Hormone Studies with the Ultracentrifuge III. An Application of Toepler's Schlieren Method to the Analytical Ultracentrifuge

Abstract

A brief outline is given of the principles and uses of the analytical ultracentrifuge in biological research. The principles of the Schlieren method of measuring sedimentation rates are described refractive index gradients in colorless liquids are employed to locate sedimentation boundaries. A detailed description is given of the optical system and knife edge assembly that has been incorporated with the authors'' air-driven vacuum ultracentrifuge. The sensitivity of detecting refractive index gradients is high; the practical sensitivity is limited by compressibility effects in the analytical cell.