Rationale Design for Anchoring Pendant Groups of Zwitterionic Polymeric Medical Coatings.

A biocompatible and antifouling polymeric medical coating was developed through rational design for anchoring pendant groups for the modification of stainless steel. Zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) was copolymerized individually with three anchoring monomers of carboxyl acrylamides with different alkyl spacers, including acryloylglycine (2-AE), 6-acrylamidohexanoic acid (6-AH), and 11-acrylamidoundecanoic acid (11-AU). The carboxylic acid groups are responsible for the stable grafting of copolymers onto stainless steel via a coordinative interaction with metal oxides.

Impacts of different slash disposals on soil and water erosion of high-intensity management Eucalyptus grandis × urophylla plantation.

Background: The slash disposal-burning forest-in high-intensity management Eucalyptus grandis × urophylla plantation has accelerated soil degradation.

Statement Of The Problem: Slash disposals is a contributing factor, but its specific role in the correlation between rainfall-runoff and soil erosion remains elusive.

Objectives: his study investigated the characteristics of rainfall-runoff and soil erosion resistance in different methods of slash disposals in plantation.

A pH-Sensitive Stretchable Zwitterionic Hydrogel with Bipolar Thermoelectricity.

Amid growing interest in using body heat for electricity in wearables, creating stretchable devices poses a major challenge. Herein, a hydrogel composed of two core constituents, namely the negatively-charged 2-acrylamido-2-methylpropanesulfonic acid and the zwitterionic (ZI) sulfobetaine acrylamide, is engineered into a double-network hydrogel. This results in a significant enhancement in mechanical properties, with tensile stress and strain of up to 470.

Soil qualities and change rules of Eucalyptus grandis × Eucalyptus urophylla plantation with different slash disposals.

Slash disposal changes soil quality by affecting soil properties and nutrient cycling, and the appropriate disposal approaches remain controversial. This work aimed to explore the impact of different slash disposal methods on soil qualities. For this purpose, a Eucalyptus grandis × Eucalyptus urophylla plantation that had been cultivated in 2002 and felled for the third time in 2016 was established in Hezhou City, China.

Potential effects of soil chemical and biological properties on wood volume in Eucalyptus urophylla × Eucalyptus grandis hybrid plantations and their responses to different intensity applications of inorganic fertilizer.

Long-term and high-intensity application of inorganic fertilizer leads to a strong variation of soil characteristics. The changes in soil chemical and biological properties can significantly affect the yield of Eucalyptus plantation. However, the mechanism of soil chemical properties affecting wood volume mediated by biological factors is not clear.

Bio-inspired zwitterionic polymeric chelating assembly for treatment of copper-induced cytotoxicity and hemolysis.

We developed a hemocompatible, bio-inspired, multivalent, polymeric-chelating assembly based on the poly(2-methacryloyloxyethyl phosphorylcholine)-b-poly(serinyl acrylate) (PMPC-b-PserA) zwitterionic diblock copolymer. Functional PMPC-b-PserA was synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization to catch and encapsulate free copper ions (Cu) in a solution. PMPC with an identical polar group to phospholipids exhibits high hydrophilicity and fouling resistance against non-specific adsorption, and inertness to the metal ions.

Complete zwitterionic double network hydrogels with great toughness and resistance against foreign body reaction and thrombus.

Conventional tough hydrogels offer enhanced mechanical properties for load-bearing implants; however, their application is still hindered by a lack of biocompatibility. In this study, we demonstrate a new methodology for developing biocompatible double network (DN) hydrogels by using a responsive amphoteric polymer as a first framework. Tough DN hydrogels were formed by penetrating zwitterionic poly(sulfobetaine acrylamide) (PSBAA) into a swollen poly(lysine acrylamide) (PLysAA) network in an acidic or alkaline solution, and polymerizing under UV irradiation.

Polyelectrolyte and Antipolyelectrolyte Effects for Dual Salt-Responsive Interpenetrating Network Hydrogels.

This work presents a salt-responsive interpenetrating network (IPN) hydrogel with effective antimicrobial properties and surface regeneration. The hydrogels were engineered using the double network strategy to form loosely cross-linked zwitterionic poly(sulfobetaine vinylimidazole) (pSBVI) networks into the highly cross-linked cationic poly((trimethylamino)ethyl methacrylate chloride) (pTMAEMA) framework via photopolymerization. The pTMAEMA/pSBVI hydrogel has strong mechanical properties, with a fracture stress 120× higher than single network pTMAEMA hydrogel.

Non-sticky and antimicrobial zwitterionic nanocomposite dressings for infected chronic wounds.

Zwitterionic poly(sulfobetaine acrylamide) (pSBAA)-based nanocomposite hydrogels impregnated with germicidal silver nanoparticles (AgNPs) were synthesized and implemented for the treatment of infected chronic wounds. The zwitterionic hydrogels exhibited excellent non-sticky properties and had reinforced mechanical properties by the addition of hectorite nanoclay and poly(ethylene glycol)dimethacrylate as physical and chemical crosslinkers, respectively. In addition, AgNPs were grown within the intercalated clay/polymer structure by in situ free radical reduction, as confirmed by UV-vis spectroscopy and transmission electron microscopy (TEM).

Zwitterionic nanocomposite hydrogels as effective wound dressings.

In this study, zwitterionic poly(sulfobetaine acrylamide) (pSBAA) nanocomposite hydrogels were synthesized and implemented as effective chronic wound dressings. The hydrogels exhibited reinforced mechanical properties from added hectorite nanoclay as a physical crosslinker in the polymer chains. Due to the strong interaction with water molecules via ionic solvation, the hydration of the zwitterionic nanocomposite hydrogels was superior to the non-ionic 2-hydroxyethyl methacrylate (pHEMA) hydrogels, which interacts with water molecules via hydrogen bonding.

Surface Modification for Superhydrophilicity and Underwater Superoleophobicity: Applications in Antifog, Underwater Self-Cleaning, and Oil-Water Separation.

A facile yet effective surface modification strategy for superhydrophilicity and underwater superoleophobicity was developed by silanization of zwitterionic sulfobetaine silane (SBSi) on oxidized surfaces. The coatings exhibit excellent wetting properties, as indicated by static contact angles of <5°, and long-term stability under exposure to heat and UV irradiation. The SBSi-modified surfaces were employed for applications in antifog, self-cleaning, and oil-water separation.