Anti-biofouling Activity Research Articles

Atomistic Simulations of Hydration and Antibiofouling Behavior of Amphiphilic Polymer Brush Surfaces Functionalized with TMAO and Short Fluorocarbon.

Developing fouling-resistant materials is of paramount interest in marine industries and biomedical applications. In this work, we studied the interfacial hydration and surface-protein interactions of the amphiphilic brush surface functionalized with hybrid hydrophilic trimethylamine N-oxide (TMAO) and hydrophobic pentafluoroethyl groups using a combination of atomistic molecular dynamics simulations and free-energy computations. Our results show that while the interfacial hydration density of the amphiphilic surface slightly decreases with the introduction of small fluorocarbons compared to that of the pure TMAO-functionalized surface, the amphiphilic surface remains relatively strong in resisting protein adsorption. The nanosized clustering of hydrophobic fluorine atoms on the top of the amphiphilic brush surface introduces weak protein adsorption; however, due to the strong interfacial hydration and weak hydrophobic interaction, the amphiphilic surface exhibits sufficient antibiofouling activities. Our fundamental studies will be critical for the discovery of marine fouling-resistant coating surfaces.

Fabrication of metal-organic frameworks containing Cu2+ coated medical PVC catheters with durable antiplatelet and antibacterial activities

Polyvinyl chloride (PVC) catheters are widely used in medical environments especially in blood-contacting devices. In this study, a copper containing MOF material was coated on a PVC catheter to endow it with antiplatelet adhesion and antibacterial activity for potential clinical applications. The immobilization of the coordination polymer containing Cu2+ (Cu-MOF) on the inner surface of PVC catheters was carried out using a bioinspired coating combined with a layer-by-layer self-assembly strategy. Characterization of the Cu-MOF modified surfaces was confirmed using micro-infrared spectroscopy (MIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and water contact angle measurements (WCA). The resultant modified surfaces significantly reduced non-specific adsorption to model proteins with excellent anti-biofouling activity, as well as significantly inhibited the platelet adhesion and activation with superior antiplatelet activity. In vitro whole blood circulation test using a peristaltic pump also showed good antithrombotic properties. Besides, the Cu-MOF modified surfaces exhibited good hemocompatibility (hemolysis ratio < 5 %) and excellent antibacterial activity (approximately 97 % against S. auerus and E. coli). This study develops a simple and effective method for the surface modification of medical PVC catheter as potential blood-contacting biomaterials.

Effects of flow-induced electromagnetic field and surface roughness on antifouling activity of phenolic compounds

Microbial fouling involves the physicochemical interactions between microorganisms and solid surfaces. An electromagnetic field (EMF) may change the diffusion rates of microbial cells and the electrical double layer around the cells and contacting surfaces. In the current study, polycardanol exhibiting antibiofouling activity was modified with ferromagnetic iron oxide (IO) to investigate the EMF effects on bacterial adhesion. When there was a flow of electrolyte that contained bacterial cells, flow-induced EMF was generated according to Faraday’s principle. It was observed that the IO-ionic solution (IS)-modified surfaces, with an induced current of 44, 53, 66 nA, showed decreases in the adhesion of bacteria cells more than the unmodified (polycardanol) and IO-nanoparticles-modified ones. In addition to the EMF effects, the nano-scale uniform roughness of the modified surfaces appeared to play an important role in the reduction of cell adhesion. The results demonstrated that the IOIS-modified surface (3.2 × 10−6 mM IO) had the highest antibiofouling activity.

Halogenated Cyclic Monoterpenoids with Anti-Biofouling Activity from the Okinawan Red Marine Algae Portieria Hornemannii.

