Multiwavelength LUMiSizer® - The complete dispersion laboratory in one instrument determines particle and dispersion properties, filter media and membrane resistances.

The LUMiSizer® determines the hydrodynamic particle density, separation velocity distribution, and particle size distribution according to ISO 13318, in addition to the direct accelerated stability result (ISO/TR 13097:2013; ISO/TR 18811:2018) via accelerated separation. The new Generation 4 multiwavelength LUMiSizer is the first to provide a temperature ramp during separation, analogous to real-time temperature cycling tests.

The analytical multi-sample LUMiSizer centrifuge is also used to determine the filter medium or membrane resistances. In-situ changes in the particle concentration of the entire sample are tracked in time during centrifugation using STEP Technology® and are also used for volume determination. Specially developed filtration measuring cells collect the sample to be filtered, including the resulting filtrate, and allow the use of different filter media. Up to 12 measuring cells can be used. The filtration pressure is applied by the centrifugal force acting on the sample, which is easily programmed via the rotor rotation speed. The system can achieve maximum pressures of up to 7-105 Pa. Typical sample volumes are approximately 1 ml. Filter media with a thickness of several micrometers up to 6 mm and a diameter of 7 mm can be used.

The developed analytical method represents a new laboratory technique for characterizing flat filter media as well as the filterability of dispersions and solutions (e.g. suspensions, protein solutions, extracts, etc.). It requires no external pressure generation and minimal cleaning effort. Due to the small sample volumes and filter media size, it is advantageous for development projects and valuable samples.