Supramolecular adhesives inspired from adhesive proteins and nucleic acids: molecular design, properties, and applications.

Bioinspired supramolecular adhesives have been recently emerging as novel functional materials, which have shown a wide range of applications in wearable sensors and tissue engineering such as tissue adhesives and wound dressings. In this review, we summarize and discuss two main types of biologically inspired supramolecular adhesives from adhesive proteins and nucleic acids. The widely studied catechol-based adhesives, that originated from adhesive proteins of marine organisms such as mussels, and recently emerging nucleobase-containing supramolecular adhesives are both introduced and discussed.

Complementary Nucleobase-Containing Double-Network Elastomers with High Energy Dissipation and Room-Temperature Fast Recovery.

Elastomers have been widely employed in various industrial products such as tires, actuators, dampers, and sealants. While various methods have been developed to strengthen elastomers, achieving continuously high energy dissipation with fast room-temperature recovery remains challenging, prompting the need for further structural optimization. Herein, high energy dissipated and fast recoverable double-network (DN) elastomers are fabricated, in which the supramolecular polymers of complementary adenine and thymine serve as the first network and the covalently cross-linked soft polymer as the second network.

Bioinspired and biomimetic nucleobase-containing polymers: the effect of selective multiple hydrogen bonds.

Bioinspired and biomimetic nucleobase-containing polymers are a series of polydisperse nucleic acid analogs, mainly obtaining through highly efficient and scalable step-growth or chain polymerizations. The combination of pendant nucleobase groups and various backbones endows the polymers/materials with selective multiple H-bonds under distinct conditions, demonstrating the broad applicability of this new family of polymeric materials. In this perspective, we critically summarize recent advances of bioinspired and biomimetic nucleobase-containing polymers and materials in both solution and the bulk.

Wetting-enhanced adhesion of photo-polymerized supramolecular adhesives for both smooth and rough surfaces.

Efficient interactions between an adhesive and a substrate surface at the molecular level are the basis for the formation of robust adhesion, which substantially relies on interfacial wetting. However, strong adhesives usually improve cohesion but compromise interfacial properties. Herein, we have reported a kind of robust supramolecular adhesive based on the outstanding mobility and interfacial wettability of adhesive precursors.

Morphological Transformation and Surface Engineering of Glycovesicles Driven by Bioinspired Hydrogen Bonds of Nucleobases.

Glycopolymer-based supramolecular glycoassemblies with signal-driven cascade morphological deformation and accessible surface engineering toward bioinspired functional glycomaterials have attracted much attention due to their diverse applications in fundamental and practical scenarios. Herein, we achieved the cascade morphological transformation and surface engineering of a nucleobase-containing polymeric glycovesicle through exploiting the bioinspired complementary multiple hydrogen bonds of complementary nucleobases. First, the synthesized thymine-containing glycopolymers (PGal--PTAm) are capable of self-assembling into well-defined glycovesicles.

Structure-Controllable and Mass-Produced Glycopolymersomes as a Template of the Carbohydrate@Ag Nanobiohybrid with Inherent Antibacteria and Biofilm Eradication.

Glycopolymer-supported silver nanoparticles (AgNPs) have demonstrated a promising alternative to antibiotics for the treatment of multidrug-resistant bacteria-infected diseases. In this contribution, we report a class of biohybrid glycopolymersome-supported AgNPs, which are capable of effectively killing multidrug-resistant bacteria and disrupting related biofilms. First of all, glycopolymersomes with controllable structures were massively fabricated through reversible addition-fragmentation chain transfer (RAFT) polymerization-induced self-assembly (PISA) in an aqueous solution driven by complementary hydrogen bonding interaction between the pyridine and amide groups of -(2-methylpyridine)-acrylamide (MPA) monomers.

Counterion-Mediated Hydrogen Bonding Making Poly(styrenesulfonate)-Based Strong Polyelectrolytes pH-Responsive.

Owing to the well-established fact that poly(styrenesulfonate) (PSS)-based strong polyelectrolytes are pH insensitive, their applications in smart materials have thus been severely limited. However, we demonstrate here that counterion-mediated hydrogen bonding (CMHB) makes the PSS brush pH-responsive. With decreasing pH, more hydrogen bonds are formed between the bound hydronium counterions and the sulfonate (-SO) groups in the PSS brush.

Bioinspired nucleobase-containing polyelectrolytes as robust and tunable adhesives by balancing the adhesive and cohesive properties.

