▎ 摘　　要

NOVELTY - The assembly has formaldehyde dehydrogenase attached to graphene (122) by a polymeric electrolyte linking agent i.e. polydiallyldimethylammonium chloride. A working electrode (151) and a counter electrode (152) are arranged on a structural substrate (110). A dielectric protective coating (130) prevents short circuiting between the working electrode and the counter electrode while leaving an area of the graphene being exposed. A layer-by-layer (LbL) layer of immobilized enzyme is formed on the exposed area of the graphene. USE - Formaldehyde sensitive assembly for use during manufacturing of a formaldehyde electrochemical sensor used for measuring formaldehyde concentrations within a sample i.e. gaseous sample (all claimed) such as air. ADVANTAGE - The assembly provides an economical, robust and highly sensitive formaldehyde sensor providing quick response. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for the following: (1) a formaldehyde electrochemical sensor (2) a method for measuring formaldehyde concentration within a sample. DESCRIPTION OF DRAWING(S) - The drawing shows a side cross-sectional view of a formaldehyde interactive component of a formaldehyde electrochemical sensor and depicting a supply of NAD plus in fluid communication with the formaldehyde interactive component. Structural substrate (110) Formaldehyde dehydrogenase attached to graphene (122) Dielectric protective coating (130) Working electrode (151) Counter electrode (152)