Andreas Herrmann

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Organization: University of Groningen , Belgium
Department: Department of Polymer Chemistry
Title: (PhD)

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Co-reporter:Kai Liu, Chao Ma, Robert Göstl, Lei Zhang, and Andreas Herrmann
Accounts of Chemical Research May 16, 2017 Volume 50(Issue 5) pp:1212-1212
Publication Date(Web):May 5, 2017
DOI:10.1021/acs.accounts.7b00030
ConspectusBiomacromolecules, such as nucleic acids, proteins, and virus particles, are persistent molecular entities with dimensions that exceed the range of their intermolecular forces hence undergoing degradation by thermally induced bond-scission upon heating. Consequently, for this type of molecule, the absence of a liquid phase can be regarded as a general phenomenon. However, certain advantageous properties usually associated with the liquid state of matter, such as processability, flowability, or molecular mobility, are highly sought-after features for biomacromolecules in a solvent-free environment. Here, we provide an overview over the design principles and synthetic pathways to obtain solvent-free liquids of biomacromolecular architectures approaching the topic from our own perspective of research. We will highlight the milestones in synthesis, including a recently developed general surfactant complexation method applicable to a large variety of biomacromolecules as well as other synthetic principles granting access to electrostatically complexed proteins and DNA.These synthetic pathways retain the function and structure of the biomacromolecules even under extreme, nonphysiological conditions at high temperatures in water-free melts challenging the existing paradigm on the role of hydration in structural biology. Under these conditions, the resulting complexes reveal their true potential for previously unthinkable applications. Moreover, these protocols open a pathway toward the assembly of anisotropic architectures, enabling the formation of solvent-free biomacromolecular thermotropic liquid crystals. These ordered biomaterials exhibit vastly different mechanical properties when compared to the individual building blocks. Beyond the preparative aspects, we will shine light on the unique potential applications and technologies resulting from solvent-free biomacromolecular fluids: From charge transport in dehydrated liquids to DNA electrochromism to biocatalysis in the absence of a protein hydration shell. Moreover, solvent-free biological liquids containing viruses can be used as novel storage and process media serving as a formulation technology for the delivery of highly concentrated bioactive compounds. We are confident that this new class of hybrid biomaterials will fuel further studies and applications of biomacromolecules beyond water and other solvents and in a much broader context than just the traditional physiological conditions.
Co-reporter:Pavlo Gordiichuk;Diego Pesce;Olga E. Castañeda Ocampo;Alessio Marcozzi;Gert-Jan A. H. Wetzelaer;Avishek Paul;Mark Loznik;Ekaterina Gloukhikh;Shachar Richter;Ryan C. Chiechi
Advanced Science 2017 Volume 4(Issue 5) pp:
Publication Date(Web):2017/05/01
DOI:10.1002/advs.201600393
Interfacing proteins with electrode surfaces is important for the field of bioelectronics. Here, a general concept based on phage display is presented to evolve small peptide binders for immobilizing and orienting large protein complexes on semiconducting substrates. Employing this method, photosystem I is incorporated into solid-state biophotovoltaic cells.
Co-reporter:Jinsong Han, Chao Ma, Benhua Wang, Markus Bender, ... Uwe H.F. Bunz
Chem 2017 Volume 2, Issue 6(Volume 2, Issue 6) pp:
Publication Date(Web):8 June 2017
DOI:10.1016/j.chempr.2017.04.008
•Two hypothesis-free sensor arrays discriminate whiskies on the basis of fluorescence modulation•The arrays recognize brand, origin, blending state, age, and taste of the tested whiskies•Non-specific interactions, such as hydrophobics and electrostatics, are operativeThe simple discrimination of complex analytes (beverages, foodstuffs, prescription drugs, etc.) is important for economic and health-related reasons. Because one cannot construct specific sensors or assays for analytes such as whiskies, powerful alternative methods are needed. Two hypothesis-free three-element arrays of charged fluorescent dyes (one composed of fluorescent proteins and the other composed of large π systems) differentiate more than 30 whiskies according to their differential fluorescence intensity modulation along the axes of age, area of origin, and taste. Small, arbitrarily selected arrays display a fundamentally important and unexpected power of discrimination for very different analytes, which we will harness in the future to discriminate counterfeit consumer goods (e.g., perfumes and alcoholic beverages) and prescription drugs (outdated, adulterated, counterfeit, brand free, etc.). Such an extension has a direct significant impact on society and some impact on the economy.In biology, non-specific interactions are ubiquitous and important, whereas in chemistry, non-specificity or non-selectivity is suspect. We present simple tongues consisting of fluorescent polyelectrolytes or chimeric green fluorescent proteins (GFPs) to discriminating 33 different whiskies according to their country of origin (Ireland, US, or Scotland), brand, blend status (blend or single malt), age, and taste (rich or light). The mechanism of action for these tongues is differential quenching of the fluorescence of the poly(aryleneethynylene)s or the GFPs by the complex mixture of colorants (vanillin, vanillic acid, oak lactones, tannins, etc.; the interactome) extracted from the oak barrels and added caramel coloring. The differential binding and signal generation of the interactomes to the polymers and proteins result from hydrophobic and electrostatic interactions. The collected quenching data, i.e., the response patterns, were analyzed by linear discriminant analysis. Our tongues do not need any sample preparation and are equal or superior to state-of-the-art mass spectrometric methods with respect to speed, resolution, and efficiency of discrimination.Download high-res image (263KB)Download full-size image
Co-reporter:Kai Liu;Lifei Zheng;Chao Ma;Robert Göstl
Chemical Society Reviews 2017 vol. 46(Issue 16) pp:5147-5172
Publication Date(Web):2017/08/14
DOI:10.1039/C7CS00165G
Over the last few years, DNA–surfactant complexes have gained traction as unique and powerful materials for potential applications ranging from optoelectronics to biomedicine because they self-assemble with outstanding flexibility spanning packing modes from ordered lamellar, hexagonal and cubic structures to disordered isotropic phases. These materials consist of a DNA backbone from which the surfactants protrude as non-covalently bound side chains. Their formation is electrostatically driven and they form bulk films, lyotropic as well as thermotropic liquid crystals and hydrogels. This structural versatility and their easy-to-tune properties render them ideal candidates for assembly in bulk films, for example granting directional conductivity along the DNA backbone, for dye dispersion minimizing fluorescence quenching allowing applications in lasing and nonlinear optics or as electron blocking and hole transporting layers, such as in LEDs or photovoltaic cells, owing to their extraordinary dielectric properties. However, they do not only act as host materials but also function as a chromophore itself. They can be employed within electrochromic DNA–surfactant liquid crystal displays exhibiting remarkable absorptivity in the visible range whose volatility can be controlled by the external temperature. Concomitantly, applications in the biological field based on DNA–surfactant bulk films, liquid crystals and hydrogels are rendered possible by their excellent gene and drug delivery capabilities. Beyond the mere exploitation of their material properties, DNA–surfactant complexes proved outstandingly useful for synthetic chemistry purposes when employed as scaffolds for DNA-templated reactions, nucleic acid modifications or polymerizations. These promising examples are by far not exhaustive but foreshadow their potential applications in yet unexplored fields. Here, we will give an insight into the peculiarities and perspectives of each material and are confident to inspire future developments and applications employing this emerging substance class.
