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Biomedical subjects

V Muth

Publications and source records attributed to V Muth.

2 recordsLinked to original sources
PubMed1985

Separation of biological macromolecules in vertical rotors using sucrose gradients shaped by a microprocessor-controlled gradient former.

The separation of macromolecules in vertical rotors using linear or isokinetic sucrose gradients permits shorter centrifugation times and a higher sample capacity compared to swing-out rotors. In vertical rotors appropriate gradients give a resolution almost identical to that in swinging bucket rotors. This could be demonstrated for the isolation of polysomes and oligonucleosomes from rat liver. A microprocessor-controlled gradient former is presented which produces gradients of any desired shape. This device has been applied to prepare gradients with the desired linear or isokinetic shape after reorientation in the vertical tube during centrifugation.

Animals↗
PubMed1984

A magnetic viscometer for shear-sensitive macromolecules.

This paper is a report about a rotation-viscometer with a submerged rotor which has been developed for measuring the viscosity of biological macromolecules. The device avoids the effects of surface disturbance. The rotor is centered and height-balanced electromagnetically and is controlled by a light barrier. The driving force is a rotating electromagnetic field and rotor revolution periods are measured by an electronic timer controlled by a second ligh barrier. Shearing effects are negligible if very slow revolutions are pre-selected; thus, intrinsic viscosity values for DNA can be obtained by merely extrapolating the concentration dependence. In contrast to DNA, chromatin has a very low viscosity with almost no dependence on concentration. If the ionic strength of a chromatin solution is decreased, the viscosity increases due to structural unfolding.

Animals↗