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Karlsruhe Institute of Technology

Young Investigator Network
YIN-Office

Engler-Bunte-Ring 21
76131 Karlsruhe

 

Tel. +49 721 608-46184

E-Mail: infoYpp5∂yin kit edu

 

Das KIT ist seit 2010 als familiengerechte Hochschule zertifiziert.
Felix Löffler

Dr. Felix Löffler

[sci.] Group leader at Max Planck Institute of Colloids and Interfaces
Physics
array technology

Group: [prev.] Carl Zeiss
Room: Germany, Potsdam


Current research

Which antibodies protect from infections? And which ones are useless or even harmful? If we would know, where antibodies have to bind to a pathogen to protect us, we could design a targeted vaccine or therapy with this knowledge.

Depending on the sequence of their 20 different amino acid building blocks, peptides (= small protein fragments) are a major class of antibody binders, which qualifies them to be used as diagnostic biomarkers or therapeutics. Therefore, a large set of different peptides has to be synthesized and screened in order to find e.g. novel biomarkers.

Our current research topics in microarray technology and application are:

  • Development of matrix-based array technology (Physics, Engineering, Chemistry)

  • Antibody profiling for infectious diseases (Biomedical research, Bioinformatics)

Application of microarrays

We employ novel high-density peptide arrays for the screening of patient sera. The principle is illustrated in Figure 1: The microarray slide with the immobilized molecule library (a) is incubated with a small amount of analyte (b). The fluorescently labeled analytic molecules bind to the surface, which is visible in the fluorescence image of the microarray (c).

Fig. 1. Principle of a patient serum analysis using a peptide array.

For a comprehensive serum readout regarding e.g. the malaria parasite Plasmodium falciparum, we translate the genomic information from databases into sequences of overlapping peptides (Fig. 2). These peptides are then synthesized on arrays and stained with patient sera.

Fig. 2. Generating a peptide array from overlapping proteome fragments of a pathogen.

Technology development

High-density peptide arrays represent an attractive method for high-throughput identification of peptide-protein interactions. They are essential to reduce the consumption of reagents required for the binding assay and, thus, save rare serum samples or expensive proteins. However, today's peptide array market is still dominated by the over 20 year old SPOT synthesis, which provides only low spot densities and achieves at most a few hundred spots per cm² if pre-synthesized peptides are spotted.

We developed a novel method of peptide array synthesis, which combines the high spot densities achieved by light-controlled lithographic methods with the cost-efficiency of one-cycle-per-layer coupling in biofunctional xerography.

Fig. 3. Selective combinatorial laser fusing for combinatorial peptide synthesis.

First, a homogenous layer of one particle type (with one kind of amino acid embedded within) is deposited onto a functionalized glass substrate. Subsequently, the layer is selectively irradiated with a laser beam (Fig. 3A), whereby the particles within the laser beam focus fuse together on the surface. Due to surface tension, the fused particle matrix forms a very small hemisphere, with its size being dependent only on the particle size and on the focus of the laser beam. Afterwards, unfused particles are simply blown away from the glass slide, whereas fused spots remain on the substrate due to much higher adhesion (Figure 3B). Repeating the patterning step with different particle types, results into a pattern of spots each comprising a freely chosen amino acid (Figure 3C).

Fig. 4. Coupling reaction of monomers after combinatorial laser fusing.

Although laser radiation heats and fuses the polymer matrix in order to form the distinct reaction hemispheres (Figure 4A), the laser pulse duration is too short to accomplish the coupling reaction. For an efficient diffusion and coupling of the amino acids to free amino groups on the surface, the complete layer of structured amino acid particles is heated to 90°C for several minutes (Figure 4B). At this temperature, the matrix material within the particles liquefies, and, thereby, serves as a solvent for peptide synthesis. Afterwards, the particle matrix and unreacted monomers are washed away (Figure 4C), and the transient protecting groups are removed to reveal free amino groups for the next synthesis layer (Figure 4D). Repeating this cycle for e.g. 13 consecutive layers results into an array of 13meric peptides.