Co-reporter:Lei Zhang;Lifei Zheng;Zhuojun Meng;Konstantin Balinin;Mark Loznik
Chemical Communications 2017 vol. 53(Issue 47) pp:6331-6334
Publication Date(Web):2017/06/08
DOI:10.1039/C7CC02500A
The speed-up of covalent bond formation was achieved between a sulfhydryl group and a 2-bromopropionic acid derivative by utilizing sliding peptide-modified substrates. Moreover, a new type of DNA cleaving reagent was developed, consisting of pVIc covalently coupled to verteporfin. This peptide–porphyrin conjugate allowed targeting of DNA and resulted in increased photodegradation of double-stranded nucleic acids.
Co-reporter:Huige Yang;Chao Ma;Kaiyong Li;Kai Liu;Mark Loznik;Rosalie Teeuwen;Jan C. M. van Hest;Xin Zhou;Jianjun Wang
Advanced Materials 2016 Volume 28( Issue 25) pp:5008-5012
Publication Date(Web):
DOI:10.1002/adma.201600496
Co-reporter:Alexander Turkin, Lei Zhang, Alessio Marcozzi, Walter F. Mangel, Andreas Herrmann and Antoine M. van Oijen  
Chemical Science 2016 vol. 7(Issue 2) pp:916-920
Publication Date(Web):07 Oct 2015
DOI:10.1039/C5SC03063C
Numerous biological processes involve association of a protein with its binding partner, an event that is preceded by a diffusion-mediated search bringing the two partners together. Often hindered by crowding in biologically relevant environments, three-dimensional diffusion can be slow and result in long bimolecular association times. Similarly, the initial association step between two binding partners often represents a rate-limiting step in biotechnologically relevant reactions. We demonstrate the practical use of an 11-a.a. DNA-interacting peptide derived from adenovirus to reduce the dimensionality of diffusional search processes and speed up associations between biological macromolecules. We functionalize binding partners with the peptide and demonstrate that the ability of the peptide to one-dimensionally diffuse along DNA results in a 20-fold reduction in reaction time. We also show that modifying PCR primers with the peptide sled enables significant acceleration of standard PCR reactions.
Co-reporter:Pavlo I. Gordiichuk, Dolev Rimmerman, Avishek Paul, Daniel A. Gautier, Agnieszka Gruszka, Manfred Saller, Jan Willem de Vries, Gert-Jan A. H. Wetzelaer, Marianna Manca, Widianta Gomulya, Maayan Matmor, Ekaterina Gloukhikh, Mark Loznik, Nurit Ashkenasy, Paul W. M. Blom, Matthias Rögner, Maria Antonietta Loi, Shachar Richter, and Andreas Herrmann
Bioconjugate Chemistry 2016 Volume 27(Issue 1) pp:36
Publication Date(Web):November 30, 2015
DOI:10.1021/acs.bioconjchem.5b00583
Photosynthesis is Nature’s major process for converting solar into chemical energy. One of the key players in this process is the multiprotein complex photosystem I (PSI) that through absorption of incident photons enables electron transfer, which makes this protein attractive for applications in bioinspired photoactive hybrid materials. However, the efficiency of PSI is still limited by its poor absorption in the green part of the solar spectrum. Inspired by the existence of natural phycobilisome light-harvesting antennae, we have widened the absorption spectrum of PSI by covalent attachment of synthetic dyes to the protein backbone. Steady-state and time-resolved photoluminescence reveal that energy transfer occurs from these dyes to PSI. It is shown by oxygen-consumption measurements that subsequent charge generation is substantially enhanced under broad and narrow band excitation. Ultimately, surface photovoltage (SPV) experiments prove the enhanced activity of dye-modified PSI even in the solid state.
Co-reporter:Kai Liu;Diego Pesce;Chao Ma;Michael Tuchb;Min Shuai;Dong Chen;Juanjuan Su;Qing Liu;Jennifer Y. Gerasimov;Anke Kolbe;Wojciech Zajaczkowski;Wojciech Pisula;Klaus Müllen;Noel A. Clark
Advanced Materials 2015 Volume 27( Issue 15) pp:2459-2465
Publication Date(Web):
DOI:10.1002/adma.201405182
Co-reporter:Olga E. Castañeda Ocampo; Pavlo Gordiichuk; Stefano Catarci; Daniel A. Gautier; Andreas Herrmann;Ryan C. Chiechi
Journal of the American Chemical Society 2015 Volume 137(Issue 26) pp:8419-8427
Publication Date(Web):June 9, 2015
DOI:10.1021/jacs.5b01241
Recently, photoactive proteins have gained a lot of attention due to their incorporation into bioinspired (photo)electrochemical and solar cells. This paper describes the measurement of the asymmetry of current transport of self-assembled monolayers (SAMs) of the entire photosystem I (PSI) protein complex (not the isolated reaction center, RCI), on two different “director SAMs” supported by ultraflat Au substrates. The director SAMs induce the preferential orientation of PSI, which manifest as asymmetry in tunneling charge-transport. We measured the oriented SAMs of PSI using eutectic Ga–In (EGaIn), a large-area technique, and conducting probe atomic force microscopy (CP-AFM), a single-complex technique, and determined that the transport properties are comparable. By varying the temperatures at which the measurements were performed, we found that there is no measurable dependence of the current on temperature from ±0.1 to ±1.0 V bias, and thus, we suggest tunneling as the mechanism for transport; there are no thermally activated (e.g., hopping) processes. Therefore, it is likely that relaxation in the electron transport chain is not responsible for the asymmetry in the conductance of SAMs of PSI complexes in these junctions, which we ascribe instead to the presence of a large, net dipole moment present in PSI.
Co-reporter:Wei Chen; Jennifer Y. Gerasimov; Pei Zhao; Kai Liu
Journal of the American Chemical Society 2015 Volume 137(Issue 40) pp:12884-12889
Publication Date(Web):September 24, 2015
DOI:10.1021/jacs.5b05432
Preserving DNA hybridization in organic solvents could someday serve to significantly extend the applicability of DNA-based technologies. Here, we present a method that can be used to solubilize double-stranded DNA at high concentrations in organic media. This method requires first precipitating a DNA molecule from the aqueous environment with an anilinium derivative and subsequently exchanging this moiety with an amine-containing surfactant in organic solvent. We demonstrate that this method yields complete exchange of the surfactant and allows for the modification of DNA with hydrophobic primary, secondary, and tertiary alkylamines and ordered functional π-systems. Using this approach, we fabricate a multichromophoric light harvesting system that would be unattainable by traditional methods. Additionally, this method makes it possible to use small, hydrophilic molecules to solubilize DNA in organic solvents, which reduces the shielding around the DNA and makes the macromolecule more accessible for further chemical modification. We believe that this approach will prove tremendously beneficial in expanding the scope of DNA-based nano- and biotechnologies.
Co-reporter:Jun Yue;Pei Zhao;Jennifer Y. Gerasimov;Marieke van de Lagemaat;Arjen Grotenhuis;Minie Rustema-Abbing;Henny C. van der Mei;Henk J. Busscher;Yijin Ren
Advanced Functional Materials 2015 Volume 25( Issue 43) pp:6756-6767
Publication Date(Web):
DOI:10.1002/adfm.201502384

