Analytical ultracentrifugation remains pre-eminent among the methods used to study the interactions of macromolecules under physiological conditions. Recent developments in analytical procedures allow the high resolving power of sedimentation velocity methods to be coupled to sedimentation equilibrium approaches and applied to both static and dynamic associations. Improvements in global modelin...

Glutaminase-asparaginase from Pseudomonas 7A appears to have four subunits with a molecular weight of 36,000 +/- 500 by sedimentation equilibrium in 5.9 M guanidine HCl and 34,000 by amino acid analysis. Analytic sedimentation equilibrium of the native enzyme showed a molecular weight of 140,000 +/- 3,300 with no signs of association or dissociation. Moving boundary and zone sedimentation in bu...

In this study, five different products of each metronidazole tablets and benzoate salt oral suspensions were purchased from the different retail outlets in the local market of Addis Ababa and analyzed using official methods (Pharmacopoeial methods of USP/BP/IP) by employing HPLC for the tablet dosage forms and nonaqueous titration with potentiometric end point for the suspensions. The assay res...

Vaccinia virus DNA, extracted from purified virus or from the cytoplasmic fraction of virus-infected cells very shortly after infection, was analyzed by sedimentation in alkaline and neutral sucrose gradients. The sedimentation properties of vaccinia DNA under denaturing conditions changed, immediately after penetration into the cell, from the characteristic circular viral DNA (crosslinked doub...