The red algal genus Portieria is a prolific producer of halogenated monoterpenoids. In this study, we isolated and characterised monoterpenoids from the Okinawan red algae Portieria hornemannii. A new polyhalogenated cyclic monoterpenoid, 2(R)-chloro-1,6(S)-dibromo-3(8)(Z)-ochtoden-4(R)-ol (1), along with three known monoterpenoids, (2R,3(8)E,4S,6R)-6-bromo-2-chloro-1,4-oxido-3(8)-ochtodene (2), 1-bromo-2-chloroochtoda-3(8),5-dien-4-one (3), and 2-chloro-1-hydroxyochtoda-3(8),5-dien-4-one (4) were isolated from the methanol extract of three populations of P. hornemannii. These compounds were characterised using a combination of spectroscopic methods and chemical synthesis, and the absolute stereochemistry of compounds 1 and 2 was determined. In addition, all isolated compounds were screened for their anti-biofouling activity against the mussel Mytilus galloprovincialis, and 1 exhibited strong activity. Therefore, halogenated monoterpenoids have the potential to be used as natural anti-biofouling drugs.

Antibacterial and Antibiofouling Activities of Carbon Polymerized Dots/Polyurethane and C60/Polyurethane Composite Films.

The cost of treatment of antibiotic-resistant pathogens is on the level of tens of billions of dollars at the moment. It is of special interest to reduce or solve this problem using antimicrobial coatings, especially in hospitals or other healthcare facilities. The bacteria can transfer from medical staff or contaminated surfaces to patients. In this paper, we focused our attention on the antibacterial and antibiofouling activities of two types of photodynamic polyurethane composite films doped with carbon polymerized dots (CPDs) and fullerene C60. Detailed atomic force, electrostatic force and viscoelastic microscopy revealed topology, nanoelectrical and nanomechanical properties of used fillers and composites. A relationship between the electronic structure of the nanocarbon fillers and the antibacterial and antibiofouling activities of the composites was established. Thorough spectroscopic analysis of reactive oxygen species (ROS) generation was conducted for both composite films, and it was found that both of them were potent antibacterial agents against nosocomial bacteria (Klebsiela pneumoniae, Proteus mirabilis, Salmonela enterica, Enterococcus faecalis, Enterococcus epidermis and Pseudomonas aeruginosa). Antibiofouling testing of composite films indicated that the CPDs/PU composite films eradicated almost completely the biofilms of Pseudomonas aeruginosa and Staphylococcus aureus and about 50% of Escherichia coli biofilms.

Construction of oxime-functionalized PCN-222 based on the directed molecular structure design for recovering uranium from wastewater.

The directed construction of productive adsorbents is essential to avoid damaging human health from the harmful radioactive and toxic U(VI)-containing wastewater. Herein, a sort of Zr-based metal organic framework (MOF) called PCN-222 was synthesized and oxime functionalized based on directed molecular structure design to synthesize an efficient adsorbent with antimicrobial activity, named PCN-222-OM, for recovering U(VI) from wastewater. PCN-222-OM unfolded splendid adsorption capacity (403.4 mg·g-1) at pH = 6.0 because of abundant holey structure and mighty chelation for oxime groups with U(VI) ions. PCN-222-OM also exhibited outstanding selectivity and reusability during the adsorption. The XPS spectra authenticated the -NH and oxime groups which revealed a momentous function. Concurrently, PCN-222-OM also possessed good antimicrobial activity, antibiofouling activity, and environmental safety; adequately decreased detrimental repercussions about bacteria and Halamphora on adsorption capacity; and met non-toxic and non-hazardous requirements for the application. The splendid antimicrobial activity and antibiofouling activity perhaps arose from the Zr6(μ3-O)4(μ3-OH)4(H2O)4(OH)4 clusters and rich functional groups within PCN-222-OM. Originally proposed PCN-222-OM was one potentially propitious material to recover U(VI) in wastewater on account of outstanding adsorption capacity, antimicrobial activity, antibiofouling activity, and environmental safety, meanwhile providing a newfangled conception on the construction of peculiar efficient adsorbent.

