Principal Investigator

Jeroen Rouwkema is an Associate Professor in the Department of Biomechanical Engineering at the University of Twente. Jeroen received his doctoral degree from the University of Twente under the supervision of prof. Clemens van Blitterswijk. Prior to this, he worked 6 months in the lab of prof. Robert (Bob) Langer at MIT, USA. Between 2014 and 2015 he was also appointed as a Visiting Researcher at Harvard Medical School, USA, in the group of Prof. Ali Khademhosseini.

His expertise and interests are tissue engineering, vascularization, and the role that biomechanical signals play in these processes. Additionally, he focuses on engineering tools to tune the cellular environment including embedded bioprinting approaches. He has published in multiple high-impact journals, including Nature Biotechnology (IF 41.5), Advanced Materials (IF19.0), TRENDS in Biotechnology (4x, IF 12.0), and PNAS (2x, IF 9.7). He has directed approximately € 3 million in research funding.

Jeroen has received a VENI fellowship from NWO, as well as an International Outgoing Fellowship, which is part of the Marie Skłodowska-Curie actions of the European Commission. In 2017 he received a European Research Council (ERC) Consolidator grant and in 2019 and 2021 an ERC Proof of Concept grant. He is also Work Package leader in the FET Open project APRICOT. In 2017 he received the TERMIS EU Robert Brown Early Career Principal Investigator Award.


E-mail: j.rouwkema@utwente.nl

Post-doctoral fellows

Vasileios Trikalitis (1990) obtained his bachelor degree in Material Science at the University of Patras in 2014. His thesis focused on the creation and confinement of molecular structures inside carbon nanotubes. In 2016 he obtained his Master’s degree in Biomedical Engineering with a specialization in Tissue Regeneration and Bionanotechnology. His thesis was completed in the DBE (Developmental Bio Engineering) at the University of Twente in collaboration with the POF (Physics of Fluids) group. The focus of the thesis was the development of a novel 3D bioprinting technique named In Air Microfluidics (IAMF) which combined microfluidics and 3D printing principles with an aim to produce a tissue reconstruction platform. He has also worked as a research intern in the Danish Technical University (DTU) on the creation of cell-mimicking organelles that can conduct cascade reaction for the purpose of theranostics.

In 2017, he started as a PhD student in the Biomechanical Engineering department under the supervision of Prof. Jeroen Rouwkema. His research focuses on the development of vascular networks in artificial tissue constructs, using 3D (bio)printing approaches.


E-mail: v.trikalitis@utwente.nl

Previous members



Ajoy Kandar is presently working as a postdoctoral fellow ( from October 2019) in the Department of Biomechanical Engineering under the mentorship of Dr. Rouwkema with some close collaboration with Dr. Visser and Prof. Luding. His research focuses on understanding the structure and flow behavior of bio-ink and optimize it for 3D printing.

Ajoy received his Bachelor degree and Master degree in physics from University of Calcutta, India. He obtained his Doctoral Degree (PhD) in experimental soft condensed matter physics with the thesis title as “Slow Dynamics in Complex Fluids: Confined Polymers and Soft colloids”, from the Indian Institute of Science (IISc), Bangalore, India in March 2013. The focus of his PhD work was centered on two aspects : (a) experimentally (combining two novel technique, Langmuir Blodgett films and confocal microscopy) understanding viscoelasticity, dynamical heterogeneity, finite-size effects and glass transition of nano-confined polymer systems at water-air interface using particle tracking methods, (b) experiments on the suspensions of soft colloidal particles (polymer grafted nano-particles) in melts and solution to understand their interesting structures, fascinating dynamics, and phase behavior using SAXS and XPCS techniques in the international synchrotron facilities available in Argonne National Laboratory, USA and the DESY laboratory, Germany.

After PhD, he started 1st post-doc ( in March 2013) at IISc in a lab that routinely uses bulk and interfacial rheology along with imaging techniques in order to gain shear-induced structural changes and its inherent physics. During this time (for three years) at IISc, he worked closely with Prof. Ajay K. Sood, he extended his experiences by developing skills in interfacial rheology combining with imaging techniques, developed a deep understanding of interfacial rheology methods particularly creep, large amplitude oscillatory shear (LAOS) and yielding of interface films. He acquired skills in Rheo-GIXD technique (in SOLEIL, France) which allows studying very precisely structure of the molecularly thin membrane and structural transition upon application of shear. He also was involved in understanding shear-induced structural transition in the surfactant system using Rheo-SAXS measurement in DESY laboratory, Germany and in experimentally studying phase behavior of self-propelled nematic droplets. He received Dr. DSKothari postdoctoral fellowship during this time.

