Antimicrobial peptides (AMPs) provide protection against a variety of pathogenic bacteria and are, therefore, an important part the innate immune system. Over past decade, there has been considerable interest in developing AMPs as intravenously administered antibiotics. However, despite extensive efforts pharmaceutical biotechnology industry, it proven difficult to achieve this goal. While researchers have solved some relatively simple problems such susceptibility proteolysis, more severe...

Amphiphilic cationic polynorbornene derivatives, soluble in water, were prepared from modular norbornene monomers, with a wide range of molecular weights (Mn = 1600−137 500 g/mol) and narrow polydispersities (PDI 1.1−1.3). The antibacterial activity determined by growth inhibition assays the hemolytic against human red blood cells measured compared to determine selectivity polymers for bacterial over mammalian cells. effects monomer repeat unit hydrophobicity polymer weight on activities...

The design of polymers and oligomers that mimic the complex structures remarkable biological properties proteins is an important endeavor with both fundamental practical implications. Recently, a number nonnatural peptides designed sequences have been elaborated to provide biologically active structures; in particular, facially amphiphilic built from β-amino acids shown as well function natural antimicrobial such magainins cecropins. However, these their β-peptide analogues are expensive...

Synthetic Mimics of Antimicrobial Peptides (SMAMPs) imitate natural host-defense peptides, a vital component the body’s immune system. This work presents molecular construction kit that allows easy and versatile synthesis broad variety facially amphiphilic oxanorbornene-derived monomers. Their ring-opening metathesis polymerization (ROMP) deprotection provide several series SMAMPs. Using amphiphilicity, monomer feed ratio, weight as parameters, polymers with 533 times higher selectivitiy...

Here we present the first metal-cation-based anion exchange membranes (AEMs), which were synthesized by copolymerization and cross-linking of a norbornene monomer functionalized with water-soluble bis(terpyridine)ruthenium(II) complex dicyclopentadiene. Each ruthenium has two associated counteranions, unlike most ammonium- phosphonium-based single cation–anion pairs. The resulting AEMs show conductivities mechanical properties comparable to those traditional quaternary-ammonium-based as well...

Abstract Although the peak power density of anion exchange membrane fuel cells (AEMFCs) has been raised from ≈0.1 to ≈1.4 W cm −2 over last decade, a majority AEMFCs reported in literature have not demonstrated achieve consistently high performance and steady‐state operation. Poly(olefin)‐based AEMs with fluorine substitution on aromatic comonomer show considerably higher dimensional stability compared samples that do contain fluorine. More importantly, fluorinated poly(olefin)‐based exhibit...

It has long been recognized that cationic nanoparticles induce cell membrane permeability. Recently, it found the formation and/or growth of nanoscale holes in supported lipid bilayers. In this paper, we show noncytotoxic concentrations 30−2000 pA currents 293A (human embryonic kidney) and KB epidermoid carcinoma) cells, consistent with a defect such as single hole or group ranging from 1 to 350 nm2 total area. Other forms defects, including nanoparticle porating agents adsorbing onto...

Polyguanidinium oxanorbornene (PGON) was synthesized from norbornene monomers via ring-opening metathesis polymerization. This polymer observed to be strongly antibacterial against Gram-negative and Gram-positive bacteria as well nonhemolytic human red blood cells. Time-kill studies indicated that this is lethal not just bacteriostatic. In sharp contrast previously reported SMAMPs (synthetic mimics of antimicrobial peptides), PGON did disrupt membranes in vesicle-dye leakage assays...

To guide the development of tissue scaffolds and characterization naturally heterogeneous biological tissues, we have developed a method to determine local modulus at an arbitrary point within soft material. The involves growing cavity tip syringe needle monitoring pressure onset mechanical instability. This critical is directly related results focus on network poly(lactide)-poly(ethylene oxide)-poly(lactide) triblock copolymer poly(vinyl alcohol) hydrogels. These materials serve as model...

New and interesting properties can be obtained from macromolecular architectures functionalized with supramolecular moieties, particularly metal-ligand complexes. Self-assembly, based on the selective control of noncovalent interactions, guides creation hierarchically ordered materials providing access to novel structures new properties. This field has expanded significantly in last two decades, one most ubiquitous functionalities is terpyridine. Despite its wide-spread use, much basic...

