RAPID METAL-INTERACTION CHROMATOGRAPHY OF PROTEINS AND PEPTIDES ON MICROPELLICULAR SORBENTS

Short columns packed with micropellicular stationary phases consisting of 2-mu-m fused silica microspheres with covalently bound iminodiacetate (IDA) functions at the surface were used for rapid HPLC analysis of proteins by metal-interaction chromatography (MIC). In contrast to conventional porous stationary phases which elicit relatively long analysis times, the columns packed with sorbents having micropellicular configuration and Ni2+ or Co2+ chelated by the IDA functions yielded separation of model proteins in a few minutes with good resolution. A Fe3+/IDA column was used for separation of phosphorylated and non-phosphorylated peptides derived from enzymatically digested erythrocyte membrane proteins. Stability of the Fe3+/IDA column was quite satisfactory as determined by monitoring the iron content of the column effluent and by measuring the amount of iron present in the stationary phase.