Dorothea Helmer, Dr. rer. nat.
Postdoc
Department of Microsystems Engineering (IMTEK)
Albert-Ludwigs University of Freiburg
Georges-Köhler-Allee 103 | 79110 Freiburg im Breisgau | Germany
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Curriculum Vitae
Professional experience
- since 10/2020: Group leader at FMF of the BMBF NanoMat Futur Research Group "MatrixPrint"
- since 10/2014: Postdoc at the NeptunLab
- 2009 - 2014:PhD thesis (Dr. rer. nat. final grade: 1.0, organic chemistry and biochemistry),Synthesis and Test of Peptides and Peptoids for the Inhibition of Cytokines, Prof. Katja Schmitz (Technical University of Darmstadt TUD)
- 2004 - 2009: Studies in chemistry (University of Karlsruhe), final grade: 1.2
Awards
- 2021 Lothar Späth Award for Glassomer GmbH
- 2019 Technology Transfer Prize for Glassomer GmbH, KIT, Karlsruhe
- 2019 Start-Up Award Rapid Tec for Glassomer GmbH
- 2019 Freiburger Innovation Award for Glassomer GmbH
- 2019 Start-Up Award of Formnext for Glassomer GmbH
- 2019 2nd place Start-Up-BW finals for Glassomer GmbH, Stuttgart
- 2018 SPIE Photonics West Startup Challenge Finalist
- 2012 Winner Fame Lab Baden-Württemberg
Publications
Journal Papers
N. Nekoonam, F. Dreher, F. Mayoussi, P. Zhu, R. Thomann, R. Montazeri, S. Bhagwat, L. Hambitzer, D. Helmer*, Enhancing Photoswitchable Wetting Properties of Hydrophobic Porous Spiropyran Copolymer Surfaces Through Surface Roughness Engineering, Adv. Mater. Interfaces 2024, 11, 2400396 | Link
D. Böcherer, R. Montazeri, Y. Li, S. Tisato, L. Hambitzer, D. Helmer, Decolorization of Lignin for High-Resolution 3D Printing of High Lignin-Content Composites, Advanced Science, 2024, 202406311. Link
D. Böcherer, Y. Li, S. Kluck, N. Nekoonam, P. Zhu, B. E. Rapp, F. Kotz-Helmer, D. Helmer, COLOR3D – Multicolored 3D printing of wood composites by submicron structuring, Addit. Manuf., 2023, 75, 103723 l Link
N. Nekoonam, G. Vera, A. Goralczyk, F. Mayoussi, P. Zhu, D. Böcherer, A. Shakeel, and D. Helmer*, Controllable Wetting Transitions on Photoswitchable Physical Gels, ACS Appl. Mater. Interfaces, 2023,15, 27234-27242 | Link
F. Mayoussi, A. Usama, N. Nekoonam, I. Knauer, D. Böcherer, B. E. Rapp, D. Helmer, Influence of Parylene F Coatings on the Wetting Properties of Soft Polydimethylsiloxane (PDMS), Materials, 2023, 16(5), 1938 | Link
F. Mayoussi, A. Usama, K. Karimi, N. Nekoonam, A. Goralczyk, P. Zhu, D. Helmer, B. E. Rapp, Superrepellent Porous Polymer Surfaces by Replication from Wrinkled Polydimethylsiloxane/Parylene F, Materials, 2022, 15(22), 7903 | Link
, S. Savicheva, R. Montazeri, S. Fine , F. Mayoussi, , K. Steffen, , D. Helmer, B. E. , Spray-Coating of Superhydrophobic Coatings for Advanced Applications, Adv. Eng. Mater, 2022, 2201314 | Link
F. Mayoussi, Y. Chen, D. Mössner, S. Franco Corredor, A. Goralczyk, M. Mader, A. Warmbold, F. Kotz-Helmer, D. Helmer ,B. E. Rapp, Smooth Transparent Omniphobic Coatings with Remarkable Liquid Repellence, Adv. Mater. Interfaces, 2022, 2201080| Link
P. Pezeshkpour, K. Sachsenheimer, A. Goralczyk, F. Mayoussi, M. Mader, F. Kotz-Helmer, D. Helmer, B. E. Rapp, A Real-Time Capacitive Sensor to Detect the Stability of Salvinia Layers on Porous Superhydrophobic Polymers Under Shear, Adv. Mater. Technol., 2022, 2200287 | Link