3D printing is seen as a game-changing manufacturing process in many domains, including general medicine and dentistry, but the integration of more complex functions into 3D-printed materials remains lacking. Here, it is expanded on the repertoire of 3D-printable materials to include antimicrobial polymer resins, which are essential for development of medical devices due to the high incidence of biomaterial-associated infections. Monomers containing antimicrobial, positively charged quaternary ammonium groups with an appended alkyl chain are either directly copolymerized with conventional diurethanedimethacrylate/glycerol dimethacrylate (UDMA/GDMA) resin components by photocuring or prepolymerized as a linear chain for incorporation into a semi-interpenetrating polymer network by light-induced polymerization. For both strategies, dental 3D-printed objects fabricated by a stereolithography process kill bacteria on contact when positively charged quaternary ammonium groups are incorporated into the photocurable UDMA/GDMA resins. Leaching of quaternary ammonium monomers copolymerized with UDMA/GDMA resins is limited and without biological consequences within 4–6 d, while biological consequences could be confined to 1 d when prepolymerized quaternary ammonium group containing chains are incorporated in a semi-interpenetrating polymer network. Routine clinical handling and mechanical properties of the pristine polymer matrix are maintained upon incorporation of quaternary ammonium groups, qualifying the antimicrobially functionalized, 3D-printable composite resins for clinical use.

Co-reporter:Kai Liu;Dr. Min Shuai;Dr. Dong Chen;Michael Tuchb;Dr. Jennifer Y. Gerasimov;Juanjuan Su;Qing Liu;Wojciech Zajaczkowski;Dr. Wojciech Pisula;Dr. Klaus Müllen; Noel A. Clark;Dr. Andreas Herrmann
Chemistry - A European Journal 2015 Volume 21( Issue 13) pp:4898-4903
Publication Date(Web):
DOI:10.1002/chem.201500159

Abstract

As DNA exhibits persistent structures with dimensions that exceed the range of their intermolecular forces, solid-state DNA undergoes thermal degradation at elevated temperatures. Therefore, the realization of solvent-free DNA fluids, including liquid crystals and liquids, still remains a significant challenge. To address this intriguing issue, we demonstrate that combining DNA with suitable cationic surfactants, followed by dehydration, can be a simple generic scheme for producing these solvent-free DNA fluid systems. In the anhydrous smectic liquid crystalline phase, DNA sublayers are intercalated between aliphatic hydrocarbon sublayers. The lengths of the DNA and surfactant are found to be extremely important in tuning the physical properties of the fluids. Stable liquid-crystalline and liquid phases are obtained in the −20 °C to 200 °C temperature range without thermal degradation of the DNA. Thus, a new type of DNA-based soft biomaterial has been achieved, which will promote the study and application of DNA in a much broader context.