Supramolecular polymeric adhesives inspired by nature have been strongly pursued by scientists, since they possess strong but dynamic reversible adhesive behaviors concurrently. Optimizing the adhesive and cohesive properties is of vital importance for the fabrication of strong supramolecular polymeric adhesives, but common strategies often strengthen one property at the expense of another. Herein, counterion exchange of nucleobase-containing polyelectrolyte adhesives was utilized to boost the interfacial adhesion without compromising the intermolecular cohesion, achieving high adhesion strengths.

Improving the performance of supercapacitors by combining polymeric redox couples and a polymer hydrogel separator.

Based on a combination of polymeric redox couples and a polymer hydrogel separator, the performance of aqueous supercapacitors can be improved by concurrently increasing the specific capacitance, widening the electrolyte decomposition window, improving the cycling performance, and suppressing the self-discharge of both the electrical double-layer and faradaic charge storage.

Effect of Counterion-Mediated Hydrogen Bonding on Polyelectrolytes at the Solid/Water Interface: Current Understanding and Perspectives.

The counterion-mediated hydrogen bonding (CMHB) effect can be generated in polyelectrolyte systems when hydrogen bonds are formed between the bound counterions and polyelectrolyte chains. This Perspective mainly discusses the effect of CMHB on polyelectrolytes at the solid/water interface. The CMHB effect generated by the hydroxide (OH) or hydronium (HO) counterions gives rise to a pH responsiveness of strong polyelectrolyte brushes (SPBs) whose strength can be modulated by the external salt concentration.

Core-Shell Polymeric Nanostructures with Intracellular ATP-Fueled dsRNA Delivery toward Genetic Control of Insect Pests.

Transgenic RNA interference (RNAi) represents a burgeoning and promising alternative avenue to manage plant diseases and insect pests in plants. Nonviral nanostructured dsRNA carriers have been demonstrated to possess great potential to facilitate the application of RNAi. However, it remains a critical challenge to achieve the targeted and effective release of dsRNA into the pest cells, limiting the efficiency of the biological control of pests and diseases in practical applications.

Adenosine Triphosphate-Responsive Glyconanorods through Self-Assembly of β-Cyclodextrin-Based Glycoconjugates for Targeted and Effective Bacterial Sensing and Killing.

Polymer-based nanomaterials have exhibited promising alternative avenues to combat the globe challenge of multidrug-resistant bacterial infection. However, most of the reported polymeric nanomaterials have facially linear amphiphilic structures with positive net charges, which may lead to nonspecific binding, high hemolysis, and uncontrollable self-organization, limiting their practical applications. In this contribution, we report a one-dimensional glyconanorod (GNR) through self-assembly of well-defined β-cyclodextrin-based glycoconjugates (RMan) featuring hydrophobic carbon-based chains and amide rhodamines with an adenosine triphosphate (ATP)-recognition site and targeted and hydrophilic mannoses and positively net-charged ethylene amine groups.

The positive impact of informal spousal caregiving on the physical activity of older adults.

Introduction: Although physical activity (PA) is crucial for health, the literature is mixed about how individuals' PA decisions are affected by their spouses. To fill this gap, we examined the extent to which providing care for one spouse affects the PA of the other spouse among those aged 50 or older in the United States.

Methods: We analyzed 9,173 older adults living with their spouses or partners from the 2004 to 2016 waves of the Health and Retirement Study.

Dynamic Glycopeptide Dendrimers: Synthesis and Their Controllable Self-Assembly into Varied Glyco-Nanostructures for the Biomimicry of Glycans.

A library of 14 dynamic glycopeptide amphiphilic dendrimers composed of 14 hydrophilic and bioactive saccharides (seven kinds) as dendrons and 7 hydrophobic peptides (di- and tetrapeptides) as arms with β-cyclodextrin (CD) as a core were facially designed and synthesized in several steps. Fourteen saccharides were first conjugated to the C-2 and C-3 positions of CD, forming glycodendrons. Subsequently, seven oligopeptide arms were introduced at the C-6 positions of a CD moiety by an acylhydrazone dynamic covalent bond, resulting in unique Janus amphiphilic glycopeptide dendrimers with precise and varied molecular structures.

TEMPO-Functionalized Nanoreactors from Bottlebrush Copolymers for the Selective Oxidation of Alcohols in Water.