A. Goralczyk, S. Bhagwat, F. Mayoussi, N. Nekoonam, K. Sachsenheimer, P. Hou, F. Kotz-Helmer, D. Helmer, B. E. Rapp, Application of Micro/Nanoporous Fluoropolymers with Reduced Bioadhesion in Digital Microfluidics, Nanomaterials, 2022, 12(13), 2201 | Link
S. Franco Corredor, F. Mayoussi, M. Luitz, A. Kick, A. Goralczyk, D. Böcherer, G. Vera, D. Helmer, F. Kotz-Helmer, B. E. Rapp, A Polystyrene Photoresin for Direct Lithography of Microfluidic Chips. Adv. Mater. Technol. 2022, 2200084 | Link
S. Bhagwat, C.O'Brien, A. Hamza, S. Sharma, C. Rein, M. Sanjaya, D. Helmer, F. Kotz-Helmer, P. Pezeshkpour, B.E.Rapp, An On-Chip Liquid Metal Plug Generator, Adv. Mater. 2022, 2201469 | Link
, M. Zhu, F. Mayoussi, M. Lallemang, M. Tschaikowsky, A. , S. Caliaro, F. Tauber, B. N. Balzer, F. , D. , B. E. , Study of repellence on polymeric surfaces with two individually adjustable pore hierarchies. Chem. Eng. J. 2022, 437, 135287 | Link
M. Mader, L. Hambitzer, P. Schlautmann, S. Jenne, C. Greiner, F. Hirth, D. Helmer, F. Kotz-Helmer, B.E. Rapp: "Melt-Extrusion-Based Additive Manufacturing of Transparent Fused Silica Glass", Adv. Sci., 2021, 8, 2103180 | Link
F. Mayoussi, E. H. Doeven, A. Kick, A. Goralczyk, Y. Thomann, P. Risch, R. M. Guijt, F. Kotz, D. Helmer, B. E. Rapp: "Facile fabrication of micro-/nanostructured, superhydrophobic membranes with adjustable porosity by 3D printing", Journal of Materials Chemistry A, 2021 | Link
, , , , , , , , , High Resolution Patterning of an Organic–Inorganic Photoresin for the Fabrication of Platinum Microstructures. Adv. Mater. 2021, 33, 2101992 | Link
V. Engemeann, I. Rink, M. F. Kilb, M. Hungsberg, D. Helmer, K. Schmitz: "Cell-based actin polymerization assay to analyze chemokine inhibitors", Journal of Pharmacological and Toxicological Methods, 2021 | Link
M. Mader, O. Schlatter, B. Heck, A. Warmbold, A. Dorn, H. Zappe, P. Risch, D. Helmer, F. Kotz, B. E. Rapp: “High-throughput injection molding of transparent fused silica glass”, Science, 2021 | Link
F. Kotz, A. S. Quick, P. Risch, T. Martin, T. Hoose, M. Thiel, D. Helmer, B. E. Rapp: “Two‐Photon Polymerization of Nanocomposites for the Fabrication of Transparent Fused Silica Glass Microstructures”, Advanced Materials, 33, 9, 2006341, 2021 | Link
F. Kotz, M. Mader, N. Dellen, P. Risch, A. Kick, D. Helmer, B. E. Rapp: “Fused deposition modeling of microfluidic chips in polymethylmethacrylate”, Micromachines, 11(9), 873, 2020. | Link
P. Risch, D. Helmer, F. Kotz, B. E. Rapp: "Analytical solution of the time-dependent microfluidic poiseuille flow in rectangular channel cross-sections and its numerical implementation in Microsoft Excel", Biosensors, 9(2), 67, 2019, |Link|
F. Kotz, P. Risch, K. Arnold, S. Sevim, J. Puigmarti-Luis, A. Quick, M. Thiel, A. Hrynevich, P. Dalton, D. Helmer, B. E. Rapp: “Fabrication of arbitrary three-dimensional suspended hollow microstructures in transparent fused silica glass”, Nature Communication, 10, 1439, 2019 | Link
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T. M. Nargang, R. Dierkes, J. Bruchmann, N. Keller, K. Sachsenheimer, C. Lee-Thedieck, F. Kotz, D. Helmer and B. E. Rapp: "Photolithographic structuring of soft, extremely foldable and autoclavable hydrophobic barriers in paper", Analytical Methods, 10, 4028-4035, 2018 | Link |