Eco-infused interfacial enhancement of the anti-biofouling activity in anion exchange membranes for electrodialysis desalination

Strengthened surface modification via bio-safety and eco-friendly agent requirements, and the development of the antibacterial anion exchange membrane (AEM) has become crucial for resource recovery with water-sustainable management to effectively mitigate bacteria-related fouling control. A synergistic antibacterial system of lysozyme and tetrakis(hydroxymethyl)phosphonium sulfate (THPS) is explored here that is immobilized onto the surface of commercial AEM with L-dopa. Compared to the single biomacromolecule lysozyme, THPS performs a vital role in this functional layer by compensating for the insensitivity of the lysozyme to typical Gram-negative bacteria (Such as E. coli). This system demonstrated excellent antibacterial performance (E. coli and S. aureus were selected as test strains) according to the “contact-sterilization”, and the change with contact time was systematically investigated. Based on confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) examination of live and dead bacteria, it was showed that the as-modified membranes by synergistic antibacterial mechanism revealed effective inhibition of biofilm growth. Moreover, these modified layers demonstrated high stability in electrodialysis (ED) desalination systems. The bio-friendly and robust anti-biofouling characteristics of this approach offer valuable insights for constructing antibacterial surfaces in similar applications.

Poly(vinylidene fluoride) ultrafiltration membranes tailored with zirconium‐based MOF‐801 for water treatment applications

AbstractHighly hydrophilic and antifouling poly(vinylidene fluoride) (PVDF) ultrafiltration membranes are developed with excellent permeation using a zirconium‐based metal–organic framework (MOF‐801). MOF‐801 is synthesized by a solvothermal method using zirconium(IV) oxychloride octahydrate (ZrOCl2⋅8H2O) and fumaric acid. The chemical functionality of MOF‐801 is studied by Fourier transform infrared (FTIR) spectroscopy and X‐ray diffraction (XRD) whereas surface morphology and elemental composition are probed by scanning electron microscopy (SEM)/energy‐dispersive X‐ray analysis (EDX). The PVDF/MOF‐801 membranes are characterized in terms of FTIR, XRD, FESEM/EDX and atomic force microscopy. The performance of the hybrid PVDF/MOF‐801 membranes in terms of pure water flux and antifouling ability is found to be improved compared with bare PVDF membranes. The wettability of the membranes is measured by water contact angle and found to be 76.7° for bare PVDF membrane, which decreases upon the addition of MOF‐801 to 55.1° due to the increase in surface hydrophilicity. A notable increase in roughness of 226.29 nm and a porosity of 67.91% is observed for the addition of 2 wt% MOF‐801 in PVDF membrane matrix. The flux recovery ratio of the hybrid membrane is increased from 66.4% to 89.6% and from 68.3% to 85.2% for bovine serum albumin (BSA) and humic acid (HA) separation, respectively. In addition, the reversible and irreversible fouling performance during the rejection of BSA (93%) and HA (88%) indicates the enhanced antifouling property of the PVDF/MOF‐801 membranes. A zone of inhibition test evidences the outstanding antibiofouling activity of the PVDF/MOF‐801 membranes against E. coli and S. aureus. Overall results demonstrated the suitability of hybrid PVDF/MOF‐801 membranes for water and wastewater treatment. © 2023 Society of Industrial Chemistry.

Micro structured Ti- scaffold decorated with Tantalum based amphiphilic assembly for improved biocompatibility, corrosion resistance and bactericidal characteristics

Fouling of body implants is inevitable as they stay in contact with body fluid of harsh ionic composition with varying pH, mixed with serum proteins and bacteria. Some alloys used as implant material comes with inherent bacterial resistant character or in other case the use of antibacterial coating is a popular measure to check the biofouling of their surfaces. But the development of bacterial resistant coating which don’t compromise the cytocompatibility of implant is still a challenging task. In this research, a novel antibacterial metallosurfactant bishexadecyltrimethylammoniumtantalum heptachloride (TaC) is synthesized to coat Ti-6Al-4V surface which provides excellent replacement to pure Tantalum which is a highly demanded implant material. For this, Ti-6Al-4V surface was acid treated to grow microstructures and porosity to help covalent bonding with TaC molecules and get durable and robust coating. The TaC coating was characterized as highly stable, hydrophilic, bioactive (assist osseointegration), antimicrobial against Gram negative (E. coli) and Gram positive (S. aureus), anti- corrosive in abiotic as well as biotic medium and compatible with fibroblast tissues. Being amphiphilic in nature, the coating interferes with serum albumin (BSA) adsorption on Ti-6Al-4V surface. Retardation in BSA adsorption due to TaC coating is evident from contact angle, XPS and electro chemical studies. The key appeal of coating is its simple fabrication technique and cost-effectiveness, moreover its chemical and structural features is such that it promotes fibroblast adhesion and viability. The coating exhibited a perfect balance to cater the antibiofouling activity and fibroblast proliferation which is biggest challenge in fabrication of biomaterials. Various results obtained from this comprehensive study may advocate the clinical applications of Ta metallosurfactant coating on biomedical alloys.

