@article{AkarsuGrobeNowaczyketal.2021,
  author    = {Akarsu, Pinar and Grobe, Richard and Nowaczyk, Julius and Hartlieb, Matthias and Reinicke, Stefan and B{\"o}ker, Alexander and Sperling, Marcel and Reifarth, Martin},
  title     = {Solid-phase microcontact printing for precise patterning of rough surfaces},
  series = {ACS applied polymer materials},
  volume    = {3},
  journal   = {ACS applied polymer materials},
  number    = {5},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {2637-6105},
  doi       = {10.1021/acsapm.1c00024},
  pages     = {2420 -- 2431},
  year      = {2021},
  abstract  = {We present a microcontact printing (mu CP) routine suitable to introduce defined (sub-) microscale patterns on surface substrates exhibiting a high capillary activity and receptive to a silane-based chemistry. This is achieved by transferring functional trivalent alkoxysilanes, such as (3-aminopropyl)-triethoxysilane (APTES) as a low-molecular weight ink via reversible covalent attachment to polymer brushes grafted from elastomeric polydimethylsiloxane (PDMS) stamps. The brushes consist of poly{N-[tris(hydroxymethyl)-methyl]acrylamide} (PTrisAAm) synthesized by reversible addition-fragmentation chain-transfer (RAFT)-polymerization and used for immobilization of the alkoxysilane-based ink by substituting the alkoxy moieties with polymer-bound hydroxyl groups. Upon physical contact of the silane-carrying polymers with surfaces, the conjugated silane transfers to the substrate, thus completely suppressing ink-flow and, in turn, maximizing printing accuracy even for otherwise not addressable substrate topographies. We provide a concisely conducted investigation on polymer brush formation using atomic force microscopy (AFM) and ellipsometry as well as ink immobilization utilizing two-dimensional proton nuclear Overhauser enhancement spectroscopy (H-1-H-1-NOESY-NMR). We analyze the mu CP process by printing onto Si-wafers and show how even distinctively rough surfaces can be addressed, which otherwise represent particularly challenging substrates.},
  language  = {en}
}
@article{LaroqueReifarthSperlingetal.2020,
  author    = {Laroque, Sophie and Reifarth, Martin and Sperling, Marcel and Kersting, Sebastian and Kloepzig, Stefanie and Budach, Patrick and Hartlieb, Matthias and Storsberg, Joachim},
  title     = {Impact of multivalence and self-assembly in the design of polymeric antimicrobial peptide mimics},
  series = {ACS applied materials \& interfaces},
  volume    = {12},
  journal   = {ACS applied materials \& interfaces},
  number    = {27},
  publisher = {American Chemical Society},
  address   = {Washington},
  issn      = {1944-8244},
  doi       = {10.1021/acsami.0c05944},
  pages     = {30052 -- 30065},
  year      = {2020},
  abstract  = {Antimicrobial resistance is an increasingly serious challenge for public health and could result in dramatic negative consequences for the health care sector during the next decades. To solve this problem, antibacterial materials that are unsusceptible toward the development of bacterial resistance are a promising branch of research. In this work, a new type of polymeric antimicrobial peptide mimic featuring a bottlebrush architecture is developed, using a combination of reversible addition-fragmentation chain transfer (RAFT) polymerization and ring-opening metathesis polymerization (ROMP). This approach enables multivalent presentation of antimicrobial subunits resulting in improved bioactivity and an increased hemocompatibility, boosting the selectivity of these materials for bacterial cells. Direct probing of membrane integrity of treated bacteria revealed highly potent membrane disruption caused by bottlebrush copolymers. Multivalent bottlebrush copolymers clearly outperformed their linear equivalents regarding bioactivity and selectivity. The effect of segmentation of cationic and hydrophobic subunits within bottle brushes was probed using heterograft copolymers. These materials were found to self-assemble under physiological conditions, which reduced their antibacterial activity, highlighting the importance of precise structural control for such applications. To the best of our knowledge, this is the first example to demonstrate the positive impact of multivalence, generated by a bottlebrush topology in polymeric antimicrobial peptide mimics, making these polymers a highly promising material platform for the design of new bactericidal systems.},
  language  = {en}
}
@article{SperlingReifarthGrobeetal.2019,
  author    = {Sperling, Marcel and Reifarth, Martin and Grobe, Richard and B{\"o}ker, Alexander},
  title     = {Tailoring patches on particles: a modified microcontact printing routine using polymer-functionalised stamps},
  series = {Chemical communications},
  volume    = {55},
  journal   = {Chemical communications},
  number    = {68},
  publisher = {Royal Society of Chemistry},
  address   = {Cambridge},
  issn      = {1359-7345},
  doi       = {10.1039/c9cc03903a},
  pages     = {10104 -- 10107},
  year      = {2019},
  abstract  = {Herein, we report a modified microcontact printing (mu CP) routine suitable to introduce particle patches of a low molecular weight ink (LMWI) on porous SiO2 microparticles. Thereby, patch precision could be significantly improved by utilising stamps which have been surface-functionalised with grafted polymers. This improvement was evaluated by a profound software-assisted statistical analysis.},
  language  = {en}
}
@article{WangSperlingReifarthetal.2020,
  author    = {Wang, Xuepu and Sperling, Marcel and Reifarth, Martin and B{\"o}ker, Alexander},
  title     = {Shaping metallic nanolattices},
  series = {Small},
  volume    = {16},
  journal   = {Small},
  number    = {11},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {1613-6810},
  doi       = {10.1002/smll.201906721},
  pages     = {1 -- 8},
  year      = {2020},
  abstract  = {A method for the fabrication of well-defined metallic nanostructures is presented here in a simple and straightforward fashion. As an alternative to lithographic techniques, this routine employs microcontact printing utilizing wrinkled stamps, which are prepared from polydimethylsiloxane (PDMS), and includes the formation of hydrophobic stripe patterns on a substrate via the transfer of oligomeric PDMS. Subsequent backfilling of the interspaces between these stripes with a hydroxyl-functional poly(2-vinyl pyridine) then provides the basic pattern for the deposition of citrate-stabilized gold nanoparticles promoted by electrostatic interaction. The resulting metallic nanostripes can be further customized by peeling off particles in a second microcontact printing step, which employs poly(ethylene imine) surface-decorated wrinkled stamps, to form nanolattices. Due to the independent adjustability of the period dimensions of the wrinkled stamps and stamp orientation with respect to the substrate, particle arrays on the (sub)micro-scale with various kinds of geometries are accessible in a straightforward fashion. This work provides an alternative, cost-effective, and scalable surface-patterning technique to fabricate nanolattice structures applicable to multiple types of functional nanoparticles. Being a top-down method, this process could be readily implemented into, e.g., the fabrication of optical and sensing devices on a large scale.},
  language  = {en}
}