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F. Kotz, N. Schneider, A. Striegel, A. Wolfschläger, N. Keller, M. Worgull, W. Bauer, D. Schild, M. Milich, C. Greiner, D. Helmer, B. E. Rapp: “Glassomer: Processing Fused Silica Glass like a Polymer”, Advanced Materials, 30, 1707100, 2018 F. Kotz, P. Risch, D. Helmer, B. E. Rapp: “Highly Fluorinated Methacrylates for Optical 3D Printing of Microfluidic Devices”, Micromachines, 9, 3, 15, 2018 (invited) | Link
D. Helmer, N. Keller, F. Kotz, F. Stolz, C. Greiner, T. M. Nargang, K. Sachsenheimer, B. E. Rapp: „Transparent, abrasion-insensitive superhydrophobic coatings for real-world applications”, Nature Scientific Reports, 7, 1, 15078 | Link
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D. Helmer, A. Voigt, S. Wagner, N. Keller, K. Sachsenheimer, F. Kotz, T. M. Nargang, B. E. Rapp: "Suspended Liquid Subtractive Lithography: One-step generation of 3D channel geometries in viscous curable polymer matrices", Nature Scientific Reports 7, 7387, 2017 | Link
F. Kotz, K. Arnold, W. Bauer, D. Schild, N. Keller, K. Sachsenheimer, T. M. Nargang, C. Richter, D. Helmer, B. E. Rapp: "Three-dimensional Printing of Transparent Fused Silica Glass", Nature, 544, 337-339, 2017 | Link | Video | Media Coverage
C. Richter, F. Kotz, N. Keller, T. M. Nargang, K. Sachsenheimer, D. Helmer, B. E. Rapp: “An Analytical Solution to Neumann-Type Mixed Boundary Poiseuille Microfluidic Flow in Rectangular Channel Cross-Sections (Slip/No-Slip) Including a Numerical Technique to Derive It”, Journal of Biomedical Science and Engineering, 10, 205-219, 2017 | Link
C. Richter, K. Sachsenheimer, N. Keller, T. M. Nargang, D. Helmer, F. Kotz, B. E. Rapp: "An individual addressable and latchable actuator array for microfluidic systems", Microfluid Nanofluid 20:130, 2016. | Link
T. M. Nargang, M. Runck, D. Helmer, B. E. Rapp: "Functionalization of paper using photobleaching: a fast and convenient method for creating paper-based assays with colorimetric and fluorescent readout", Engineering in Life Sciences, 2016 | Link
C. Richter, F. Kotz, S. Giselbrecht, D. Helmer, B. E. Rapp: "Numerics made easy: solving the Navier–Stokes equation for arbitrary channel cross-sections using Microsoft Excel", Biomedical Microdevices 18:52, 2016 | Link
D. Helmer, K. Brahm, C. Helmer, J. S. Wack, G. Brenner-Weiss, K. Schmitz: "Two-channel image analysis method for the screening of OBOC libraries", Analytical Methods, 2016 | Link
N. Keller, T. M. Nargang, M. Runck, F. Kotz, A. Striegel, K. Sachsenheimer, D. Klemm, K. Länge, M. Worgull, C. Richter, D. Helmer, B. E. Rapp: "Tacky Cyclo Olefin Copolymer: A biocompatible bonding technique for the fabrication of microfluidic channels in COC", Lab Chip, 16, 1561-1564, 2016 | Link
F. Kotz, K. Plewa, W. Bauer, N. Schneider, N. Keller, T. Nargang, D. Helmer, K. Sachsenheimer, M. Schäfer, M. Worgull, C. Greiner, C. Richter, B. E. Rapp: “Liquid Glass: A Facile Soft Replication Method for Structuring Glass”, Advanced Materials, 28, 4646-4650, 2016 Media Coverage | Link
I. Rink, J. Rink, D. Helmer, D. Sachs, K. Schmitz: "A Haptotaxis Assay for Leukocytes Based on Surface-Bound Chemokine Gradients", Journal of Immunology, 2015 | Link
D. Helmer, I. Rink, J. A. R. Dalton, K. Brahm, M. Jöst, T. M. Nargang, W. Blum, P. Wadhwani, G. Brenner-Weiss, B. E. Rapp, J. Giraldo, K. Schmitz: “Rational design of a peptide capture agent for CXCL8 based on a model of the CXCL8:CXCR1 complex”, RSC Advances, 5, 25657-25668, 2015 | Link