Engineering layered double hydroxide with enzyme-mimicking antibiofouling ability for uranium capture

Materials capable of capturing environmentally mobile uranium from various sources, including nuclear waste and bio-aggressive seawater, are critical for energy and environmental sustainability. Unfortunately, the stability and reusability of existing absorbents is limited in seawater due to the ubiquitous and notorious biofouling, and therefore, developing high-performance materials with antibiofouling activity is of great importance for uranium capture. Here we report a tungstate exchanged layered double hydroxide composite (MgAl-LDH-NO3--WO42-) that exhibits a significant uranium removal efficiency of 98.8 % in 240 ppm uranium-containing wastewater and a maximum uptake capacity of 409.6 mg g−1. More importantly, MgAl-LDH-NO3--WO42- displays an excellent antibiofouling ability in bio-aggressive seawater by mimicking natural haloperoxidase in marine algae, enabling the excellent cyclic stability for uranium capture from seawater. This work provides an effective strategy to develop highly efficient LDH-based materials for uranium capture.

Inhibition of biofilm formation and settlement of barnacle larvae by a biosurfactant produced from a marine biofilm-forming Exiguobacterium sp. R58

Natural product based antifouling strategies are promising alternatives for achieving biofouling control with minimal environmental burden. Although microbial biosurfactants have shown antimicrobial and antibiofilm activities, their efficacy on settlement of barnacles, among the most problematic of biofouling organisms in the marine environment, has not be evaluated. Biofilm-forming bacteria isolated from the seawater cooling system of a power plant were screened for biosurfactant production and one of the promising strains was identified as Exiguobacterium sp. R58. Production, characterization and anti-biofouling activity of the biosurfactant was determined. Emulsifying activity of 68–89% was achieved at 4−100 °C, 2–12% salinity and 2–12 pH. Biofilm formation by Escherichia coli, Staphylococcus aureus, Salinococcus sp., and Marinobacter sp. was strongly inhibited (80–92%) in the presence of 2000 μg/mL biosurfactant. Cypris larval settlement was impaired by the biosurfactant without causing mortality. Biosurfactant coated surfaces prevented biofilm formation and cypris settlement. Adhesion of bacteria on biosurfactant coated surfaces was 75–93% lower as compared to control. Cypris settlement was inhibited completely in Petri dishes coated with 5.6–22.7 mg/cm2 in no-choice assays and 1.3 mg/cm2 in choice assays. Antibiofouling activity of the biosurfactant was related to surface modification, thus promising for developing non-toxic antifouling materials.

Polydopamine functionalised ceria-zirconia nanoparticles embedded water-borne epoxy nanocomposite for anti-biofouling coatings