Polymeric nanoreactors in water fabricated by the self-assembly of amphiphilic copolymers have attracted much attention due to their good catalytic performance without using organic solvents. However, the disassembly and instability of relevant nanostructures often compromise their potential applicability. Herein, the preparation of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-containing nanoreactors by the self-assembly of amphiphilic bottlebrush copolymers has been demonstrated.

Specific Anion Effects on Charged-Neutral Random Copolymers: Interplay between Different Anion-Polymer Interactions.

The study of ion specificities of charged-neutral random copolymers is of great importance for understanding specific ion effects on natural macromolecules. In the present work, we have investigated the specific anion effects on the thermoresponsive behavior of poly([2-(methacryloyloxy)ethyl trimethylammonium chloride]---isopropylacrylamide) [P(METAC--NIPAM)] random copolymers. Our study demonstrates that the anion specificities of the P(METAC--NIPAM) copolymers are dependent on their chemical compositions.

Supramolecular nucleobase-functionalized polymers: synthesis and potential biological applications.

Nucleobase-functionalized covalent polymers are attracting great attention owing to their versatile structures, accessible architectures and robust properties. Although these materials are still inferior compared with DNA-based materials, they have demonstrated tremendous potential for more sophisticated applications in the biomedical field. In this review, we focus on recent advances concerning these materials.

Modulating Morphologies and Surface Properties of Nanoparticles from Cellulose-Grafted Bottlebrush Copolymers Using Complementary Hydrogen-Bonding between Nucleobases.

Herein we report the synthesis of a cellulose-grafted bottlebrush copolymer with nucleobases as hydrophobic moieties. Well-defined spherical micelles from this bottlebrush copolymer were fabricated via a solvent switch method. A morphological transition from spheres to worms was only observed to occur when a diblock copolymer with a complementary nucleobase functionality was introduced.

Anisotropic polymer nanoparticles with controlled dimensions from the morphological transformation of isotropic seeds.

Understanding and controlling self-assembly processes at multiple length scales is vital if we are to design and create advanced materials. In particular, our ability to organise matter on the nanoscale has advanced considerably, but still lags far behind our skill in manipulating individual molecules. New tools allowing controlled nanoscale assembly are sorely needed, as well as the physical understanding of how they work.

Television and Magazine Alcohol Advertising: Exposure and Trends by Sex and Age.

Objective: The purpose of this study was to document exposure to alcohol advertising by sex, age, and the level and type of alcohol people consume.

Method: We use unique marketing survey data that link the media individuals consume and advertising appearing in those media. Our sample of 306,451 men and women represents the population age 18 and older living in the 48 contiguous United States between 1996 and 2009.

An Economic Evaluation of Food Safety Education Interventions: Estimates and Critical Data Gaps.

The economic evaluation of food safety interventions is an important tool that practitioners and policy makers use to assess the efficacy of their efforts. These evaluations are built on models that are dependent on accurate estimation of numerous input variables. In many cases, however, there is no data available to determine input values and expert opinion is used to generate estimates.

Reporting More but Moving Less? The Complex Relationship between Acculturation and Physical Activity Among US Adults.

Purpose: To investigate the association between acculturation and physical activity (PA).

Design: Cross sectional.

Setting: The National Health and Nutrition Examination Surveys (NHANES) 2003 to 2006.

Reversibly Manipulating the Surface Chemistry of Polymeric Nanostructures via a "Grafting To" Approach Mediated by Nucleobase Interactions.

"Grafting to" polymeric nanostructures or surfaces is a simple and versatile approach to achieve functionalization. Herein, we describe the formation of mixed polymer-grafted nanoparticles through a supramolecular "grafting to" method that exploits multiple hydrogen-bonding interactions between the thymine (T)-containing cores of preformed micelles and the complementary nucleobase adenine (A) of added diblock copolymers. To demonstrate this new "grafting to" approach, mixed-corona polymeric nanoparticles with different sizes were prepared by the addition of a series of complementary diblock copolymers containing thermoresponsive poly(-isopropylacrylamide) (PNIPAM) to a preformed micelle with a different coronal forming block, poly(4-acryloylmorpholine) (PNAM).

Reorganization of hydrogen bond network makes strong polyelectrolyte brushes pH-responsive.

Weak polyelectrolytes have found extensive practical applications owing to their rich pH-responsive properties. In contrast, strong polyelectrolytes have long been regarded as pH-insensitive based on the well-established fact that the average degree of charging of strong polyelectrolyte chains is independent of pH. The possible applications of strong polyelectrolytes in smart materials have, thus, been severely limited.