This paper reports the development of a novel detection method, based on th
e coupling of a biosensor measuring device and a flow-injection system, usi
ng the enzyme formaldehyde dehydrogenase and a Os(bpy)(2)-poly(vinylpyridin
e) (POs-EA) chemically modified screen-printed electrode. The sensor can de
tect 30 ng ml(-1) of formaldehyde in aqueous solution (corresponding to sub
-ppb atmospheric concentrations of formaldehyde). The sensor is selective,
inexpensive, stable over several days, and disposable, as well as simple to
manufacture and operate. The system described here can easily be adapted t
o other substrates using their corresponding dehydrogenases. (C) 2000 Elsev
ier Science B.V. All rights reserved.