After that he moved to University of Utrecht, the Netherlands for his 2nd postdoc (in April 2016) in the SCM group where he worked closely with Prof. van Blaaderen for more than three years on several projects as follows: (a) he studied the non-equilibrium phase behavior of long-ranged repulsive colloids under oscillatory shear using confocal microscopy coupled with the shear cell, (b) he designed and developed smart light switchable active colloids (with collaboration with PhD student) to study active particles (both spherical and rod-like). He used a state of the art confocal microscopy and particle tracking to study concentrated systems on the single-particle level. He also was focused on activity-induced crystallization of passive colloids in both 2D and 3D. (c) He also concentrated on studying 3D force network and force anisotropy in closed packed jammed elastic particles in 3D under simple shear.

His expertise and interests are in soft matter and biological model systems, and especially in self-assembly, crystallization, crystal melting, phase behaviour of self-propelled colloids, rheology (bulk and interface) of complex fluids, nano & microscale imaging (2D and 3D), glass and jamming transition, phase behavior of soft-nano colloids, dispersion of smart colloids and their various interactions, active emulsion fluids, the structure of surfactant and biological (lipid and protein) monolayer, coherent x-ray scattering and imaging, synthesis of colloidal systems etc.


E-mail: a.k.kandar@utwente.nl

Nasim Salehi-Nik (1984) obtained her bachelor and master degrees in Chemical Engineering at the University of Tehran. In 2009 she started her PhD under a dual degree program with the University of Tehran and VU University Amsterdam. During her PhD study, she developed a flow-resistant and anti-thrombotic functional endothelial cell layer on the surface of silicone hollow fibers using silicone surface modification and fluid hydrodynamics modulation to improve the biocompatibility of artificial lungs. In the meantime, she gained knowledge of regenerative medicine through working on different projects with particular experience on biomimetic coatings, bioreactor design and computational approaches in bioreactors to model mass transfer and mechanical forces. In 2015 she started a postdoctoral position at Shahid Beheshti University of Medical Sciences in which she worked on pre-vascularization of bone tissue-engineered grafts

In 2017, she started as a postdoc in the Biomechanical Engineering department under the supervision of Prof. Jeroen Rouwkema. Her research focuses on the development of vascular networks in artificial tissue constructs.


E-mail: n.salehinik@utwente.nl

Doctoral candidates

Mira El Akkawi (1996) obtained her bachelor’s degree in chemistry at the University of Saint-Joseph in Beirut - Lebanon. In 2017, she moved to Bordeaux - France to complete her Master’s degree in Chemical Physics engineering with a specialization in Advanced Materials and Processes. She obtained her diploma in 2020.

Throughout her studies, she did a research internship (2019) at the Luxembourg Institute of Research and Technology - LIST on the development of a high-performance polymer nanocomposite with electro-conductive properties for space applications. Her master’s thesis (2020) was done at the company GRADEL in Luxembourg and was focused on the optimization of a newly developed filament winding process to produce ultra-light-weight composite structures. She was afterwards hired by the same company as a Materials Engineer and was responsible for overseeing R&D projects as part of the space qualification of the endless filament winding process developed in-house.

In 2022, she started her PhD in the Design, Production and Management department in collaboration with the Engineering Organ Support Technologies department under the supervision of Prof. Ian Gibson, Prof. Jeroen Rouwkema and Dr. Constantinos Goulas. Her research focuses on the application of local mechanical stimulation on 3D-(bio)printed constructs inside a granular gel supporting medium.


E-mail: m.elakkawi@utwente.nl
Pardis Farjam (1992) is currently working as a PhD student in the Department of Biomechanical Engineering under the supervision of Prof. Bart Verkerke, co-supervised by Jeroen Rouwkema. Her research focuses on the development of a novel minimally invasive joint implant.

