FIGURE 3.

Chemical synthesis and purification of des-Phe^B1-DKP-insulin. A, reverse-phase HPLC chromatogram documenting 3-fold reduced yield of des-Phe^B1 analog following chain combination due to side products, including non-native disulfide isomer (arrow at 51.6 min). B, final purification yielded a single symmetrical peak of appropriate molecular mass and native receptor-binding affinity. Mono-component reverse phase-HPLC profile was obtained under gradient elution conditions employing either acetonitrile or methanol as co-solvents.