Curriculum vitae

Young Investigator

Institute of Microstructure Technology, Karlsruhe Institute of Technology, Germany

Since 07/2014

Visting Scholar

UC Berkeley, USA

01/2014 – 06/2014

Postdoctoral fellow

Institute of Microstructure Technology, Karlsruhe Institute of Technology, Germany

10/2012 – 12/2013

Postdoctoral fellow

German Cancer Research Center Heidelberg, Germany

05/2012 – 10/2012

PhD

Kirchhoff Institute of Physics & German Cancer Research Center Heidelberg, Germany

10/2009 – 04/2012

Physics diploma and certificate in biophysics

Heidelberg University, Germany

10/2004 – 09/2009

Top publications

Journal covers
  • F. F. Loeffler, T. C. Foertsch, R. Popov, D. Althuon, M. Schlageter, M. Sedlmayr, B. Ridder, F.-X. Dang, C. v. Bojničić-Kninski, L. K. Weber, A. Fischer, J. Greifenstein, V. Bykovskaya, I. Buliev, F. R. Bischoff, L. Hahn, M. A. R. Meier, S. Bräse, A. K. Powell, T. S. Balaban, F. Breitling, A. Nesterov-Mueller. High-flexibility combinatorial peptide synthesis with laser-based transfer of monomers in solid matrix material. Nature Communications, 7:11844 (2016)
  • B. Muenster, A. Welle, B. Ridder, D. Althuon, J. Striffler, T. C. Foertsch, L. Hahn, R. Thelen, V. Stadler, A. Nesterov-Mueller, F. Breitling, F. F. Loeffler. Solid-material-based Coupling Efficiency Analyzed with Time-of-Flight Secondary Ion Mass Spectrometry. Applied Surface Science, 360:306–314 (2016)
  • F. Maerkle*, F. F. Loeffler* (* shared first author), S. Schillo, T. Foertsch, B. Muenster, J. Striffler, C. Schirwitz, F. R. Bischoff, F. Breitling, A. Nesterov-Mueller. High-Density Peptide Arrays with Combinatorial Laser Fusing. Advanced Materials, 26(22):3730–3734 (2014)
  • C. Schirwitz, F. F. Loeffler, T. Felgenhauer, V. Stadler, A. Nesterov-Müller, R. Dahint, F. Breitling, F. R. Bischoff. Purification of High-Complexity Peptide Microarrays by Spatially Resolved Array Transfer to Gold-Coated Membranes. Advanced Materials, 25(11):1598-1602 (2013)
  • F. Loeffler, C. Schirwitz, J. Wagner, K. Koenig, F. Maerkle, G. Torralba, M. Hausmann, F. R. Bischoff, A. Nesterov-Mueller, F. Breitling. Biomolecule arrays using functional combinatorial particle patterning on microchips. Advanced Functional Materials, 22(12):2503-2508 (2012)

