Nicholas was born 1949 and educated at Mill Hill School. After a King's College London BSc in Physics (1972) he did his PhD (1975) in King's with Maurice Wilkins on the structural studies of cell membranes, particularly in the nervous system. In 1977 he became a Lecturer, followed by promotions to Reader (1989) and Professor of Biophysics and Anaesthetics (1993) at Imperial where his lab showed that anaesthetics work by binding specific receptors in neural cell membranes, contradicting the dominant hypothesis of the time that they influenced lipid membrane fluidity.