Co-reporter:Kai Liu;Dr. Min Shuai;Dr. Dong Chen;Michael Tuchb;Dr. Jennifer Y. Gerasimov;Juanjuan Su;Qing Liu;Wojciech Zajaczkowski;Dr. Wojciech Pisula;Dr. Klaus Müllen; Noel A. Clark;Dr. Andreas Herrmann
Chemistry - A European Journal 2015 Volume 21( Issue 13) pp:
Publication Date(Web):
DOI:10.1002/chem.201581361
Co-reporter:Pavlo I. Gordiichuk;Gert-Jan A. H. Wetzelaer;Dolev Rimmerman;Agnieszka Gruszka;Jan Willem de Vries;Manfred Saller;Daniel A. Gautier;Stefano Catarci;Diego Pesce;Shachar Richter;Paul W. M. Blom
Advanced Materials 2014 Volume 26( Issue 28) pp:4863-4869
Publication Date(Web):
DOI:10.1002/adma.201401135
Co-reporter:Kai Liu ; Lifei Zheng ; Qing Liu ; Jan Willem de Vries ; Jennifer Y. Gerasimov
Journal of the American Chemical Society 2014 Volume 136(Issue 40) pp:14255-14262
Publication Date(Web):September 29, 2014
DOI:10.1021/ja5080486
DNA-incorporating hydrophobic moieties can be synthesized by either solid-phase or solution-phase coupling. On a solid support the DNA is protected, and hydrophobic units are usually attached employing phosphoramidite chemistry involving a DNA synthesizer. On the other hand, solution coupling in aqueous medium results in low yields due to the solvent incompatibility of DNA and hydrophobic compounds. Hence, the development of a general coupling method for producing amphiphilic DNA conjugates with high yield in solution remains a major challenge. Here, we report an organic-phase coupling strategy for nucleic acid modification and polymerization by introducing a hydrophobic DNA–surfactant complex as a reactive scaffold. A remarkable range of amphiphile–DNA structures (DNA–pyrene, DNA–triphenylphosphine, DNA–hydrocarbon, and DNA block copolymers) and a series of new brush-type DNA side-chain homopolymers with high DNA grafting density are produced efficiently. We believe that this method is an important breakthrough in developing a generalized approach to synthesizing functional DNA molecules for self-assembly and related technological applications.
Co-reporter:Netta Hendler;Jurjen Wildeman;Elad. D. Mentovich;Tobias Schnitzler;Bogdan Belgorodsky;Deepak K. Prusty;Dolev Rimmerman;Shachar Richter
Macromolecular Bioscience 2014 Volume 14( Issue 3) pp:320-326
Publication Date(Web):
DOI:10.1002/mabi.201300329

Abstract

Optically active bio-composite blends of conjugated polymers or oligomers are fabricated by complexing them with bovine submaxilliary mucin (BSM) protein. The BSM matrix is exploited to host hydrophobic extended conjugated π-systems and to prevent undesirable aggregation and render such materials water soluble. This method allows tuning the emission color of solutions and films from the basic colors to the technologically challenging white emission. Furthermore, electrically driven light emitting biological devices are prepared and operated.

Co-reporter:Lifei Zheng;Dong Chen;Alessio Marcozzi;Kai Liu;Juanjuan Su;Anke Kolbe;Diego Pesce;Wojciech Pisula;Klaus Müllen;Wojciech Zajaczkowski;Noel A. Clark
PNAS 2014 Volume 111 (Issue 52 ) pp:18596-18600
Publication Date(Web):2014-12-30
DOI:10.1073/pnas.1421257111
Complexation of biomacromolecules (e.g., nucleic acids, proteins, or viruses) with surfactants containing flexible alkyl tails, followed by dehydration, is shown to be a simple generic method for the production of thermotropic liquid crystals. The anhydrous smectic phases that result exhibit biomacromolecular sublayers intercalated between aliphatic hydrocarbon sublayers at or near room temperature. Both this and low transition temperatures to other phases enable the study and application of thermotropic liquid crystal phase behavior without thermal degradation of the biomolecular components.
Co-reporter:Dr. Andreas A. Bastian;Dr. Alberto Rodríguez-Pulido;Agnieszka Gruszka;Dr. Jennifer Y. Gerasimov ; Andreas Herrmann
Chemistry – An Asian Journal 2014 Volume 9( Issue 8) pp:2225-2231
Publication Date(Web):
DOI:10.1002/asia.201402327

Abstract

Site-specific derivatization of chemically equivalent functional groups has recently been facilitated by the introduction of high-affinity aptamers as non-covalent protective groups. More specifically, a series of RNA aptamers have proven to be highly efficient in enhancing the regioselectivity of reactions with the aminoglycoside antibiotic neomycin B, which carries several chemically indistinguishable amino and hydroxy groups. Since small-molecule targets tend to exhibit multiple modes of binding with a single aptamer, the impact of secondary binding sites on the regioselectivity should be considered. To address this issue, we investigated a series of well-characterized RNA aptamers that bind neomycin B and propose a mechanism that accounts for the regioselective outcome of these transformations. We further demonstrate that the regioselectivity induced by non-covalent aptamer protective groups is determined by the number of binding sites, their affinity, and the mode of interaction with the guest molecule.

Co-reporter:Lifei Zheng;Alessio Marcozzi;Dr. Jennifer Y. Gerasimov ;Dr. Andreas Herrmann
Angewandte Chemie International Edition 2014 Volume 53( Issue 29) pp:7599-7603
Publication Date(Web):
DOI:10.1002/anie.201403829

Abstract

Cyclic peptides containing a disulfide bridge were identified as a simple and versatile coordination sphere for asymmetric catalysis. Upon complexation with Cu2+ ions they catalyze Diels–Alder and Friedel–Crafts reactions with high enantioselectivities of up to 99 % ee and 86 % ee, respectively. Moreover, the peptides ligands were systematically optimized with the assistance of “Alanine Scanning”. This biomolecular design could greatly expand the choice of peptide scaffolds for artificial metallopeptide catalysts.

Co-reporter:Agnieszka K. Muszanska, Edward T. J. Rochford, Agnieszka Gruszka, Andreas A. Bastian, Henk J. Busscher, Willem Norde, Henny C. van der Mei, and Andreas Herrmann
Biomacromolecules 2014 Volume 15(Issue 6) pp:
Publication Date(Web):April 29, 2014
DOI:10.1021/bm500168s
This paper describes the synthesis and characterization of polymer–peptide conjugates to be used as infection-resistant coating for biomaterial implants and devices. Antiadhesive polymer brushes composed of block copolymer Pluronic F-127 (PF127) were functionalized with antimicrobial peptides (AMP), able to kill bacteria on contact, and arginine–glycine–aspartate (RGD) peptides to promote the adhesion and spreading of host tissue cells. The antiadhesive and antibacterial properties of the coating were investigated with three bacterial strains: Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa. The ability of the coating to support mammalian cell growth was determined using human fibroblast cells. Coatings composed of the appropriate ratio of the functional components: PF127, PF127 modified with AMP, and PF127 modified with RGD showed good antiadhesive and bactericidal properties without hampering tissue compatibility.
Co-reporter:Lifei Zheng;Alessio Marcozzi;Dr. Jennifer Y. Gerasimov ;Dr. Andreas Herrmann
Angewandte Chemie 2014 Volume 126( Issue 29) pp:7729-7733
Publication Date(Web):
DOI:10.1002/ange.201403829

Abstract

Cyclic peptides containing a disulfide bridge were identified as a simple and versatile coordination sphere for asymmetric catalysis. Upon complexation with Cu2+ ions they catalyze Diels–Alder and Friedel–Crafts reactions with high enantioselectivities of up to 99 % ee and 86 % ee, respectively. Moreover, the peptides ligands were systematically optimized with the assistance of “Alanine Scanning”. This biomolecular design could greatly expand the choice of peptide scaffolds for artificial metallopeptide catalysts.