Biofouling, the accumulation of microorganisms, plants, algae on wet surfaces is one of the major issues adversely affecting the overall hydrodynamic performance of the marine vessels. Ceria (CeO2) nanoparticles (NPs) are effectively used as anti-biofouling agent to prevent the deterioration of steel structures, due to their excellent redox capacity. Various approaches are being investigated to enhance the antifouling activity of ceria NPs. Here, we report the development of novel polydopamine (PDA) functionalised ceria-zirconia nanoparticles filled water-borne epoxy nanocomposite coating to prevent the microbial-induced corrosion of mild steel. Ceria NPs were functionalised with PDA to enhance the dispersibility and improve their ability to resist biofouling in water-borne epoxy resin coatings against microbial species. As the anti-biofouling activity of ceria depends on their oxygen storage capacity, zirconium was incorporated to create a defective crystal structure with more active oxygen storage and release sites. Ceria and ceria-zirconia NPs were synthesised by precipitation method and functionalised with PDA. The functionalisation of ceria-zirconia (CZ) NPs was confirmed by Fourier Transform Infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), Confocal Raman spectroscopy and X-ray Photon spectroscopy (XPS). Thermogravimetric analysis (TGA) shows that incorporation of zirconium increases the amount of oxygen vacancies in the crystal lattice there by enhancing ceria's redox potential. Anti-biofouling and anti-biocorrosion properties of the coatings were explored against different microbial strains. The antibacterial tests show that colony-forming units (CFU) of PDA functionalized ceria-zirconia epoxy (EPCZ) nanocomposites were suppressed by 93 % and 87 % in the case of Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) bacteria, respectively. Biofilm inhibition studies show that EPCZ nanocomposite coatings have higher biofilm inhibition efficiency against gram-negative bacteria (96.37 %) than gram-positive bacteria (62.67 %) due to the differences in their morphology. The practical applicability of the nanocomposite coatings was studied using cultured seawater consortia, and the results reveal that PCZ nanoparticles provide superior biofilm inhibition. Electrochemical impedance spectroscopy (EIS) reveals that the EPCZ coatings exhibit significant enhancement in charge transfer resistance and coating resistance. The synergistic effect of PDA functionalisation and zirconium incorporation in ceria leads to the exceptional biocorrosion resistance in corrosive bacterial environments.

Synthesis of a novel microplastic trap with abundant oxime groups based on MOF-545 post-engineering for the environmental pollution control and water remediation

The elimination of microplastics (MPs) from aquatic systems is a great challenge because of its miniature dimension and exorbitant stability. Hence, a novel MP trap with abundant oxime groups (MOF-545-oxime) was triumphantly synthesized based on MOF-545 post-engineering. The supreme MP adsorption capacity of MOF-545-oxime was 294.6 mg/g, which also manifested excellent selectivity and reusability for MP adsorption. Moreover, the kinetic, isothermal and thermodynamic models were used to inquiry the MP adsorption mechanism, which was governed by electrostatic attraction, coordination, and π–π interactions. The XPS spectra and adsorption energy calculations upheld the CN–OH and CN groups executed a pivotal part in the MP adsorption process of MOF-545-oxime. MOF-545-oxime also possessed splendid anti-biofouling activity and environmental safety, which efficaciously diminished the pessimistic influences of Halamphora upon the MP adsorption capacity and complied with the requirements for non-toxicity and innocuousness in the adsorbent application. The superb anti-biofouling activity and environmental safety of MOF-545-oxime might be due to the abundant functional groups and stable chemical structure. Indubitably, the development of efficacious adsorbents is crucial for the MP removal from aquatic systems. The originally proposed MOF-545-oxime has a great potential to remove MPs from aquatic systems, which also offers an inspiration for perfect high-efficiency adsorbents.

Antibiofouling activity of 1-hexadecyl-3-methylimidazolium chloride against Amphora sp. BARC 104, a fouling diatom isolated from back waters of Kalpakkam

1-Hexadecyl-3-methylimidazolium chloride (C16MimCl), an alkylimidazolium ionic liquid (IL) with a long alkyl side chain (-hexadecyl group) is attractive for antimicrobial applications. However, there are limited studies on the antifouling efficacy of ILs using biofouling organisms especially diatoms. In this study, the antifouling activity of C16MimCl was determined against Amphora sp. BARC 104, a dominant fouling diatom isolated from Kalpakkam coastal waters. Growth of the diatom was inhibited in the presence of IL at varied concentrations starting from 0.15 μM C16MimCl. A complete inhibition in the growth was observed in the presence of 2.5 μM C16MimCl. Adhesion and biofilm formation by Amphora sp. was strongly inhibited at sub-micromolar concentrations of IL. Exposure of diatom cells to IL in acute toxicity assays induced oxidative stress (increased reactive oxygen species generation) and reduced metabolic activity (decreased esterase activity) as revealed by 2,7 -Dichlorodihydrofluorescein diacetate (DCH2FDA) and fluorescein diacetate (FDA) staining, respectively. SYTOX® Green staining and extracellular chlorophyll a measurement revealed a severe membrane damage and leakage of chlorophyll a, respectively, in IL treated diatom cells. These measurements during recovery experiments indicated a permanent damage to cell and thylakoid membranes in the diatom cells. Damage to multiple cellular targets coupled with strong antibiofilm activity suggest potential application of C16MimCl in preparation of antifouling formulations and coatings.

