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AF4/MALS/QELS/DRI characterization of regular star polymers and their "span analogs"



Leena M. Pitkanen, Andre Striegel


Asymmetric flow field-flow fractionation (AF4) coupled with multi-angle static and quasi-elastic light scattering and refractive index detectors was employed for the separation and characterization of regular star-shaped polystyrenes and their linear and span analogs in tetrahydrofuran. Stars with different arm lengths were separated from each other employing a binary slope cross-flow gradient. Cross-flow optimization enabled fast separation of polystyrenes in two- and three component blends. Macromolecular parameters were obtained using light-scattering and refractive index detection and properties of polystyrenes with different molecular architectures were compared. To our knowledge, this is the first report on the separation of star polymers with AF4. Novel characterization approaches are of importance as star-shaped molecules with different structures and functionalities have gained significant interest in many fields including medicine and nanotechnology, among others.


Asymmetric flow field-flow fractionation, separation science, star polymers, polystyrenes, light scattering


Pitkanen, L. and Striegel, A. (2014), AF4/MALS/QELS/DRI characterization of regular star polymers and their “span analogs”, Analyst, [online],, (Accessed June 24, 2024)


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Created October 14, 2014, Updated October 12, 2021