Pardis received her BS. Degree (2010) in Mechanical Engineering from Shiraz University. She joined Shiraz University (2014-2015) as junior researcher. She mainly worked on computational biofluid mechanics, simulation and tracking of aerosols in respiratory system. In 2018, she obtained her Master’s degree in Biomedical Engineering from Polytechnic of Milan with specification of Biomaterials and Biomechanics. During her Master thesis, she worked on performing a novel multistep surface coating on Magnesium alloy which can be utilized as biocompatible biodegradable implants in different sectors such as cardiovascular stents and orthopedic implants. She used MAO/EPA technology to create the desired coating on Magnesium to decrease its degradation rate in order to support the tissue for the needed period of healing time. The risk of cytotoxicity induced by the surface treatment was evaluated by the alamarBlue® Assay.

During her internship at University of Melbourne (2018), she mainly focused on melt electrospinning of natural polymer blends as main constituent of cartilage extracellular matrix. She exploited the capacity of collagen and elastin to construct 3D printed scaffolds.
E-mail: p.farjam@utwente.nl
Prasanna Padmanaban is currently a final year PhD candidate in the Department of Biomechanical Engineering under the supervision of Dr. Jeroen Rouwkema. Prasanna received his Master’s degree with Honors from Friedrich Alexander University Erlangen-Nuremberg, Germany. During his master’s, he worked in the lab of Prof. Philip Russell at Max Planck Institute for the Science of Light (MPL), Erlangen and for thesis assignment, in the lab of Dr. Moritz Kreysing at Max Planck Institute of Molecular Cell Biology and Genetics (MPI-CBG), Dresden.

Prasanna has received Erasmus Traineeship abroad scholarship for which he worked at UCB, Belgium. At UCB, he also received an Focused Recognition Award for enabling his team to make data-driven decision on the cell line assessment study. In 2019, he represented University of Twente at Utrecht for FameLab National Finals, a popular international science communication competition.

For his PhD Project, Prasanna is working towards creating efficient engineering tools to probe, perturb and predict the evolution of vascular networks in invivo, invitro and insilico models. He focuses on three main topics;
1. Understanding the vascular development processes in the developing chicken embryo using multi-mode imaging
2. Tuning the vascular network and organization using external localized fluid flows and geometrical shapes
3. Predicting the evolution of vascular network types using computational models and Artificial Intelligence (AI), when different mechanical and chemical signals are applied

He supervised 4 Bachelor thesis and 2 Master thesis assignments. Apart from research, Prasanna appreciate and participate in public speaking and science communication events (like FameLab, Science Cafe) to promote science to the general audience and being creative when it comes to cooking, drawing and making crafts from recycled items. As an outgoing person, he also enjoy organizing social events and very active in Twitter.
E-mail: p.padmanaban@utwente.nl
Website: www.prasanna.biz
Deepti Rana (1991) obtained her B. Tech and M. Tech degree in Nanotechnology at the Amity University, India. In 2014, she started working as a Research Fellow at the Centre for Stem Cells Research, Christian Medical College, Vellore, India. During this period, she mainly worked for the development of multi-scale (nano to micro to macro) biomaterials for the translational stem cell research, stem cell nanotechnology, tissue engineering and nanomedicine. She has developed different types of cell-laden hydrogel systems, such as cryogels (shape memory) and thermogels (injectable) suitable for the 3D culture of human bone marrow derived mesenchymal stem cells. Additionally, she has worked for the development of gradient hydrogel systems (stiffness and biomolecular gradients) for the high throughput screening of stem cells. She has published her research work in several peer-review journals, book chapters and conferences.

