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Chapter 27Separation and Characterization ofBiomolecules Based on Macroscopic PropertiesContents27.1 Introduction: Mechanical Motion Interacts with Mass, Shape, Charge, andPhase to Allow Analysis of Macromolecular Structure . . . . . . . . . . . . . 74227.2 Buoyant Forces Are the Result of Displacement of the Medium by an Object . . . 74227.2.1 Motion Through a Medium Results in a Retarding ForceProportional to Speed . . . . . . . . . . . . . . . . . . . . . . . . . 74327.2.2 Frictional Coeff i cients Can Be Used in the Analysisof Macromolecular Structure . . . . . . . . . . . . . . . . . . . . . . 74427.2.3 The Centrifuge Is a Device that Produces Motion by GeneratingCircular Motion with Constant Speed . . . . . . . . . . . . . . . . . . 74527.2.4 Sedimentation Occurs When Particles Experience Motion Causedby Gravitational or Equivalent Fields . . . . . . . . . . . . . . . . . . 74827.2.5 Drag Forces on Molecules in Motion Are Proportionalto the Velocity of the Particle . . . . . . . . . . . . . . . . . . . . . 75527.2.6 Fluids Will Move and Be Transported When Placed Undera Shearing Stress Force . . . . . . . . . . . . . . . . . . . . . . . . 75627.3 Systems Study in the Biological Science Requires Methods of Separationand Identif i cation to Describe the “State of a Biological System” . . . . . . . . 76027.4 Electrophoresis Is a Practical Application of Molecular Motion in anElectrical Field Based on Charge and Modif i ed by Conformation and Size . . . . 76027.5 Chromatographic Techniques Are Based on the Differential Partitioningof Molecules Between Two Phases in Relative Motion . . . . . . . . . . . . . 76327.6 The Motion Induced by a Magnetic Interaction Is Essential forDetermination of Molecular Mass in Modern Biological Investigations . . . . . 76727.6.1 Magnetic Fields Are Vector Fields of Magnetic Force that Can BeFound Throughout Space . . . . . . . . . . . . . . . . . . . . . . . 76827.6.2 Magnets Interact with One Another Through the Magnetic Field . . . . . 77027.6.3 Current Loops in B Fields Experience Torque . . . . . . . . . . . . . 77127.6.4 The Path of Moving Point Charges in a B Field Is Altered by the Interaction 77127.6.5 The Mass Spectrometer Is Widely Used Following VariousSeparation Techniques to Characterize Biological Samples . . . . . . . . 772741 P.R. Bergethon, The Physical Basis of Biochemistry,DOI 10.1007/978-1-4419-6324-6_27, C ? Springer Science+Business Media, LLC 2010