Proteins are characterized by their isoelectric point (pl), at which they carry no net charge. Proteins dissolved in a buffer solution with pH larger than the isoelectric point are negatively charged and positively charged when they are present in solution with a pH smaller than their isoelectric point. Consider a protein mixture consisting of protein A with pl-5.1 (MW 10,000), protein B with pl-7.1 (MW 10,000) protein C with pl-9.6 (MW 10,000) which will be separated by Capillary Zone Electrophoresis. Determine the migration order (fastest to slowest) in a buffer solution at neutral pH (negative potential applied to outlet and positive potential applied to the inlet, assume negative charge at capillary wall).

Proteins are characterized by their isoelectric point (pl), at which they carry no net charge. Proteins dissolved in a buffer solution with pH larger than the isoelectric point are negatively charged and positively charged when they are present in solution with a pH smaller than their isoelectric point. Consider a protein mixture consisting of protein A with pl-5.1 (MW 10,000), protein B with pl-7.1 (MW 10,000) protein C with pl-9.6 (MW 10,000) which will be separated by Capillary Zone Electrophoresis. Determine the migration order (fastest to slowest) in a buffer solution at neutral pH (negative potential applied to outlet and positive potential applied to the inlet, assume negative charge at capillary wall).

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter20: Molecular Spectroscopy And Photochemistry

Section: Chapter Questions

Problem 67CP

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