Co-reporter:Dr. Alberto Rodríguez-Pulido;Alina I. Kondrachuk;Dr. Deepak K. Prusty;Jia Gao;Dr. Maria A. Loi;Dr. Andreas Herrmann
Angewandte Chemie 2013 Volume 125( Issue 3) pp:1042-1046
Publication Date(Web):
DOI:10.1002/ange.201206783
Co-reporter:Dr. Alberto Rodríguez-Pulido;Alina I. Kondrachuk;Dr. Deepak K. Prusty;Jia Gao;Dr. Maria A. Loi;Dr. Andreas Herrmann
Angewandte Chemie International Edition 2013 Volume 52( Issue 3) pp:1008-1012
Publication Date(Web):
DOI:10.1002/anie.201206783
Co-reporter:Dr. Alberto Rodríguez-Pulido;Alina I. Kondrachuk;Dr. Deepak K. Prusty;Jia Gao;Dr. Maria A. Loi;Dr. Andreas Herrmann
Angewandte Chemie International Edition 2013 Volume 52( Issue 3) pp:
Publication Date(Web):
DOI:10.1002/anie.201209861
Co-reporter:Dr. Andreas A. Bastian;Eliza M. Warszawik;Praveen Puru; Christoph Arenz; Andreas Herrmann
Chemistry - A European Journal 2013 Volume 19( Issue 28) pp:9151-9154
Publication Date(Web):
DOI:10.1002/chem.201300912
Co-reporter:Dr. Alberto Rodríguez-Pulido;Alina I. Kondrachuk;Dr. Deepak K. Prusty;Jia Gao;Dr. Maria A. Loi;Dr. Andreas Herrmann
Angewandte Chemie 2013 Volume 125( Issue 3) pp:
Publication Date(Web):
DOI:10.1002/ange.201209861
Co-reporter:Diego Pesce, Yuzhou Wu, Anke Kolbe, Tanja Weil, Andreas Herrmann
Biomaterials 2013 34(17) pp: 4360-4367
Publication Date(Web):
DOI:10.1016/j.biomaterials.2013.02.038
Co-reporter:Tobias Schnitzler and Andreas Herrmann
Accounts of Chemical Research 2012 Volume 45(Issue 9) pp:1419
Publication Date(Web):June 22, 2012
DOI:10.1021/ar200211a
We live in a world full of synthetic materials, and the development of new technologies builds on the design and synthesis of new chemical structures, such as polymers. Synthetic macromolecules have changed the world and currently play a major role in all aspects of daily life. Due to their tailorable properties, these materials have fueled the invention of new techniques and goods, from the yogurt cup to the car seat belts. To fulfill the requirements of modern life, polymers and their composites have become increasingly complex. One strategy for altering polymer properties is to combine different polymer segments within one polymer, known as block copolymers. The microphase separation of the individual polymer components and the resulting formation of well defined nanosized domains provide a broad range of new materials with various properties. Block copolymers facilitated the development of innovative concepts in the fields of drug delivery, nanomedicine, organic electronics, and nanoscience.Block copolymers consist exclusively of organic polymers, but researchers are increasingly interested in materials that combine synthetic materials and biomacromolecules. Although many researchers have explored the combination of proteins with organic polymers, far fewer investigations have explored nucleic acid/polymer hybrids, known as DNA block copolymers (DBCs). DNA as a polymer block provides several advantages over other biopolymers. The availability of automated synthesis offers DNA segments with nucleotide precision, which facilitates the fabrication of hybrid materials with monodisperse biopolymer blocks. The directed functionalization of modified single-stranded DNA by Watson–Crick base-pairing is another key feature of DNA block copolymers. Furthermore, the appropriate selection of DNA sequence and organic polymer gives control over the material properties and their self-assembly into supramolecular structures. The introduction of a hydrophobic polymer into DBCs in aqueous solution leads to amphiphilic micellar structures with a hydrophobic polymer core and a DNA corona.In this Account, we discuss selected examples of recent developments in the synthesis, structure manipulation and applications of DBCs. We present achievements in synthesis of DBCs and their amplification based on molecular biology techniques. We also focus on concepts involving supramolecular assemblies and the change of morphological properties by mild stimuli. Finally, we discuss future applications of DBCs. DBC micelles have served as drug-delivery vehicles, as scaffolds for chemical reactions, and as templates for the self-assembly of virus capsids. In nanoelectronics, DNA polymer hybrids can facilitate size selection and directed deposition of single-walled carbon nanotubes in field effect transistor (FET) devices.
Co-reporter:Deepak K. Prusty;Minseok Kwak;Jur Wildeman ;Dr. Andreas Herrmann
Angewandte Chemie International Edition 2012 Volume 51( Issue 47) pp:11894-11898
Publication Date(Web):
DOI:10.1002/anie.201206006
Co-reporter:Deepak K. Prusty;Minseok Kwak;Jur Wildeman ;Dr. Andreas Herrmann
Angewandte Chemie 2012 Volume 124( Issue 47) pp:12064-12068
Publication Date(Web):
DOI:10.1002/ange.201206006
Co-reporter:Minseok Kwak and Andreas Herrmann  
Chemical Society Reviews 2011 vol. 40(Issue 12) pp:5745-5755
Publication Date(Web):22 Aug 2011
DOI:10.1039/C1CS15138J
This review provides an overview of a relatively new class of bio-conjugates, DNA amphiphiles, which consist of oligonucleotides covalently bonded to synthetic hydrophobic units. The reader will find the basic principles for the structural design and preparation methods of the materials. Moreover, the self-assembly into superstructures of higher order will be highlighted. Finally, some potential applications will be described.
Co-reporter:Moria Kwiat ; Roey Elnathan ; Minseok Kwak ; Jan Willem de Vries ; Alexander Pevzner ; Yoni Engel ; Larisa Burstein ; Artium Khatchtourints ; Amir Lichtenstein ; Eli Flaxer ; Andreas Herrmann ;Fernando Patolsky
Journal of the American Chemical Society 2011 Volume 134(Issue 1) pp:280-292
Publication Date(Web):November 15, 2011
DOI:10.1021/ja206639d
