Interface fibrinogen, globulins, albumin

Reliable circular dichroism spectra cannot be obtained from crystalline, oriented polypeptide material that is birefringent or scatters light. However, monolayers of protein do not appear to provide anomalous spectra (4,15), probably because of the relative uniformity of the film and the minimal refractive index increment at the protein/water interface. Nevertheless, previous results from this and other laboratories (3,16,17) have shown that albumin and fibrinogen molecules tend to lie flat, that is, with their long axes parallel to the surface, whereas globulins lie perpendicular to the surface. 

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