Schlichtkrull was based at NOVO Research Institute, Copenhagen. He devised the method by which the crystals of native insulin were grown for the x-ray analysis that led to Hodgkin's elucidation of the three-dimensional structure of insulin.

See also MS. Eng. c. 5588/4-6 for photocopied correspondence between Schlichtkrull and A.S. Brill, sent to Hodgkin for information. See also MS. Eng. c. 5592/20-1, MS. Eng. c. 5592/24 and MS. Eng. c. 5593/8-9.