Functional interfaces of biomolecules and inorganic substrates like semiconductor materials are of utmost importance for the development of highly sensitive biosensors and microarray technology. However, there is still a lot of room for improving the techniques for immobilization of biomolecules, in particular nucleic acids and proteins. Conventional anchoring strategies rely on attaching biomacromolecules via complementary functional groups, appropriate bifunctional linker molecules, or non-covalent immobilization via electrostatic interactions. In this work, we demonstrate a facile, new, and general method for the reversible non-covalent attachment of amphiphilic DNA probes containing hydrophobic units attached to the nucleobases (lipid–DNA) onto SAM-modified gold electrodes, silicon semiconductor surfaces, and glass substrates. We show the anchoring of well-defined amounts of lipid–DNA onto the surface by insertion of their lipid tails into the hydrophobic monolayer structure. The surface coverage of DNA molecules can be conveniently controlled by modulating the initial concentration and incubation time. Further control over the DNA layer is afforded by the additional external stimulus of temperature. Heating the DNA-modified surfaces at temperatures >80 °C leads to the release of the lipid–DNA structures from the surface without harming the integrity of the hydrophobic SAMs. These supramolecular DNA layers can be further tuned by anchoring onto a mixed SAM containing hydrophobic molecules of different lengths, rather than a homogeneous SAM. Immobilization of lipid–DNA on such SAMs has revealed that the surface density of DNA probes is highly dependent on the composition of the surface layer and the structure of the lipid–DNA. The formation of the lipid–DNA sensing layers was monitored and characterized by numerous techniques including X-ray photoelectron spectroscopy, quartz crystal microbalance, ellipsometry, contact angle measurements, atomic force microscopy, and confocal fluorescence imaging. Finally, this new DNA modification strategy was applied for the sensing of target DNAs using silicon-nanowire field-effect transistor device arrays, showing a high degree of specificity toward the complementary DNA target, as well as single-base mismatch selectivity.
Co-reporter:Meryem S. Ayaz, Minseok Kwak, Fikri E. Alemdaroglu, Jie Wang, Rüdiger Berger and Andreas Herrmann  
Chemical Communications 2011 vol. 47(Issue 8) pp:2243-2245
Publication Date(Web):11 Jan 2011
DOI:10.1039/C0CC04746E
Ultra-high molecular weight DNA/polymer hybrid materials were prepared employing molecular biology techniques. Nucleic acid restriction and ligation enzymes were used to generate linear DNA di- and triblock copolymers that contain up to thousands of base pairs in the DNA segments.
Co-reporter:Anke Kolbe;Loretta L. del Mercato;Azhar Z. Abbasi;Pilar Rivera Gil;Sekineh J. Gorzini;Wim H. C. Huibers;Bert Poolman;Wolfgang J. Parak
Macromolecular Rapid Communications 2011 Volume 32( Issue 2) pp:186-190
Publication Date(Web):
DOI:10.1002/marc.201000491
Co-reporter:Minseok Kwak;Jia Gao;Deepak K. Prusty;Andrew J. Musser;Vladimir A. Markov;Dr. Nikolaos Tombros;Dr. Marc C. A. Stuart;Dr. Wesley R. Browne; Egbert J. Boekema;Dr. Gerrit tenBrinke;Harry T. Jonkman;Dr. Bart J. vanWees;Dr. Maria A. Loi;Dr. Andreas Herrmann
Angewandte Chemie International Edition 2011 Volume 50( Issue 14) pp:3206-3210
Publication Date(Web):
DOI:10.1002/anie.201007098
Co-reporter:Minseok Kwak ; Inge J. Minten ; Diana-Milena Anaya ; Andrew J. Musser ; Melanie Brasch ; Roeland J. M. Nolte ; Klaus Müllen ; Jeroen J. L. M. Cornelissen
Journal of the American Chemical Society 2010 Volume 132(Issue 23) pp:7834-7835
Publication Date(Web):May 19, 2010
DOI:10.1021/ja101444j
DNA amphiphile particles template formation of virus capsids and enable their loading.
Co-reporter:Deepak K. Prusty
Journal of the American Chemical Society 2010 Volume 132(Issue 35) pp:12197-12199
Publication Date(Web):August 16, 2010
DOI:10.1021/ja105181v
Fluorogenic reactions have recently emerged as a powerful tool for detection, diagnostics, and biosensing applications in a chemical and biological context. However, conventional fluorogenic systems reported to date rely on energy- or photoinduced electron transfer within the probes. Our communication demonstrates a conceptually new approach for generating a strong fluorescence signal through chemical bond formation mediated by a heavy-atom removal process. This method has favorable photophysical properties such as exceptional quantum yield and very low limits of fluorogenic DNA detection.
Co-reporter:Minseok Kwak, Andrew J. Musser, Jeewon Lee and Andreas Herrmann  
Chemical Communications 2010 vol. 46(Issue 27) pp:4935-4937
Publication Date(Web):04 Jun 2010
DOI:10.1039/C0CC00855A
We report the formation and characterisation of easily functionalisable mixed micelles with DNA/PEO corona and PPO core which can be loaded with hydrophobic molecules and stabilised by the formation of a cross-linked semi-interpenetrating network. Furthermore, the corona is functionalised by hybridisation either with dye-modified complementary DNA, with demonstrable distance control, or with DNA-labelled gold nanoparticles.
Co-reporter:Mukhles Sowwan;Maryam Faroun;Elad Mentovich;Imad Ibrahim;Shayma Haboush;Fikri Emrah Alemdaroglu;Minseok Kwak;Shachar Richter
Macromolecular Rapid Communications 2010 Volume 31( Issue 14) pp:1242-1246
Publication Date(Web):
DOI:10.1002/marc.200900904
Co-reporter:Mukhles Sowwan;Maryam Faroun;Elad Mentovich;Imad Ibrahim;Shayma Haboush;Fikri Emrah Alemdaroglu;Minseok Kwak;Shachar Richter
Macromolecular Rapid Communications 2010 Volume 31( Issue 14) pp:
Publication Date(Web):
DOI:10.1002/marc.201090037
Co-reporter:Milena Anaya;Minseok Kwak;Andrew J. Musser;Dr. Klaus Müllen;Dr. Andreas Herrmann
Chemistry - A European Journal 2010 Volume 16( Issue 43) pp:12852-12859
Publication Date(Web):
DOI:10.1002/chem.201001816

