Abstract Recent years have seen increasing interest in the construction of nanoscopically layered materials involving aqueous‐based sequential assembly polymers on solid substrates. In booming research area layer‐by‐layer (LbL) oppositely charged polymers, self‐assembly driven by hydrogen bond formation emerges as a powerful technique. Hydrogen‐bonded (HB) LbL open new opportunities for films, which are more difficult to produce than their electrostatically assembled counterparts....

We explore responsive properties of hollow multilayer shells tannic acid assembled with a range neutral polymers, poly(N-vinylpyrrolidone) (PVPON), poly(N-vinylcaprolactam) (PVCL) or poly(N-isopropylacrylamide) (PNIPAM). found that the nanoscale fabricated through hydrogen-bonded layer-by-layer (LbL) assembly can be tuned changing interaction strength polymer acid, and by change in counterpart hydrophobicity. Unlike most LbL films two components, produced acid-based are extremely stable wide...

We summarize existing knowledge and present some new results on the relationship between polyelectrolyte multilayer (PEM) growth phase behavior of complexes (PECs) in solution. Detailed understanding competition surface solution as applied to PEMs requires selective labeling polymers and/or application techniques that allow chemically specific monitoring film components, such in-situ ATR−FTIR spectroscopy. The trends observed with multilayers directly follow from properties PECs Effects a...

Hydrogen-bonded multilayers of a neutral polymer (poly(N-vinylpyrrolidone), PVPON) with poly(methacrylic acid) (PMAA) were used as templates to introduce cross-links between PMAA layers using carbodiimide chemistry and ethylenediamine cross-linking agent. Upon exposure high pH, PVPON is completely released from the hydrogel matrix, producing surface-attached hydrogels. When such hydrogels are deposited at surface silica particles, particle core subsequently dissolved, hollow one-component...

Layer-by-layer assembly of polyelectrolyte multilayer (PEM) films represents a bottom-up approach for re-engineering the molecular landscape cell surfaces with spatially continuous and molecularly uniform ultrathin films. However, fabricating PEMs on viable cells has proven challenging owing to high cytotoxicity polycations. Here, we report rational engineering new class modular biological functionality tunable physicochemical properties which have been engineered abrogate cytotoxicity....

New developments in the area of hydrogen‐bonded layer‐by‐layer assembly composed weak polyelectrolytes are reviewed, with emphasis on self‐assembly an aqueous environment. Advances fundamental understanding polymer layering at surfaces addressed. The effects molecular weight polymers, ionic strength, pH, and temperature growth post‐self‐assembly response films summarized contrasted trends known for electrostatically assembled films. Deposition onto particulate substrates properties produced...

Abstract Though transplantation of pancreatic islet cells has emerged as a promising treatment for Type 1 diabetes its clinical application remains limited due to number limitations including both pathogenic innate and adaptive immune responses. This paper reports on novel type multifunctional cytoprotective material applied coat living islets. The coating utilizes hydrogen‐bonded interactions natural polyphenol (tannic acid) with poly(N‐vinylpyrrolidone) deposited the surface via non‐ionic...

We report ultrathin pH-responsive plasmonic membranes of [poly(methacrylic acid)-gold nanorods]20 (PMAA-Au NRs)20 with gold nanorods embedded into swollen cross-linked LbL hydrogels. In contrast to the most known pH responsive materials which rely on pH-triggered change in intensity photoluminescence or plasmon bands, structures suggested here exhibit a significant shift easily detectable, strong resonance band. show that pH-induced deswelling hydrogel film from 8 5 causes dramatic...

We report on a novel type of triblock copolymer polymersomes with temperature-controlled permeability within the physiologically relevant temperature range 37–42 °C for sustained delivery anticancer drugs. These combine characteristics liposomes, such as biocompatibility, biodegradability, monodispersity, and stability at room temperature, tunable size thermal responsiveness provided by amphiphilic copolymers. The temperature-sensitive...

Hydrogen-bonded layer-by-layer capsules of tannic acid were used for highly efficient doxorubicin encapsulation and storage in the pH range 5 < 7.5.

We report on naturally inspired hydrogel capsules with pH-induced transitions from discoids to oblate ellipsoids and their interactions cells. integrate characteristics of erythrocytes such as discoidal shape, hollow structure, elasticity reversible pH-responsiveness poly(methacrylic acid) (PMAA) design a new type drug delivery carrier be potentially triggered by chemical stimuli in the tumor lesion. The are fabricated cross-linked PMAA multilayers using sacrificial discoid silicon...

Despite the accessibility of ultrasound, clinical potential ultrasound-active theranostic agents has not been fully realized because it requires combining sufficient imaging contrast, high encapsulation efficiency, and ultrasound-triggered release in one entity. We report on polymer microcapsules composed hydrogen-bonded multilayers tannic acid poly(N-vinylpyrrolidone) that produce contrast deliver anticancer drug doxorubicin upon low-power diagnostic or high-power therapeutic ultrasound...