T. M. Nargang, L. Brockmann, P. Nikolov, D. Schild, D. Helmer, N. Keller, K. Sachsenheimer, E. Wilhelm, L. Pires, M. Dirschka, A. Kolew, M. Worgull, S. Giselbrecht, C. Neumann, B. E. Rapp: “Liquid polystyrene: a room-temperature photocurable soft lithography compatible pour-and-cure-type polystyrene”, Lab Chip (special issue “Emerging Investigators"), 14, 2698-2708, 2014 | Link
Reviews
F. Kotz, P. Risch, D. Helmer, B. E. Rapp: “High-performance materials for 3D printing in chemical synthesis applications”, Advanced Materials (invited), 2019 |Link|
Books and Book chapters
F. Kotz, D. Helmer, B. E. Rapp: “3D Printing of Transparent Glasses”, book chapter within "3D Printing of Optical Components", 169-184, Springer, 2020 |Link
F. Kotz, D. Helmer, B. E. Rapp: “Emerging Technologies and Materials for High-Resolution 3D Printing of Microfluidic Chips”, book chapter within "Advances in Biochemical Engineering/Biotechnology", Springer Nature, 2020 |Link
D. Helmer, K. Schmitz: „Peptides and Peptide Analogs to Inhibit Protein-Protein Interactions“, Böldicke (ed.) Protein Targeting – Prediction, Selection and Activity of Specific Inhibitors, Springer, 2015 | Link
D. Helmer: “Synthesis and Test of Peptides and Peptoids for the Inhibition of Cytokines”, Cuvillier Verlag, Göttingen, 2015 | Link
Conference Contributions
K. Sachsenheimer, F. Mayoussi, A. Goralczyk, F. Kotz, D. Helmer and B. E. Rapp , Impedimetric Sensor for Salvinia Layer Detection on Fluoropor-coated Electrodes under Shear Stress, SPIE BiOS, 2021, Link
F. Mayoussi, E. H. Doeven, D. Helmer, B. E. Rapp, Membrane-based fluorinated microfluidic device for water-oil separation, SPIE BiOS, 2021
F. Kotz, P. Risch, M. Thiel, A. Quick, D. Helmer, B. E. Rapp: “Sacrificial Template Replication: Fabrication of arbitrary 3D microfluidic channels in transparent fused silica glass”, talk, SPIE Photonics West, San Francisco, USA, 2020
T. M. Nargang, R. Dierkes, J. Bruchmann, N. Keller, K. Sachsenheimer, F. Kotz, D. Helmer, B. E. Rapp: „Structuring unbreakable and autoclavable hydrophobic barriers in paper via direct printing and mask-based photolithography”, talk, SPIE Photonics West, San Francisco, 2019.
D. Helmer, F. Kotz, B. E. Rapp: „Suspended liquid subtractive lithography: printing three dimensional channels directly into uncured polymeric matrices”, talk, SPIE Photonics West, San Francisco, 2019.
P. Risch, F. Kotz, D. Helmer, B. E. Rapp: „3D printing of highly fluorinated methacrylates for the rapid prototyping of transparent and chemically-resistant microfluidic devices”, talk, SPIE Photonics West, San Francisco, 2019.
F. Kotz, A. Striegel, N. Schneider, M. Worgull, D. Helmer, B. E. Rapp: „High-throughput structuring of fused silica glass“; talk, MNE, Kopenhagen, 2018.
P. Risch, F. Kotz, D. Helmer, B. E. Rapp: "3D printing of highly fluorinated methacrylates for the fabrication of transparent and chemically resistant microfluidic devices", poster, 22nd International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), Kaohsiung, Taiwan, 2018.
P. Risch, F. Kotz, D. Helmer, B. E. Rapp: "3D printing of microfluidic glass reactors", poster, 22nd International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), Kaohsiung, Taiwan, 2018.
F. Kotz, A. Striegel, N. Schneider, P. Risch, M. Worgull, D. Helmer, B. E. Rapp: "High-throughput polymer molding of transparent fused silica microfluidic chips", poster, 22nd International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), Kaohsiung, Taiwan, 2018.