Abstract

This work describes the synthesis and characterization of a new family of DNA amphiphiles containing modified nucleobases. The hydrophobicity was imparted by the introduction of a dodec-1-yne chain at the 5-position of the uracil base, which allowed precise and simple tuning of the hydrophobic properties through solid-phase DNA synthesis. The micelles formed from these modified DNA sequences were characterized by atomic force microscopy, dynamic light scattering, and polyacrylamide gel electrophoresis. These experiments revealed the role of the quantity and location of the hydrophobic units in determining the morphology and stability of the micelles. The effects of hybridization on the physical characteristics of the DNA micelles were also studied; these results showed potential for the sequence-specific noncovalent functionalization of the self-assembled aggregates.

Co-reporter:Minseok Kwak ;Dr. Andreas Herrmann
Angewandte Chemie 2010 Volume 122( Issue 46) pp:8754-8768
Publication Date(Web):
DOI:10.1002/ange.200906820

Abstract

Die Entwicklung von Hybridstrukturen aus Biomakromolekülen und organischen Polymeren, die über kovalente Bindungen miteinander verknüpft sind, ist ein intensiv bearbeitetes Gebiet. Während die Kombination von Proteinen/Peptiden mit synthetischen Makromolekülen bereits umfassend untersucht worden ist, sind bisher weit weniger Beispiele für Nucleinsäure-Polymer-Hybride bekannt. In diesem Aufsatz stellen wir ausgewählte Beispiele dieser interessanten Materialklasse vor, deren Vertreter lineare Blockcopolymere, Seitenkettenpolymere oder vernetzte Strukturen sein können. Der Schwerpunkt liegt auf der Herstellung derartiger Materialien sowie auf möglichen Anwendungen in der Nanowissenschaft, Diagnostik und Biomedizin.

Co-reporter:Minseok Kwak ;Dr. Andreas Herrmann
Angewandte Chemie International Edition 2010 Volume 49( Issue 46) pp:8574-8587
Publication Date(Web):
DOI:10.1002/anie.200906820

Abstract

Extensive efforts have been devoted to the development of hybrid structures consisting of biomacromolecules and organic polymers connected through covalent bonds. While the combination of proteins and peptides with synthetic macromolecules has been explored in depth, far fewer examples of nucleic acid/polymer hybrids are known. In this Review we give selected examples of this exciting class of materials which can be arranged as linear block copolymer architectures, as side-chain polymers, or as cross-linked networks. Emphasis is placed on the fabrication of these materials as well as on their potential applications in nanoscience, diagnostics, and biomedicine.