List of publications

  1. J. Striffler, D. S. Mattes, S. Schillo, B. Muenster, A. Palermo, B. Ridder, A. Welle, V. Trouillet, V. Stadler, G. Markovic, G. Proll, S. Bräse, F. F. Loeffler, A. Nesterov-Mueller, F. Breitling. Replication of Polymer Based Peptide Microarrays by Multi Step Transfer. ChemNanoMat, in press (2016)
  2. F. F. Loeffler, T. C. Foertsch, R. Popov, D. Althuon, M. Schlageter, M. Sedlmayr, B. Ridder, F.-X. Dang, C. v. Bojničić-Kninski, L. K. Weber, A. Fischer, J. Greifenstein, V. Bykovskaya, I. Buliev, F. R. Bischoff, L. Hahn, M. A. R. Meier, S. Bräse, A. K. Powell, T. S. Balaban, F. Breitling, A. Nesterov-Mueller. High-flexibility combinatorial peptide synthesis with laser-based transfer of monomers in solid matrix material. Nature Communications, 7:11844 (2016)
  3. B. Muenster, A. Welle, B. Ridder, D. Althuon, J. Striffler, T. C. Foertsch, L. Hahn, R. Thelen, V. Stadler, A. Nesterov-Mueller, F. Breitling, F. F. Loeffler. Solid-material-based Coupling Efficiency Analyzed with Time-of-Flight Secondary Ion Mass Spectrometry. Applied Surface Science, 360:306–314 (2016)
  4. F. F. Loeffler (shared corresponding author), J. Pfeil, K. Heiss. High-density peptide arrays for malaria vaccine development. Methods in Molecular Biology, Vaccine Design, Methods and Protocols: Volume 1: Vaccines for Human Diseases, Humana Press (2016)
  5. L.K. Weber, A. Fischer, T. Schorb, M. Soehindrijo, T.C. Förtsch,  C. v. Bojnicic-Kninski, D. Althuon, F. F. Loeffler, F. Breitling, J. Hubbuch, A. Nesterov-Müller. Automated Microfluidic System with Optical Setup for the Investigation of Peptide-Antibody Interactions in an Array Format. Microsystems Technology in Germany 2016. (2016)
  6. A. Nesterov-Mueller, F. Märkle,  L. Hahn, T. Förtsch, S. Schillo, V. Bykovskaya, M. Sedlmayr, L.K. Weber, B. Ridder, M. Soehindrijo, B. Münster, J. Striffler, F. R. Bischoff, F. Breitling, F. F. Loeffler. Particle-based microarrays of oligonucleotides and oligopeptides. MDPI Microarrays, New and Old Technologies for Generation of Microarrays, 3(4):245-262 (2014)
  7. F. Maerkle*, F. F. Loeffler* (shared first author), S. Schillo, T. Foertsch, B. Muenster, J. Striffler, C. Schirwitz, F. R. Bischoff, F. Breitling, A. Nesterov-Mueller. High-Density Peptide Arrays with Combinatorial Laser Fusing. Advanced Materials, 26(22):3730–3734 (2014)
  8. F. F. Loeffler (shared corresponding author), Y.-C. Cheng, B. Muenster, J. Striffler, F. C. Liu, F. R. Bischoff, E. Doersam, F. Breitling, A. Nesterov-Mueller.  Printing Peptide Arrays with a Complementary Metal Oxide Semiconductor Chip. Fundamentals and application of new bioproduction systems, Advances in Biochemical Engineering/Biotechnology, (2013)
  9. C. Schirwitz, F. F. Loeffler, T. Felgenhauer, V. Stadler, A. Nesterov-Müller, R. Dahint, F. Breitling, F. R. Bischoff. Purification of High-Complexity Peptide Microarrays by Spatially Resolved Array Transfer to Gold-Coated Membranes. Advanced Materials, 25(11):1598-1602 (2013)
  10. C. Schirwitz, F. F. Loeffler (corresponding author), T. Felgenhauer, V. Stadler, F. Breitling, F. R. Bischoff. Sensing Immune Responses with Customized Peptide Microarrays. Biointerphases, 7:47 (2012)
  11. F. Loeffler, C. Schirwitz, J. Wagner, K. Koenig, F. Maerkle, G. Torralba, M. Hausmann, F. R. Bischoff, A. Nesterov-Mueller, F. Breitling. Biomolecule arrays using functional combinatorial particle patterning on microchips. Advanced Functional Materials, 22(12):2503-2508 (2012)
