Isolated chloroplast membranes of the unicellular photosynthetic alga Chlamydomonas reinhardtii were exposed to low salt buffer, cryofixed, freeze-fractured, and surface replicas observed by transmission electron microscopy. Under these conditions, thylakoid membranes from wildtype cells show the particle size and distribution typical of unstacked membranes. See Fig 22 in Goodenough and Staehelin 1971 J Cell Biol 48:595-619.
Isolated thylakoid membranes were cryoprotected with glycerol, cryofixed, fractured at -100C, shadowed with Pt, and replicas prepared by carbon coating. Cleaned replicas were examined with a Philips 300 TEM. See Goodenough and Staehelin 1971 J Cell Biol 48:595-619