Co-reporter:Fikri E. Alemdaroglu, Wei Zhuang, Lukas Zöphel, Jie Wang, Rüdiger Berger, Jürgen P. Rabe and Andreas Herrmann
Nano Letters 2009 Volume 9(Issue 10) pp:3658-3662
Publication Date(Web):July 21, 2009
DOI:10.1021/nl901899t
PCR was successfully implemented into polymer chemistry to produce linear multiblock structures up to pentablock architectures. Salient features of the generated DNA polymer hybrids were the ultrahigh molecular weights and their structural accuracy. Besides pushing the limits in block copolymer synthesis. a highly sophisticated characterization of the DNA/synthetic polymer hybrids was carried out by scanning force microscopy (SFM). Direct visualization revealed single polymer chains with the expected contour lengths for the DNA blocks and a characteristic kink at the central organic polymer unit bridging them. Furthermore, DNA triblock copolymers were manipulated by SFM, which so far has only been demonstrated for neat DNA and dendronized polymers. Upon blowing circular topologies, the DNA and the organic polymer chain have been extended and the contours of the three blocks could thereby be imaged separately.
Co-reporter:Fikri E. Alemdaroglu, Seth C. Alexander, Dongmei Ji, Deepak K. Prusty, Michael Börsch and Andreas Herrmann
Macromolecules 2009 Volume 42(Issue 17) pp:6529-6536
Publication Date(Web):August 13, 2009
DOI:10.1021/ma900727k
We present a new class of polymeric dyes bearing the difluoroboraindacene (BODIPY) chromophore within the main chain. Starting from a diiodinated BODIPY monomer, homo- and copolymers with a fully conjugated backbone were efficiently synthesized by transition-metal-catalyzed polycondensation reactions. The photophysical properties of the resulting polymeric materials were investigated in bulk and at the single molecule level. It was found that the BODIPY homopolymer resembles the absorption and emission properties of the individual BODIPY chromophore. In contrast, the copolymer products of 1,4-diethynylbenzene and benzene exhibit absorption and emission spectra that are shifted hypsochromically and bathochromically in regard to the homopolymer, respectively, allowing for easy color tuning by the choice of comonomers. The fluorescence quantum yield of the BODIPY homopolymer is remarkably high (57%). The exceptional brightness of the materials was confirmed in the single molecule investigations; the BODIPY homopolymer emitted several times more photons than the well-established fluorescent probe Rhodamine 6G with a quantum yield close to unity.
Co-reporter:FikriE. Alemdaroglu;Jie Wang;Michael Börsch Dr.;Rüdiger Berger Dr. Dr.
Angewandte Chemie 2008 Volume 120( Issue 5) pp:988-991
Publication Date(Web):
DOI:10.1002/ange.200703466
Co-reporter:FikriE. Alemdaroglu;Jie Wang;Michael Börsch Dr.;Rüdiger Berger Dr. Dr.
Angewandte Chemie International Edition 2008 Volume 47( Issue 5) pp:974-976
Publication Date(Web):
DOI:10.1002/anie.200703466
Co-reporter:Jun-O Jin, Haein Park, Wei Zhang, Jan Willem de Vries, Agnieszka Gruszka, Myung Won Lee, Dae-Ro Ahn, Andreas Herrmann, Minseok Kwak
Biomaterials (January 2017) Volume 115() pp:81-89
Publication Date(Web):January 2017
DOI:10.1016/j.biomaterials.2016.11.020
We introduce a versatile carrier system for in vitro and in vivo immune stimulation based on soft matter DNA nanoparticles (NPs). The incorporation of lipid-modified nucleotides into DNA strands enables the formation of micelles of uniform size. In a single self-assembly step, the micelles can be equipped with immune adjuvant (CpG) motifs and fluorescent probes. The immunological effects of CpG confined at the NP surface were studied in a comprehensive manner in animal experiments. Dose-dependent activation of spleen dendritic cells (DCs) by CpG-conjugated NP was observed, which was accompanied by the pronounced up-regulation of co-stimulatory molecule and cytokine production.
Co-reporter:Jun-O Jin, Haein Park, Wei Zhang, Jan Willem de Vries, Agnieszka Gruszka, Myung Won Lee, Dae-Ro Ahn, Andreas Herrmann, Minseok Kwak
Biomaterials (January 2017) Volume 115() pp:81-89
Publication Date(Web):January 2017
DOI:10.1016/j.biomaterials.2016.11.020
Co-reporter:Minseok Kwak and Andreas Herrmann
Chemical Society Reviews 2011 - vol. 40(Issue 12) pp:NaN5755-5755
Publication Date(Web):2011/08/22
DOI:10.1039/C1CS15138J
This review provides an overview of a relatively new class of bio-conjugates, DNA amphiphiles, which consist of oligonucleotides covalently bonded to synthetic hydrophobic units. The reader will find the basic principles for the structural design and preparation methods of the materials. Moreover, the self-assembly into superstructures of higher order will be highlighted. Finally, some potential applications will be described.
Co-reporter:Alexander Turkin, Lei Zhang, Alessio Marcozzi, Walter F. Mangel, Andreas Herrmann and Antoine M. van Oijen
Chemical Science (2010-Present) 2016 - vol. 7(Issue 2) pp:NaN920-920
Publication Date(Web):2015/10/07
DOI:10.1039/C5SC03063C
Numerous biological processes involve association of a protein with its binding partner, an event that is preceded by a diffusion-mediated search bringing the two partners together. Often hindered by crowding in biologically relevant environments, three-dimensional diffusion can be slow and result in long bimolecular association times. Similarly, the initial association step between two binding partners often represents a rate-limiting step in biotechnologically relevant reactions. We demonstrate the practical use of an 11-a.a. DNA-interacting peptide derived from adenovirus to reduce the dimensionality of diffusional search processes and speed up associations between biological macromolecules. We functionalize binding partners with the peptide and demonstrate that the ability of the peptide to one-dimensionally diffuse along DNA results in a 20-fold reduction in reaction time. We also show that modifying PCR primers with the peptide sled enables significant acceleration of standard PCR reactions.
Co-reporter:Lei Zhang, Lifei Zheng, Zhuojun Meng, Konstantin Balinin, Mark Loznik and Andreas Herrmann
Chemical Communications 2017 - vol. 53(Issue 47) pp:NaN6334-6334
Publication Date(Web):2017/05/26
DOI:10.1039/C7CC02500A
The speed-up of covalent bond formation was achieved between a sulfhydryl group and a 2-bromopropionic acid derivative by utilizing sliding peptide-modified substrates. Moreover, a new type of DNA cleaving reagent was developed, consisting of pVIc covalently coupled to verteporfin. This peptide–porphyrin conjugate allowed targeting of DNA and resulted in increased photodegradation of double-stranded nucleic acids.
Co-reporter:Meryem S. Ayaz, Minseok Kwak, Fikri E. Alemdaroglu, Jie Wang, Rüdiger Berger and Andreas Herrmann
Chemical Communications 2011 - vol. 47(Issue 8) pp:NaN2245-2245
Publication Date(Web):2011/01/11
DOI:10.1039/C0CC04746E
Ultra-high molecular weight DNA/polymer hybrid materials were prepared employing molecular biology techniques. Nucleic acid restriction and ligation enzymes were used to generate linear DNA di- and triblock copolymers that contain up to thousands of base pairs in the DNA segments.
Co-reporter:Minseok Kwak, Andrew J. Musser, Jeewon Lee and Andreas Herrmann
Chemical Communications 2010 - vol. 46(Issue 27) pp:NaN4937-4937
Publication Date(Web):2010/06/04
DOI:10.1039/C0CC00855A
We report the formation and characterisation of easily functionalisable mixed micelles with DNA/PEO corona and PPO core which can be loaded with hydrophobic molecules and stabilised by the formation of a cross-linked semi-interpenetrating network. Furthermore, the corona is functionalised by hybridisation either with dye-modified complementary DNA, with demonstrable distance control, or with DNA-labelled gold nanoparticles.
1H-Pyrrole-2-propanoic acid, 2,2,2-trichloroethyl ester
3-(4-methylphenyl)-1-pyridin-2-ylprop-2-en-1-one
LYSOZYME
EC 1.1.3.4
P-nitrophenylacetic acid*N-hydroxysuccinimide est
Formamide, N,N-dimethyl-
4-(hexyloxy)anilinium chloride
L-PHENYLALANINE