  12. J. Wagner, F. Löffler, T. Förtsch, C. Schirwitz, S. Fernandez, H. Hinkers, H. F. Arlinghaus, F. Painke, K. Koenig, F. R. Bischoff, A. Nesterov-Müller, F. Breitling, M. Hausmann, V. Lindenstruth. Image Processing Quality Analysis for Particle Based Peptide Array Production on a Microchip, in Advanced Image Acquisition, Processing Techniques and Applications I, Dimitrios Ventzas (Ed.), ISBN: 978-953-51-0342-4, InTech, (2012)
  13. F. Loffler, Y.-C. Cheng, T. Fortsch, E. Dorsam, R. Bischoff, F. Breitling, A. Nesterov-Muller. Biofunctional Xerography, in Biotechnology of Biopolymers, Magdy Elnashar (Ed.), ISBN: 978-953-307-179-4, InTech, (2011)
  14. J. Wagner, K. Koenig, T. Foertsch, F. Loeffler, S. Fernandez, T. Felgenhauer, F. Painke, G. Torralba, V. Lindenstruth, V. Stadler, F.R. Bischoff, F. Breitling, M. Hausmann, A. Nesterov-Mueller. Microparticle transfer onto pixel electrodes of 45 µm pitch on HV-CMOS chips – Simulation and experiment. Sensors and Actuators A: Physical, 172(2):533-545 (2011)
  15. F. Löffler, J. Wagner, K. König, F. Märkle, S. Fernandez, C. Schirwitz, G. Torralba, M. Hausmann, V. Lindenstruth, F. R. Bischoff, F. Breitling, A. Nesterov. High-precision combinatorial deposition of micro particle patterns on a microelectronic chip. Journal of Aerosol Science and Technology 45(1):65-74 (2011)
  16. F. Breitling, F. Löffler, C. Schirwitz, Y.C. Cheng, F. Märkle, K. König, T. Felgenhauer, E Dörsam, F.R. Bischoff, A. Nesterov-Müller. Alternative Setups for Automated Peptide Synthesis. Mini-Reviews in Organic Chemistry, 8:121-131 (2011)
  17. J. Wagner,  F. Löffler,  K. König,  S. Fernandez, A. Nesterov-Müller, F. Breitling, F. R. Bischoff, V. Stadler, M. Hausmann, V. Lindenstruth. Quality analysis of selective microparticle deposition on electrically programmable surfaces. Review of Scientific Instruments 81(7):073703 (2010)
  18. K. König, I. Block, A. Nesterov, G. Torralba, S. Fernandez, T. Felgenhauer, K. Leibe, C. Schirwitz, F. Löffler, F. Painke, J. Wagner, U. Trunk, F.R. Bischoff, F. Breitling, V. Stadler, M. Hausmann, V. Lindenstruth. Programmable high voltage CMOS chips for particle-based high-density combinatorial peptide synthesis. Sensors and Actuators B: Chemical 147(2):418-427 (2010)
  19. A. Nesterov, F. Löffler, Y.-C. Cheng, G. Torralba, K. König, M. Hausmann, V. Lindenstruth, V. Stadler, F. R. Bischoff, F. Breitling. Characterization of triboelectrically charged particles deposited on dielectric surfaces, Journal of Physics D: Applied Physics, 43(16):165301 (2010)
  20. A. Nesterov, E. Dörsam, Y.C. Cheng, C. Schirwitz, F. Märkle, F. Löffler, K. König, V. Stadler, R. Bischoff, F. Breitling. Peptide Arrays with a Chip. Methods in Molecular Biology, Small Molecule Microarrays, Vol. 669, Humana Press, (2010)
  21. Y.C. Cheng, F. Löffler, K. König, A. Nesterov, E. Dörsam, F. Breitling. Chip Printer. Proceedings of the 2nd WSEAS International Conference on Nanotechnology. ISSN: 1790-5117, 19-22. (2010)
  22. A. Nesterov, F. Löffler, M. Hausmann, V. Stadler, F.R. Bischoff, F. Breitling.
    Manipulation of solid particle aerosols for combinatorial fabrication of molecular libraries. SPIE Proceedings, ILLA'09, ISSN: 1314-068X, Smolyan, October 18-22, 2009, 332-341 (2009)
  23. A. Nesterov, F. Löffler, K. König, U. Trunk, K. Leibe, T. Felgenhauer, F.R. Bischoff, F. Breitling, V. Lindenstruth, V. Stadler, M. Hausmann. Measurement of triboelectric charging of moving micro particles by means of an inductive cylindrical probe. Journal of Physics D: Applied Physics, 40(19):6115–6120 (2007)
  24. A. Nesterov, F. Löffler, K. König, U. Trunk, K. Leibe, T. Felgenhauer, V. Stadler, F.R. Bischoff, F. Breitling, V. Lindenstruth, M. Hausmann. Noncontact charge measurement of moving microparticles contacting dielectric surfaces. Review of Scientific Instruments, 78(7):075111 (2007)