Studies on mixed micelles of triton X–100 and phosphatidylcholine using nuclear magnetic resonance techniques

The addition of the nonionic detergent Triton X‐100 to aqueous phosphatidyl‐choline dispersions converts the bilayer structures to mixed micellar structures containing Triton X‐100. High‐resolution nuclear magnetic resonance spectroscopy at 220 MHz was used to follow this conversion, and the general spectral characteristics of the mixed micelles are presented. The results are discussed in terms of the precise change in structure which occurs as Triton is mixed with the phospholipid bilayers, and it is concluded that, above a molar ratio of about 2:1 Triton to phospholipid, most or all of the phospholipid is in mixed micelles. The relevance of these results to the study of enzymes which require substrate in the form of micelles is discussed.