In 2017, she started as a PhD student in the Biomechanical Engineering department under the supervision of Prof. Jeroen Rouwkema. Her research focuses on the patterning of growth factors in space and time via hydrogel modifications for vascular tissue engineering.
E-mail: d.rana@utwente.nl
Fabian Stein (1986) obtained his bachelor degree in Bioscience with specification in Molecular Biology and Physiology at the University of Potsdam in 2012. In his bachelor thesis at the Institute for biochemistry and biology he focused on the catalytic parameters of the two starch iso-branching enzymes AtBE2 and AtBE3. During his master he worked in different projects e.g. at the Berlin-Brandenburg-Centrum for regenerative therapies (BCRT) where he analyzed the immune competence of iPSCs and iPSC-derived cells. In 2015 he obtained his Master’s degree in Molecular Life Science with a specification in Medical Cell Biology at the University of Lübeck. For his thesis he worked in the biotech company co.don AG who are specialized in the regeneration of articular cartilage. He analyzed the mechanism of the self- adhesion abilities of their autologous cartilage 3D cell transplant chondrosphere®. After that, he worked in the Organ-on-the-Chip company TissUse GmbH to establish protocols for iPSC-derived endothelial cells among other things.

In 2017, he started as a PhD student in the Biomechanical Engineering department under the supervision of Prof. Jeroen Rouwkema. His research focuses on the effect of fluid flow profiles on the development and organization of vascular networks in artificial tissue constructs.
E-mail: f.stein@utwente.nl

Jiena Zhang (1988) obtained her bachelor’s degree in Bioengineering in 2010 in China. In 2013 She started her Masters studying in Bioengineering in The University of Nottingham, where she did her final dissertation as part of a PhD project. In this project she was focusing on developing and testing bioreactors for perfusing culture of 3D tissue scaffolds. In 2015, she started working at Professor Nicola Elvassore’s lab at Shanghai Institute of Advanced Immunochemical Studies (SIAIS) at ShanghaiTech University. She was responsible for the designing and fabrication of the microfluidic chips for several applications in the lab. At the same time she was working on a project which was in collaboration with Dr. Richard A. Lerner’s group based at SIAIS, which involves using and developing mcirotechnologies for high-throughput screening of antibody library.

In 2017, she started as a PhD student in the Biomechanical Engineering department under the supervision of Prof. Jeroen Rouwkema. Her research focuses on the development of vascular networks in artificial tissue constructs using tissue building block approaches.
E-mail: j.zhang-6@utwente.nl



Previous members



Vasileios Trikalitis (1990) obtained his bachelor degree in Material Science at the University of Patras in 2014. His thesis focused on the creation and confinement of molecular structures inside carbon nanotubes. In 2016 he obtained his Master’s degree in Biomedical Engineering with a specialization in Tissue Regeneration and Bionanotechnology. His thesis was completed in the DBE (Developmental Bio Engineering) at the University of Twente in collaboration with the POF (Physics of Fluids) group. The focus of the thesis was the development of a novel 3D bioprinting technique named In Air Microfluidics (IAMF) which combined microfluidics and 3D printing principles with an aim to produce a tissue reconstruction platform. He has also worked as a research intern in the Danish Technical University (DTU) on the creation of cell-mimicking organelles that can conduct cascade reaction for the purpose of theranostics.

In 2017, he started as a PhD student in the Biomechanical Engineering department under the supervision of Prof. Jeroen Rouwkema. His research focuses on the development of vascular networks in artificial tissue constructs, using 3D (bio)printing approaches.
E-mail: v.trikalitis@utwente.nl

Master's degree students

Alba Rivera (1998) is a biomedical engineer graduated in 2021 from the University Rey Juan Carlos in Madrid, Spain. During her Bachelor, she did an internship at INKA, a company associated to the University of Magdeburg, Germany. She carried out a machine learning project for the segmentation of ultrasound images of the spinal bone. Her bachelor's thesis was focused on surface engineering in magnesium alloys for biomedical applications.

After that, she started her Master's degree in Bioengineering Technologies at the University of Twente (UT). During her Master, she worked at VyCAP, a spin-off company founded from the research group Medical Cell BioPhysics of the UT. Her main work was based on setting up and optimizing the workflow for PSA secretion of LNCaP cells and IgG detection using PVDF membranes.

She is currently doing her Master's thesis in the biomechanical engineering department under the supervision of Mira El Akkawi. Her research focuses on magnetic bioinks based on hydrogels with embedded iron particles that allow their deformation, which could be used as a mechanical stimulation when in combination with cells.