Abstract In this study, amphiphilic polyoxanorbornene with different quaternary alkyl pyridinium side chains were synthesized. The biological efficiencies of these polymers, various substituents, determined by bacterial growth inhibition assays and hemolytic activity (HC 50 ) against human red blood cells (RBCs) to provide selectivity polymers for over mammalian cells. A series substituents (ethyl, butyl, hexyl, octyl, decyl phenylethyl) two molecular weights (3 10 kDa) prepared. impact...

We have investigated how doubly selective synthetic mimics of antimicrobial peptides (SMAMPs), which can differentiate not only between bacteria and mammalian cells, but also Gram-negative Gram-positive bacteria, make the latter distinction. By dye-leakage experiments on model vesicles complementary we were able to relate Gram selectivity structural differences these types. showed that double membrane E. coli rather than difference in lipid composition S. aureus was responsible for...

Cyclic poly(5-hydroxy-1-cyclooctene) (PACOE) was synthesized by ring-expansion metathesis polymerization (REMP), and thiol-ene chemistry used to cross-link the internal double bonds in PACOE backbone. This created a novel network material (gels formed from cyclic polymers) with unique structural units, where main chains, which serve as secondary topological cross-linkages, were connected primary intermolecular chemical cross-linkages. The resulting properties notably different those of...

The current study is aimed at investigating the effect of fine-tuning cationic character synthetic mimics antimicrobial peptides (SMAMPs) on hemolytic and antibacterial activities. A series novel norbornene monomers that carry one, two, or three Boc-protected amine functionalities was prepared. Ring-opening metathesis polymerization (ROMP) monomers, followed by deprotection groups resulted in polynorbornenes charges per monomer repeat unit. Increasing number most hydrophobic polymer reduced...

Highly resilient synthetic hydrogels were synthesized by using the efficient thiol-norbornene chemistry to cross-link hydrophilic poly(ethylene glycol) (PEG) and hydrophobic polydimethylsiloxane (PDMS) polymer chains. The swelling mechanical properties of controlled relative amounts PEG PDMS. fracture toughness (G(c)) was increased 80 J/m(2) as water content hydrogel decreased from 95% 82%. In addition, energy storage efficiency (resilience) more than 97% at strains up 300%. This is...

Two unique molecular templates for generating polymeric materials with a cyclic architecture were developed by combining ring-expansion metathesis polymerization and click chemistry. These two universal polymers used in three examples to demonstrate the wide range of potential enabled. They include functional polymers, polymer brushes, gels.

As a semipermeable barrier that controls the flux of biomolecules in and out cell, plasma membrane is critical cell function survival. Many proteins interact with modulate its physiology. Within this large landscape membrane-active molecules, researchers have focused significant attention on two specific classes peptides, antimicrobial peptides (AMPs) penetrating (CPPs), because their unique properties. In Account, we describe our efforts over last decade to build understand synthetic mimics...

Cavitation is the sudden, unstable expansion of a void or bubble within liquid solid subjected to negative hydrostatic stress. rheology field emerging from development suite materials characterization, damage quantification, and therapeutic techniques that exploit physical principles cavitation. inherently complex broad in scope with wide-ranging applications biology, chemistry, materials, mechanics communities. This perspective aims drive collaboration among these communities guide...

Polymer networks are critically important for numerous applications including soft biomaterials, adhesives, coatings, elastomers, and gel-based materials energy storage. One long-standing challenge these present lies in understanding the role of network defects, such as dangling ends loops, developed during cross-linking. These defects can negatively impact physical, mechanical, transport properties gel. Here we report chemically cross-linked poly(ethylene glycol) (PEG) gels formed through a...

Bromoalkyl-functionalized poly(olefin)s were synthesized by copolymerization of 4-(4-methylphenyl)-1-butene with 11-bromo-1-undecene using Ziegler–Natta polymerization. The resulting bromoalkyl-functionalized converted to quaternary ammonium-containing anion-conductive copolymers reacting the pendant bromoalkyl group trimethylamine or a custom-synthesized tertiary amine containing ammonium moieties. Poly(olefin)-based AEMs three cations per side chain showed considerably higher hydroxide...

A family of nine poly(ether–thioethers) (PETEs) were synthesized by the radical coupling a dithiol and divinyl ether to investigate importance organo-sulfur incorporation in solid polymer electrolytes. Two series four polymers each probe both effect carbon spacer length between thioether units ratio units. PETE samples from these two had low Tg values, ranging −50 −75 °C, all but PETEs displayed crystallinity. Molecular weights 7 13 kg/mol obtained for polymers. Taking advantage...