A5090022001- Electrospun Nanofibers in Biomedical Applications
- Additive Manufacturing and 3D Printing Technologies
- 3D Printing in Biomedical Research
- Advanced Sensor and Energy Harvesting Materials
- Tissue Engineering and Regenerative Medicine
- Neuroscience and Neural Engineering
- Recycling and Waste Management Techniques
- Nanomaterials and Printing Technologies
- Conducting polymers and applications
- Microfluidic and Bio-sensing Technologies
- Electrohydrodynamics and Fluid Dynamics
- Cardiac electrophysiology and arrhythmias
- Graphene and Nanomaterials Applications
- Immune cells in cancer
- Electrodeposition and Electroless Coatings
- Renal and related cancers
- Electrowetting and Microfluidic Technologies
- Innovative Microfluidic and Catalytic Techniques Innovation
- Material Selection and Properties
- Pluripotent Stem Cells Research
- Photonic and Optical Devices
- Advanced Materials and Mechanics
- Innovations in Concrete and Construction Materials
- Mesoporous Materials and Catalysis
- Planarian Biology and Electrostimulation
Utrecht University
2020-2024
University Medical Center Utrecht
2020-2024
Bavarian Polymer Institute
2017-2021
University of Würzburg
2021
Universitätsklinikum Würzburg
2016-2019
The electrohydrodynamic stabilization of direct-written fluid jets is explored to design and manufacture tissue engineering scaffolds based on their desired fiber dimensions. It demonstrated that melt electrowriting can fabricate a full spectrum various fibers with discrete diameters (2-50 µm) using single nozzle. This change in diameter digitally controlled by combining the mass flow rate nozzle collector speed variations without changing applied voltage. greatest was achieved simultaneous...
Abstract Additive manufacturing with electrohydrodynamic direct writing is a promising approach for the production of polymeric microscale objects. In this study we investigate stability one such process, melt electrospinning writing, to maintain accurate placement deposited fibre throughout entire print. The influence acceleration voltage and feeding pressure on poly(ε-caprolactone) homogeneity described, how affects variable lag jet drawn by collector movement. Three classes diameter...
Abstract Macrophages are key players of the innate immune system that can roughly be divided into pro-inflammatory M1 type and anti-inflammatory, pro-healing M2 type. While a transient initial state is helpful, prolonged inflammation deteriorates proper healing subsequent regeneration. One promising strategy to drive macrophage polarization by biomaterials precise control over biomaterial geometry. For regenerative approaches, it particular interest identify geometrical parameters direct...
Melt electrowriting, a high-resolution additive manufacturing technology, has so far been developed with vertical stacking of fiber layers, printing trajectory that is constant for each layer. In this work, microscale layer shifting introduced through deliberately offsetting the printed Inaccuracies during sinusoidal walls are corrected via shifting, resulting in accurate control their geometry and mechanical properties. Furthermore, more substantial allows layers horizontal manner,...
Abstract Fused silica glass is the preferred material for applications which require long-term chemical and mechanical stability as well excellent optical properties. The manufacturing of complex hollow microstructures within transparent fused particular interest for, among others, miniaturization synthesis towards more versatile, configurable environmentally friendly flow-through chemistry high-quality waveguides or capillaries. However, microstructuring such three-dimensional structures in...
Abstract One challenge in biofabrication is to fabricate a matrix that soft enough elicit optimal cell behavior while possessing the strength required withstand mechanical load subjected once implanted body. Here, melt electrowriting (MEW) used direct‐write poly(ε‐caprolactone) fibers “out‐of‐plane” by design. These out‐of‐plane are specifically intended stabilize an existing structure and subsequently improve shear modulus of hydrogel–fiber composites. The stabilizing (diameter = 13.3 ± 0.3...
Abstract Melt electrowriting (MEW), an electrohydrodynamic additive manufacturing technology, can produce polymer structures with micrometer resolution. Unlike conventional direct writing of fluids, the laydown pattern often deviates from programmed one, due to a lag in electrified jet. MEW increasingly complex patterns currently entails cumbersome trial‐and‐error procedure adjusting printing parameters ensure good accuracy. This issue is addressed geometrical model that predicts expected...
Abstract Melt electrowriting (MEW) is an additive manufacturing technology that recently used to fabricate voluminous scaffolds for biomedical applications. In this study, MEW adapted the seeding of multicellular spheroids, which permits easy handling as a single sheet‐like tissue‐scaffold construct. Spheroids are made from adipose‐derived stromal cells (ASCs). Poly(ε‐caprolactone) processed via into with box‐structured pores, readily tailorable spheroid size, using 13–15 µm diameter fibers....
Abstract Melt electrospun fibers, in general, have larger diameters than normally achieved with solution electrospinning. This study uses a modified nozzle to direct‐write melt medical‐grade poly(ε‐caprolactone) onto collector resulting fibers the smallest average diameter being 275 ± 86 nm under certain processing conditions. Within flat‐tipped is small acupuncture needle positioned so that reduces flow rate ≈0.1 µL h −1 and has sharp tip protruding beyond nozzle, into Taylor cone. The...
Abstract Melt electrowriting (MEW) is a direct‐writing technology for small diameter fibers; however, due to electrostatic attraction, the technique restricted in how close these microfibers can be positioned on collector. Here, minimum interfiber distance between parallel poly(ε‐caprolactone) MEW determined different fiber diameters and number of layers noncoated star‐shaped poly(ethylene oxide‐ stat ‐propylene oxide) (sP(EO‐ ‐PO))‐coated glass coverslips. The effect diameter, layers, shape...