Previous members



Vincent Rangel (1999) obtained his bachelor degree in Biomedical Engineering at the University of Twente in 2019. His bachelor thesis was conducted at Vascularization Lab, under supervision of Vasileios Trikalitis, and was devoted to the creation of a 3D bioprinted environment for vascularization by printing patterned, aptamer-functionalized GelMA with HUVECs to obtain spatiotemporal cell growth. The experience with bioprinting and theoretical implementation of vascularized engineered tissue led to his interest in Tissue Engineering and 3D bioprinting in general. During his bachelor, he took additional interest in design and human interaction at the Technische Universiteit Eindhoven.

In 2020, he started his masters in Biomedical Engineering at the University of Twente, focussing on the Bioengineering Technologies track and having additional courses in fluid mechanics and microfluidics. He has fulfilled extended experiments involving bioprinting for Vascularization Lab in cooperation with Deepti Rana during his masters. His master’s assignment will also be conducted at Vascularization Lab involving 3D bioprinting.


Marta Sacchi obtained her bachelor’s degree in Biomedical Engineering at the Polytechnic University of Milan with a thesis on the development of a MATLAB Graphical Visualization Tool for the analysis of multiparameter cerebral data. After her Bachelor, in order to gain further experience in the connection between cell biology and engineering science, she attended a training course on 3D cell culture and bioprinting at the University of Milan (MSc in Veterinary Biotechnology Sciences) as part of the EU COST Action “CellFit”. In 2018 she started her master’s degree in Biomedical Engineering at the University of Twente, majoring in the Bioengineering Technologies track. In 2019, as part of the Master program, she worked 6 months as research intern in the Stem Cell Mechanobiology Lab at the University of Western Australia (Perth), developing novel gradient stiffness hydrogel platforms for 3D cancer mechanobiology. She is currently pursuing her Master thesis in the Vascularization Lab in a collaboration with Dr. Ruchi Bansal (Translational Liver Research Lab), under the supervision of Fabian Stein. Her project focuses on the development of a vascularized liver lobule on a chip for the study of the effects of the matrix mechanical properties on tissue fibrosis development and functioning.
Marco Nicolai Stimac (1993) obtained his bachelor’s degree in Medical Engineering Science at the University of Lübeck in 2017. In his thesis at the Institute of Physics he purified porcine brain microtubules and investigated their dynamic instability by using fluorescence microscopy, transmission electron microscopy and small-angle X-ray scattering under the supervision of Prof. Dr. Christian Hübner and Dr. Young-Hwa Song. From 2017 to 2018 he studied Biophysics at the University of Lübeck for two semesters and performed protein purification as a scientific assistant at the Institute of Physics.

In 2018 he started his master’s degree in Biomedical Engineering at RWTH Aachen University and is now performing his internship at the Vascularization Lab under the supervision of Vasileios Trikalitis. In his project he is evaluating the effect of different embedding bath materials on HUVEC and SMC spheroids using suspension bioprinting.


Maud Kerstholt obtained her bachelor degree at Utrecht University / UMC Utrecht. For her bachelor thesis, she studied the role of the immune system in (pathological) bone remodelling. In order to be able to better study the complexity of such processes, she decided in 2017 to continue her studies with a master Bioinformatics at Wageningen University & Research. To keep the link to her biomedical interests, she added her second master in Regenerative Medicine & Technology at the Graduate School of Life Sciences of Utrecht University in 2018. She collaborates with the lab of Jeroen Rouwkema for her bioinformatics master thesis, under supervision of Prasanna Padmanaban. In this project, she will use computer models to study the endothelial cell response to chemical and mechanical stimuli.





Hi I’m Martin Leonhardt, a biomedical engineering student at the vascularization lab of the biomechanical engineering group. In my master’s assignment I am trying to point out the influences of certain shapes (diameter, curvature, branching, etc.) of blood vessels on the development of new sprouts – called angiogenesis.

In 2017 I carried out my internship at the Department of Biosystems Science and Engineering of the ETH Zurich, analyzing Schistosoma m. on a microfluidic platform in collaboration with the Swiss Tropical and Public Health Institute.

In my former position, till August 2015, I was working as a test engineer for Dresden MOS design GmbH. I was responsible for the development of test hard- and software for automotive ICs (integrated circuits) and for the standardization of those tasks on a specific test platform (T2000) – no, not the liquid metal assassin (T1000) from Terminator 2 – Judgement Day.

