[1] Her father Joe ran his own company repairing mechanical office equipment and her mother Edith Snr had worked as a seamstress before joining her husband in helping to run his business.
She eventually attended a short course at the University of Edinburgh in biochemistry, which motivated her to apply for an undergraduate degree.
She identified the structure of arylamine N-acetyltransferase and defined the mechanism of action using a catalytic triad.
In 2010, Sim moved to Kingston University as dean of science, Engineering and Computing.
[2] In 2012, Sim was awarded the British Pharmacological Society John Vane Medal.