F. Kotz, P. Risch, K. Arnold, D. Helmer, B. E. Rapp: “Next generation 3D printing - The emergence of enabling materials”, talk, SPIE Defence and Security, Berlin, Germany, 2018| Link
D. Helmer: "Suspended Liquid Subtractive Lithography - Fabrication of three-dimensional microchannels by the immersion of "liquid threads"", talk, Microfluidics in the Upper Rhine Valley, IS2M Mulhouse 2018.
F. Kotz, D. Helmer, B. E. Rapp: "Additive manufacturing of microfluidic glass chips", talk, SPIE Photonics West, San Francisco, USA, 2018| Link
D. Helmer, A. Voigt, S. Wagner, N. Keller, K. Sachsenheimer, F. Kotz, T. M. Nargang, B. E. Rapp: "Additive manufacturing of microfluidic glass chips", talk, SPIE Photonics West, San Francisco, USA, 2018
D. Helmer, A. Voigt, B. E. Rapp: "Suspended Liquid Subtractive Lithography (SLSL) – 3D printing of microfluidic structures directly into PDMS", 21st International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), Savannah, USA, 2017
F. Kotz, D. Helmer, B. E. Rapp: "3D printing of microfluidic devices in highly fluorinated perfluoropolyethers (PFPE)", poster, 21st International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), Savannah, USA, 2017
T. M. Nargang, F. Kotz, N. Keller, D. Helmer, B. E. Rapp: “Rapid structuring of proteins on filter paper using lithography”, talk, SPIE Photonics West, San Francisco, USA, 2017| Link
D. Helmer, A. Voigt, S. Wagner, B. E. Rapp: "Rapid printing in PDMS – fused deposition modeling (FDM) meets microfluidics", talk, 20th International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), Dublin, Ireland, 2016
D. Helmer, N. Keller, B. E. Rapp: “Photolithographic structuring of highly fluorinated polymers for the fabrication of microfluidic chips”, talk, 19th International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), Gyeongju, Korea, 2015
T. M. Nargang, E. Wilhelm, F. Kotz, D. Helmer, B. E. Rapp: “UV-light based structuring of unbreakable hydrophobic barriers on commonly used papers”, poster, 19th International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), Gyeongju, Korea, 2015
D. Helmer, N. Keller, B. E. Rapp: “Reversibly Photoswitchable Hydrophilic/Hydrophobic Surfaces”, talk, ECOSS, Barcelona, Spain, 2015
F. Kotz, N. Keller, T.M. Nargang, K. Sachsenheimer, M. Dirschka, D. Helmer, C. Neumann, Bastian E. Rapp: “Computer aided microfluidics (CAMF): from 3D model to physical structures in less than a day”, talk, Euroanalysis, Bordeaux, France, 2015
T. M. Nargang, L. Brockmann, P. Nikolov, D. Schild, D. Helmer, N. Keller, M. Dirschka, A. Kolew, M. Worgull, S. Giselbrecht, C. Neumann, B. E. Rapp: “‘Liquid polystyrene’: a photocurable liquid polystyrene prepolymer as new material for microfluidic prototyping”, poster, 18th International Conference on Miniaturized Systems for Chemistry and Life Sciences (µTAS), San Antonio, USA, 2014
Patents
B. E. Rapp, D. Helmer, A. Voigt: "Verfahren und Vorrichtung zur Erzeugung einer dreidimensionalen Struktur in einer Matrix", DE102016219192, 2016 | Link.
B. E. Rapp, D. Helmer, A. Voigt: "Method and apparatus for generating a three-dimensional structure in a matrix“, EP3305495A1, 2016 | Link.
B. E. Rapp, D. Helmer, C. Richter, N. Keller: "Hochfluorierte nanostrukturierte Polymerschäume zur Herstellung superabweisender Oberflächen", DE102016012001A1, 2016 | Link.
B. E. Rapp, D. Helmer, C. Richter, N. Keller: “Highly fluorinated nanostructured polymer foams for producing super-repellent surface”, WO2018065094A1, 2016 | Link.
Miscellaneous
D. Helmer, B. E. Rapp: "Superabweisende Oberflächen - Die Entwicklung eines superhydrophoben Werkstoffs", GIT Labor-Fachzeitschrift, 2018 | Link
D. Helmer, B. E. Rapp: "Healthcare Material Platforms", HEALTH 2, Paneuropean Network, 2017. The NeptunLab is features on the cover page of the issue | Link | Cover