I received my first degree in electrical engineering (Dipl.-Ing. (FH)) in 2011 from the University of Applied Sciences in Dresden (HTW Dresden), while working at the Klippel GmbH – a specialist for audio R&D and mass production measurement kits.

My general interests are related to all sorts of engineering disciplines and natural sciences, but also more and more metal machining. Apart from that I appreciate dancing as a member of Arabesque (Modern Dance) and being creative when it comes to cooking and baking. Of course I also like to share my prepared stuff with friends and colleagues.

Julia Perea Paizal (1993) finished her Bachelor in Biomedical Engineering at the University of Málaga (Spain). Her Bachelor’s Thesis focused on the modeling of the neuronal circuit of the reflex arc using block-oriented programming techniques. During her Bachelor, she worked in the medical company Macrimasa-Pharma focusing on the research and validation of electro medical equipment. After that she did an internship in the University of Lüneburg (Germany), working in the micro and nano characterisation of micro fibres for biomedical applications.

In 2016 she started a Master’s degree in Biomedical Engineering in the UT with a specialization in Bionanotechnology and Advanced Biomanufacturing. During her Master, she was a research intern at NIFE institute (Hannover, Germany), investigating the properties of decellularised porcine pericardium scaffolds for tissue engineered heart valves replacements. She is currently pursuing her Master thesis in the Vascularization Lab, where her research focuses on the induction of angiogenesis through suspension bioprinting.


Denise Marrero (1993) finished her Bachelor in Biomedical Engineering at Polytechnic University of Catalonia (UPC) in 2016. As a bachelor student, she developed a therapeutic app to rehab patients with neuronal disorders. While finishing her degree, she worked as a Biomedical Technician at two hospitals in Barcelona.

In 2017, she started a Master program at the University of Twente and she is currently studying Biomedical Engineering with the specialization track of Bionanotechnology and Biomanufacturing. Nowadays, she is collaborating with Vascularization Lab under the supervision of Fabian Stein. Her interest is to study the influence of mechanical stimulation on cardiomyogenic differentiation.



Gary Shea (1994) finished his bachelor in 2016 at Rensselaer Polytechnic Institute in NY, USA. In his bachelor, he studied biomedical engineering and participated in research investigating transient disruption of tight junctions in the blood-brain barrier. His interest later focused on development of a dynamic culture system incorporating shear stress to human brain microvascular endothelial cells to create barrier properties more representative of the physiological environment. Upon graduation, he worked as a research technician at MIT in a laboratory focused on single-cell RNA sequencing technology. He is currently pursuing a master's degree in biomedical engineering. In the Vascularization lab, Gary is interested in cellular self-organization and scaffold-free tissue engineering.





Ana Luísa Silva (1995) is a Biomedical Engineering student from the University of Minho, Portugal, currently finishing her Master’s Degree in Biomaterials, Rehabilitation and Biomechanics. At the 3B’s Research Group she started the development of her master project working on the potential of hyaluronic acid oligomers for vascularization in tissue engineering. She started working at the Vascularization Lab in February 2018 as part of her student exchange at the University of Twente, under the daily supervision of Deepti Rana. Her project consists of optimizing and evaluating cell response to modified hyaluronic acid coatings for the promotion of angiogenesis, as well as creating cell guiding patterning approaches. After finishing her project in June 2018, she will return to the 3B’s Research Group and to the University of Minho to finish her studies.




In 2016, Chiara Trenti (1994) finished her bachelor degree in Biomedical engineering at the Politecnico di Milano. For her bachelor thesis at the “Giulio Natta” Chemistry, Material and Chemical Engineering Department, she worked on the reconstruction of the nuclear envelope by the manual segmentation of transmission electron microscopy (TEM) images and studied the mechanical deformation of the nuclear pores, both in cells attached and in suspension. After that, she started her Master degree in Biomedical engineering with specialization in Biomechanics and Biomaterial at the Politecnico di Milano. As part of her student exchange at the University of Twente, she started her research project in the Vascularization Lab under the daily supervision of Fabian Stein in October 2017. Her project focuses on the effects of different fluid flow profiles on endothelial cells in microfluidic chips. After finishing her project in February 2018, she will go back to Milan to complete her studies.