Abstract To progress cardiac tissue engineering strategies closer to the clinic, thicker constructs are required meet functional need following a event. Consequently, pre-vascularization of these needs be investigated ensure survival and optimal performance implantable engineered heart tissue. The aim this research is investigate potential combining extrusion-based bioprinting (EBB) melt electrowriting for fabrication myocardial construct with precisely patterned pre-vascular pathway....
Melt electrowriting is an AM technology that bridges the gap between solution electrospinning and melt microextrusion technologies. It can be applied to biomaterials tissue engineering by making a spectrum of scaffolds with various laydown patterns at dimensions not previously studied. Using submicrometer X-ray tomography, "fingerprint" porosity for such obtained used as important measure quality control, ensure scaffold fabricated one designed allows selection specific based on desired porosities.
Abstract Melt electrowriting (MEW) is a high‐resolution additive manufacturing technology that places unique constraints on the processing of thermally degradable polymers. With single nozzle, MEW operates at low throughput and in this study, medical‐grade poly(ε‐caprolactone) (PCL) heated for 25 d three different temperatures (75, 85, 95 °C), collecting daily samples. There an initial increase fiber diameter decrease jet speed over first 5 d, then process remains stable 75 85 °C groups....
Abstract 2D electrophysiology is often used to determine the electrical properties of neurons. In brain however, neurons form extensive 3D networks. Thus, performing in a environment provides closer situation physiological condition and serves as useful tool for various applications field neuroscience. this study, established within fiber‐reinforced matrix enable fast readouts from transfected cells, which are model systems electrophysiology. Using melt electrowriting (MEW) scaffolds...
The development of in vitro assays for 3D microenvironments is essential understanding cell migration processes. A 3D-printed competitive radial device developed to identify preferred Matrigel concentration glioblastoma migration. Melt electrowriting (MEW) used fabricate the structural with defined and intricate structures that are filled Matrigel. Controlling printing path necessary account distance lag molten jet, applied electric field, continuous direct-writing nature MEW. Circular below...
Engineered heart tissues (EHTs) built from human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) showed promising results for cardiac function restoration following myocardial infarction. Nevertheless, iPSC-CMs have longer action potential and lower cell-to-cell coupling than adult-like CMs. These immature electrophysiological properties favor arrhythmias due to the generation of gradients when hiPSC-CMs are injected in tissue. Culturing on three-dimensional (3D) scaffolds...
In this study, well-defined, 3D arrays of air-suspended melt electrowritten fibers are made from medical grade poly(ɛ-caprolactone) (PCL). Low processing temperatures, lower voltages, ambient temperature, increased collector distance, and high speeds all aid to direct-write suspended that can span gaps several millimeters between support structures. Such parameters quantitatively determined using a "wedge-design" test frame identify the conditions increase suspension probability...
Abstract Polymers sensitive to thermal degradation include poly(lactic‐ co ‐glycolic acid) (PLGA), which is not yet processed via melt electrowriting (MEW). After an initial period of instability where mean fiber diameters increase from 20.56 27.37 µm in 3.5 h, processing stabilizes through 24 h. The jet speed, determined using critical translation speed measurements, also reduces slightly this h 500 433 mm min −1 but generally remains constant. Acetyl triethyl citrate (ATEC) as additive...
Event Abstract Back to Electrospinning and direct writing: why polymer melts are excellent fluids for 3D printing Paul Dalton1, Tomasz Jungst1, Almoatazbellah Youssef1, Andrei Hrynevich2, Gernot Hochleitner1 Jürgen Groll1 1 University of Würzburg, Functional Materials in Medicine Dentistry, Germany 2 RWTH Aachen, Biomedical Engineering Science, Introduction: Many different have been used with nozzle-based writing techniques, including polyelectrolytes, colloidal inks, hydrogel inks...
Abstract A novel approach merging melt electrowriting (MEW) with matched die thermoforming to achieve scaffolds micron‐sized curvatures (200 – 800 µm versus 1000 of mandrel printing) for in vitro modeling the kidney proximal tubule (PT) is proposed. Recent advances this field emphasize relevance accurately replicating intricate tissue microenvironment, particularly curvature nephrons’ tubular segments. While MEW offers promising capabilities fabricating highly and porous precise 3D...
Event Abstract Back to Continuous 3D printing of different diameter microscale poly(ε-caprolactone) filaments Paul Dalton1, Bilge Şen Elçi2, Andrei Hrynevich3, Carina Blum1, Tomasz Jungst1, Gernot Hochleitner1 and Jürgen Groll1 1 University Würzburg, Functional Materials in Medicine Dentistry, Germany 2 İstanbul Bilgi University, Genetics Bioengineering, Türkiye 3 RWTH Aachen, Biomedical Engineering Science, Introduction: Additive manufacturing via melt direct writing has limits on the...
Introduction: Advances in material science and cell technology offer new possibilities myocardial repair. We test the safety feasibility of implanting epicardial cellularized patches a porcine ischemic cardiomyopathy model, representative human disease. Methods: In pigs (n=4) , 90 min occlusion circumflex artery induced infarction (MI) (infarct size at 4w MRI: 16±7% LV mass with reduced EF 49±12%). To cover scar, hexagonal multi-layered 4x4cm scaffolds were printed using high-resolution 3D...