Polymer Separation members

Prof. Dr. Albena Lederer

Albena graduated from Sofia University St Kliment Ohridski, Bulgaria with a diploma degree in Organic Chemistry. She received her PhD in Physical Chemistry from Max-Planck-Institute of Polymer Research Mainz and University Mainz, and her habilitation degree in Physical Chemistry from Technische Universität Dresden. Currently, Albena is the head of the Center Macromolecular Structure Analysis at the Leibniz-Institut für Polymerforschung Dresden (IPF), Germany. She also holds the SASOL Chair in Analytical Polymer Science at the Stellenbosch University (SU), South Africa. Albena established the Polymer Separation Group in 2007. Today she is the Head of the Joint IPF-SU Polymer Separation Research Group.


Created by potrace 1.16, written by Peter Selinger 2001-2019

Meet our Group Members

Dr. Susanne Boye

Susanne graduated in biochemical engineering in Dresden in 2006. Afterwards, she wrote her doctoral thesis in the polymer separation field, entitled “Modern fractionation techniques for branched polymers”, at the Technical University Dresden and IPF. Since then, Susanne has been a member of the Polymer Separation Group, and established the AF4 technique at the IPF. She has further dealt with the application and further development of AF4 with multidetection systems. Susanne is particularly interested in the physicochemical and in-depth characterization of polymer-protein conjugates, complex synthetic and natural (bio-)nanostructures, and molecular interactions. She has specific expertise in the field of conformation analysis of biomacromolecules.


Joshua Johani 

Joshua is a doctoral researcher whose interest lies in natural and bio-inspired polymers. He focuses on the development of advanced multidimensional and multidetector column- or channel-based fractionation techniques for the separation and characterisation of the natural bio-resources. Knowledge of the molar mass distribution, chemical composition distribution, topology, microstructure, and structure-property relationships of the biopolymers is paramount to their unique role in the future of pharmaceutical, healthcare, cosmetic and functional food applications.


Robert Kwinda

Robert is a MSc student in Polymer Science at Stellenbosch University. His research focuses on characterisation of the structural properties of industrial polyolefins and the influence of the molecular structure on the material properties. Analytical tools employed include high temperature liquid chromatography (HT-HPLC, HT-SEC), HT two-dimensional liquid chromatography (2D-LC), and fractionation methods, including Temperature rising Elution (TREF), Crystallization Analysis Fractionation (CRYSTAF) and Molar Mass Fractionation (MMF).

Chelsea Williams

Chelsea’s research is focused on the development of advanced column- and channel-based analytical methods for the comprehensive analysis of lignin raw materials. Lignin is a heterogenous biopolymer typically considered a “waste” product from the agroforestry industry. To valorize lignin, the chemical and physical properties need to be known.


Sara Scheffler

Sara Scheffler

Sara Scheffler is the depratment secretary at the Centre for Macromolecular Structural Analysis (MSA) and is responsible for organizing Prof. Albena Lederer’s secretariat as well as supporting the staff of the working groups at MSA in all administrative areas.

Dr. Upenyu Muza

Upenyu is an expert in Field-Flow Fractionation (FFF), and his forte is the engineering and multidimensional analysis of complex nanostructures with applications in therapeutics, diagnostics and targeted medicine delivery. Currently, he is working on specialized topics relating to exosomes-polymer hybrids; Ionic polymers’; polymersome-protein hybrids; and metal-polymer hybrid nanoparticles. Upenyu is a Marie Skłodowska-Curie Actions Fellow.


Dr. Zanelle Viktor

Zanelle graduated from Stellenbosch University with a PhD in Polymer Science. Her research interest is the development of advanced multidimensional analytical techniques for comprehensive characterization of synthetic and natural polymers. She has experience with method development on both column- and channel- based separation techniques. Zanelle joined the Polymer Separation group during 2021 as a postdoctoral researcher based at the IPF, working on the M-era.net project 3D4D2.


Petronella Zabesuthu Ndlovu

Petronella graduated her MSc Polymer Science degree cum laude in 2021 from the University of Stellenbosch. In her work she addressed scientific problems relevant to our industrial partners. Petronella has gained valuable experience in the operation of high-temperature instruments and preparative fractionation methods such as temperature rising elution fractionation (TREF) and molar mass fractionation (MMF). Since 2022, she is a PhD candidate at the University of Stellenbosch.


Dr. Helen Pfukwa

Helen’s research focuses on the conversion of lignin to high value chemicals, depolymerization product characterization, and the design and synthesis of sustainable polymer materials. Her other research interests are polymer characterization focusing on the method development for synthetic, natural and bio-inspired polymers. Helen is an expert in diverse liquid and gas chromatography techniques with special emphasis on interaction chromatography and MS methods, including MALDI-TOF MS.


Petra Treppe

Petra is a vastly experienced chemical laboratory technician and chemical-technical assistant. Since 1983, she has been working at the IPF as a scientific-technical employee in the analytics department. Petra’s field of activity includes SEC, HT-SEC and AF4 measurements. She has also gathered extensive experience in the use of multidetector systems.

Eileen Schierz

Eileen is a chemical laboratory technician and have been working in analytics since 2009. Her area of responsibility extends to GC-MS and elementary analysis. Eileen also has practical experience in layer preparation, FTIR spectroscopy, ellipsometry and thermal analysis.

Alissa Seifert

Alissa finished her training as a chemical laboratory technician in 2021 at the IPF, and started working in the IPF-SU Polymer Separation Research Group in June 2021. Her area of expertise focusses specifically on size exclusion chromatography (SEC) and AF4.

