The RadiCoat 2-hydroxyethylbenzene functionalised coating is a multilayer film on glassy carbon consisting of 2-hydroxyethylbenzene groups, electrochemically immobilized through reduction of 4-(2-hydroxyethyl)benzenediazonium tetrafluoroborate. The multiple surface hydroxyl groups makes the surface hydrophilic. In addition, these nucleophilic groups may serve reactive moieties to chemically immobilize e.g. biological markers or chemical functional groups. As an example, RadiCoat 2-hydroxyethylbenzene functionalised coating can readily be used for immobilization of initiators for atom transfer radical polymerization (ATRP), and thereby as a platform to create so called polymer brushes (Langmuir 2011, 27, 1070–1078; ACS Appl. Mater. Interfaces 2014, 6, 21308−21315). RadiCoat 2-hydroxyethylbenzene functionalised surface films are 5-7 nm thick and highly uniform.