Very Reliable for Routine Separation of Colloids

The separation of colloids and engineered nanoparticles requires specialized techniques because their size and structure are sensitive to numerous variables, including pH, ionic strength, and shear forces. The key analytical challenges in measuring nanoparticles and dissolved metals in the environment are separating them into the different sizes/species that govern their various levels of reactivity in a non-destructive fashion, so that the measured distribution reflects natural conditions. Although these challenges can be overcome with a range of FFF systems, routinely and repeatably separating colloidal systems into the major species can be challenging. In particular, resolving mainly organic and inorganic colloidal carriers requires high resolution in the small size range (i.e. 1-10 nm), and retaining these smaller colloids requires a small membrane pore size. The Postnova MultiFlow FFF system is able to operate at the high pressures that are required to achieve separation in the small size range, and to work with the 300 Da membrane to minimize losses through the membrane pores. The system is stable and reliable under these conditions, requiring minimal maintenance and repair. The software and communications platform enables automated sequences and straightforward coupling to other detectors (e.g. ICP-MS), so that the system can run unsupervised.