The formation of polyelectrolyte multilayers using the layer-by-layer sequential self-assembly a weak polybase and polyacid onto surface Si crystal their stability under acidic conditions were studied. system was 12%, 20%, 25%, 37%, 90%, or 98% quaternized poly-4-vinylpyridine (Q12, Q20, Q25, Q37, Q90, Q98) as polybases (generally abbreviated QPVP) poly(methacrylic acid) (PMAA) in buffered D2O. adsorption ionization pyridine rings carboxylic groups quantified Fourier transform infrared...

Neutral temperature responsive polymers, such as poly(N-vinylcaprolactam) (PVCL) and poly(vinyl methyl ether) (PVME), were included in ultrathin films using layer-by-layer alternating adsorption of these polymers with poly(methacrylic acid) (PMAA) at low pH. The amounts adsorbed ionization carboxylic groups within a film quantified situ FTIR-ATR (Fourier transform infrared spectroscopy by attenuated total reflection). strength interlayer adhesion provided through hydrogen-bonding...

Thin films obtained from a layer-by-layer deposition of weak polycarboxylic acid and positively charged globular protein were studied by in situ ATR-FTIR. The system was chicken egg lysozyme (Lys), bovine pancrease ribonuclease A (RNase), or γ-globulin (IgG) self-assembled with acids. When the pH value lowered below critical point, growth their tolerance to decomposition added sodium chloride improved dramatically. Stabilization protein/polyacid salt solutions at lower values occurred due...

We apply neutron reflectivity to probe the internal structure of spin-assisted layer-by-layer (SA-LbL) films composed electrostatically assembled polyelectrolytes. find that level stratification and degree layer intermixing can be controlled by varying type concentration salt during SA-LbL assembly. observe well-defined in when deposited from salt-free solutions. These feature 2-nm-thick bilayers, which are approximately 3-fold thicker than those conventional LbL under similar conditions....

We report on nanothin multilayer hydrogels of cross-linked poly(N-vinylcaprolactam) (PVCL) that exhibit distinctive and reversible thermoresponsive behavior. The single-component PVCL were produced by selective cross-linking in layer-by-layer films PVCL-NH(2) copolymers assembled with poly(methacrylic acid) (PMAA) via hydrogen bonding. degree the hydrogel film shrinkage, defined as ratio wet thicknesses at 25°C to 50°C, was demonstrated be 1.9±0.1 1.3±0.1 for made from PVCL-NH(2)-7...

Type 1 diabetes is an autoimmune‐mediated disease resulting in the destruction of insulin‐secreting pancreatic β ‐cells. Transplantation insulin‐producing islets a viable treatment to restore euglycemia diabetics; however, clinical application remains limited due use toxic immunosuppressive therapies prevent immune‐mediated rejection. A nanothin polymer material with dual antioxidant and properties capable modulating both innate adaptive immune responses crucial for transplantation outcome...

We demonstrated a simple and facile approach to fabricate biocompatible monodisperse hollow microparticles of controlled geometry. The hemispherical, spherical, cubical are obtained by drying multilayer capsules hydrogen-bonded poly(N-vinylpyrrolidone)/tannic acid (PVPON/TA)n. Drying spherical results in hemispherical particles if 15 < n 20. This shape transformation is capsule stiffness, which regulated the layer number, diameter, PVPON molecular weight. Cubical maintaining their...

We report on weak polyacid brushes with highly tunable pH and temperature response characteristics. This was achieved by synthesizing a series of homo- copolymers which contain 2-alkylacrylic acids (aAAs) increased hydrophobicity, i.e. acrylic acid (AA), methacrylic (MAA), or 2-ethylacrylic (EAA), using surface-initiated reversible addition–fragmentation chain transfer (SI-RAFT) polymerization. As revealed contact angle measurements, in situ ellipsometry AFM studies brush swelling, the...

Shape and responsiveness of nanoengineered delivery carriers are crucial characteristics for rapid efficient therapeutics. We report on a novel type micrometer-sized hydrogel particles controlled shape with dual pH- redox-sensitivity intracellular anticancer drugs. The cubical spherical poly(methacrylic acid) (PMAA) networks disulfide links obtained by cross-linking PMAA cystamine within hydrogen-bonded multilayers PMAA/poly(vinylpyrrolidone) (PMAA/PVPON) sacrificial mesoporous templates....

We present synthesis and assembly of novel thermoresponsive block copolymers with double LCST precisely controlled within the physiological temperature range. Two separate phase transition temperatures were achieved by RAFT polymerization structurally similar monomers varied hydrophobicity. The LCST1 was from 19 to 27 °C copolymerization N-vinylcaprolactam a hydrophobic monomer, 3-methyl-N-vinylcaprolactam, while LCST2 at 41-42 attained hydrophilic N-vinylpyrrolidone. facilitates micelle...