Capillary array electrophoretic NMR of proteins in biological buffer solutions.
The capillary array electrophoretic NMR (CA-ENMR) was developed to study protein mixtures in biological buffer solutions of high ionic strength. By enhancing the strength of the effective electric field across the sample, the technique permits the detection of the electrophoretic motion of 1 mM lysozyme in 50 mM NaH(2)PO(4) aqueous solution, which was previously not achievable using conventional ENMR. Heat-induced convection was dramatically reduced by blocking convective current loops and by improving the efficiency of heat exchange. Thus, the capability of ENMR study of electrolyte solutions was extended from low to high ionic strength. In addition, capillary walls reduced rf-induced electrical eddy current, thereby maintaining good probe Q factors. Because of its parallel configuration to the static magnetic field, the capillary array chamber produced no susceptibility distortions of the ENMR signal. The technique offers great potential in characterizing multiple protein conformations and protein interactions in solution.
He
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Department of Chemistry, University of Connecticut, Storrs, Connecticut, 06269, USA. qiuhong@nucleus.chem.uconn.edu
Liu
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Y
Sun
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H
Li
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D002021:Buffers; D004586:Electrophoresis / Q000295:instrumentation*; D004867:Equipment Design; D009113:Muramidase / Q000737:chemistry*; D019906:Nuclear Magnetic Resonance, Biomolecular / Q000295:instrumentation*; D011506:Proteins / Q000737:chemistry*
D002021:Buffers; D011506:Proteins; D009113:Muramidase