TABLE OF CONTENTS The current trends in AUC of colloids can be divided into three sub categories. These are: (a) Improvement of data-evaluation methodologies, (b) new detection systems, and (c) application of AUC to novel systems. Whereas point (a) is mainly brought forward by the community interested in biophysical questions, new detection systems are (and have been) developed by very few groups worldwide. This could be a reflection that most AUC users are satisfied with the currently commercially available UV Vis spectrophotometer and Rayleigh interference optics of the Beckman XL-I, as these optical systems are sufficient to address the large majority of questions related to the ultracentrifugation of biopolymers. Point (c) in the above list is very relevant to the investigation of colloidal systems, as most AUC methodology has been developed for biopolymer problems and is not always directly adaptable to problems of colloid analysis. For example, for a polydisperse colloid, a simple sedimentation velocity experiment may make the application of a speed profile necessary. Therefore, colloid analysis by AUC is somehow still in its infancy with respect to methodology and data evaluation. The good thing about colloid analysis by AUC is the versatility of the technique, which is displayed in this chapter. Therefore, the potential of AUC for the analysis of colloids is by no means exhausted yet, and many future methods are expected to be developed in the future, likely catalyzed by development of new detection systems. In addition, the growing interest in nanotechnology...
