078778 Fax: +46 451 38 52 60 E-mail: peter.michelsen@anchem.su.se www.anchem.su.se/amk Stockholm University Department of Analytical Chemistry Work Environment Chemistry Esplanadgatan 9 SE-281 38 H鋝sleholm Postal address: P.O. Box 460 SE-281 24 H鋝sleholm Sweden