Zahn Stanvliet

Zahn is a polymer science researcher who completed a master’s degree at Stellenbosch University. Her research focuses on smart nanoparticles, and in particular on utilizing Field-Flow Fractionation (FFF) to separate and characterize dual-responsive polymersomes. In her research, Zahn also investigates and characterizes the dispersity and efficacy of the responsive behavior of these polymers and their self-assembled nanoparticles through establishing an analytical approach that employs multidetector FFF.


Mawande Sigwinta

Mawande’s is a PhD candidate whose research focuses on development of advanced multidimensional methods for analysis of complex polyolefins, more specifically but not limited to, highly branched amorphous polyethylene. Analytical tools employed include preparative fractionation, column-based separation methods, such as high temperature size exclusion chromatography (HT-SEC), HT-two-dimensional liquid chromatography (2D-LC), and spectroscopic techniques, including Fourier Transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy.


Martin Geisler

Martin is a postdoctral researcher. His work looks to identify practical aspects of working with hyperbranched polyethylenes and polyesters, including their dissolution and solubility in various solvents. He conducts experiments to compare controlled changes in synthesis conditions and studies their effect on polymer morphology using Thermal Field-Flow Fractionation (ThFFF) .


Althea Carstens

Althea Carstens is a Ph.D. candidate. She joined the group in 2023 after completing her MSc in Polymer Science at Stellenbosch University. Her research focuses on the development of bio-derivable copolymers and the subsequent investigation into their self-assembly behaviour using advanced analytical techniques, including multi-detector ThFFF. She aims to contribute to the advancement and understanding of functional materials from renewable feedstocks.


Thandekile Siwela

Thandekile is a MSc student in Polymer Science at Stellenbosch University. She completed her BSc Honours in Applied Chemistry at National University of Science and Technology (NUST), Zimbabwe. Her research focuses on characterisation of the structural properties of recycled polyolefins and the influence of the molecular structure on the material properties. Analytical tools employed include high temperature liquid chromatography (HT-HPLC, HT-SEC), HT two-dimensional liquid chromatography (2D-LC), and fractionation methods, including Temperature rising Elution (TREF), Crystallization Analysis Fractionation (CRYSTAF) and Molar Mass Fractionation (MMF).

Mareike Schumacher

Mareike completed a Master degree at the Technische Universität with specialization in Analytical Chemistry. She is now working on her PhD Thesis as a joint group member with the Microplastic group at the IPF in Dresden. Within the Leibniz Excellence Project “AirPlast”, her goal will be to analyze microplastics in air samples taken at different locations. Together with the project partners in Leipzig Germany, new methods are elaborated to focus on the determination of microplastics in PM10. At the lab in Dresden, she is responsible for the confocal Raman microscopy and the pyrolysis-GC/MS techniques within this project.

Andy Scheidegger

Andy is a MSc student in Polymer Science, completing his thesis work at Stellenbosch University in collaboration with the University of Amsterdam.

group Alumni

Dr. Ndumiso Sibanda

Ndumiso’s work focused on the development of advanced analytical methods for complex polymer characterization, as well as the design and synthesis of biobased monomers and polymers. His work involves the development of valorization methods for converting agricultural and agroforestry waste – specifically lignin – to value added compounds, which can be used as building blocks in the polymer and pharmaceutical industries. Ndumiso has also developed unique skills in biorefinery development.

Employed at Afriplex, Paarl, South Africa.


Dr. Anthony Ndiripo

Anthony is a Postdoctoral Researcher at the Department of Chemistry and Polymer Science in Stellenbosch, South Africa, as well as an Alexander von Humboldt Researcher at the Center for Macromolecular Structure Analysis in Dresden, Germany. He has more than eight years of polyolefin characterization research and industrial collaboration experience, and has a keen interest in the conscientious application of this knowledge Anthony’s research interests include development of new characterization protocols, as well as improving existing techniques for polyolefin characterization. He is highly skilled in high-temperature techniques such as size exclusion (SEC) and interaction chromatography (IC), crystallization analysis and elution fractionation (CRYSTAF and CEF), temperature rising elution fractionation (TREF) and molar mass fractionation (MMF).


Employed at SABIC, Geleen, The Netherlands.



Natalia Makarova

Natalia received her Bachelor degree in Radiophysics from Saratov State University, Russia in 2019 and has complted a Master degree within the BIOTEC Nanobiophysics programme of the Technische Universität Dresden. Natalia’s interests were in the area of the physicochemical understanding of nanoparticle-drug delivery for malaria treatment and the development of novel physical approaches for the analysis polymer-drug conjugates via field flow fractionation.


Max Palinske

Max completed a Master degree at the Technische Universität Dresden and IPF and focused on the microstructural analysis of stimuli responsive polymersomes using AF4 and SANS. He was furthermore interested in their self-assembly and the conformation effects during the processes of protein encapsulation and release.


Beate Marchlewski

Beate Marchlewski was an assistant at the Centre for Macromolecular Structural Analysis (MSA) since 1991 and was responsible for organizing Prof. Albena Lederer’s secretariat as well as supporting the staff of the working groups at MSA in all organizational areas.

Dr. Shamila Firdaus

Shamila studied Chemistry at the IT in Kharagpur, India. After her Master work at IPF and IIT within a DAAD programme, she recived the SMWK award for her PhD studies at the IPF. Shamila looked into the synthesis of novel dendritic architectures and their functionalization for application in polymer-protein interactions. She attained her PhD when she investigated the activity of pseudodendrimers against Alzheimer amyloid formation using complementary analytical and theoretical methods like AF4, MD simulation, CD and electron microscopy. Shamila is keen on understanding the kinetics of protein aggregation using advanced analytical techniques.