Stapled Peptide Solution a-Helix Conversion Measurement

Stapled Peptide Solution a-Helix Conversion Measurement 

As mentioned earlier, short peptides tend to form random coils rather than an a-helix structure and not all the stapled peptides stabilize the a-helices. Circular dichroism (CD) spectroscopy is commonly used to measure the a-helix conversion enhancement of the stapled peptides. The helical content is direcdy proportional to ellipticity ([0]) or the rotation at a wavelength of 222 nm [61] therefore, the percentage of helicities can be calculated from molar ellipticities at 222 nm ([flJzzz) using —31500 (l-2.57/ ) and 0 deg cm /dmol as the values for 100 and 0% heUcity, respectively, where is the number of amino acid residues in the peptide [61]. 

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