Ion-imprinted nanocellulose aerogel with comprehensive optimized performance for uranium extraction from seawater

Significantly abundant uranium resources in seawater are considered promising alternatives to terrestrial uranium reserves. The adsorption capacity and speed, binding selectivity, mechanical properties, and antibiofouling ability are the most important features for practical uranium adsorbent applications. Herein, a new nanocellulose aerogel, which contains specific binding spatial structures for uranyl ions, designated as I-CNF aerogel, is fabricated by combining ion-imprinting and chemical cross-linking strategies. The ion-imprinted and chemically stabilized functional sites endow the I-CNF aerogel with robust binding affinity and selectivity for uranyl ions. The ordered lamellar structure, porosity, and high hydrophilicity together facilitate uranyl ion access to the functional sites in the adsorbent and endow the adsorbent with a high uranium adsorption capacity. Furthermore, owing to the chemical cross-linking process and the generated Schiff base groups, the adsorbent exhibits high mechanical strength, excellent reusability, and effective antibiofouling activity. Benefitting from these optimized properties, I-CNF aerogel demonstrates a high uranium extraction capacity of 9.46 mg g−1 with an ultrahigh selectivity of 19.01 to uranium against vanadium in natural seawater, making it a highly potential candidate for practical uranium extraction in natural seawater.

Novel Triple Stimuli Responsive Interpenetrating Poly(Carboxybetaine Methacrylate)/Poly(Sulfobetaine Methacrylate) Network

The study reports the synthesis and characterization of novel triple stimuli responsive interpenetrating polymer network (IPN) based on two polyzwitterionic networks, namely of poly(carboxybetaine methacrylate) and poly(sulfobetaine methacrylate). The zwitterionic IPN hydrogel demonstrates the ability to expand or shrink in response to changes in three "biological" external stimuli such as temperature, pH, and salt concentration. The IPN hydrogel shows good mechanical stability. In addition, other important features such as non-cytotoxicity and antibiofouling activity against three widespread bacteria as P. Aeruginosa, A. Baumanii, and K. Pneumoniae are demonstrated. The in vivo behavior of the novel zwitterionic IPN hydrogel suggests that this smart material has very good potential as a biomaterial.

Corrosion resistance of Cu-Zr(O) N films in a simulated seawater environment

Corrosion and antibiofouling protection of maritime transport are important to improve lifetime usage and reduce maintenance costs. Tributyltin (TBT) paint was the most widely used solution, but it was banned due to environmental toxicity in 2008. Multifunctional coatings can be the solution for many current issues, particularly in situations where it is necessary to combine dissimilar properties such as anticorrosion and antibacterial. Zirconium (oxy)nitrides (coatings with great corrosion resistance) doped with copper (proved already to show antibiofouling activity) were obtained by unbalanced magnetron sputtering with a reactive atmosphere to add the anticipated multifunctional characteristics. The properties of obtained films were assessed by SEM, EDS, XRD, AFM, and contact angle measurements. EIS and potentiodynamic polarization tests were performed in NaCl (3.5 % wt.) solution for 168 h to simulate seawater exposure. The results demonstrated that Cu did not form, with Zr(O)N, a crystalline phase. Moreover, Cu incorporation promotes voids among column boundaries of ZrON films, directly influencing their roughness, surface energy, porosity index, and wettability. Regarding corrosion resistance, the inclusion of Cu worsens the Zr(O)N chemical stability against seawater. The obtained results demonstrated the incapability of Cu-Zr(O)N films to be applied as unique coatings to avoid biofouling under seawater exposure due to copper addition.

Highly efficient antibacterial adsorbent for recovering uranium from seawater based on molecular structure design of PCN-222 post-engineering

Herein, a novel amidoxime functionalized metal organic framework (MOF)-based adsorbent named PCN-222-AO was obtained by grafting amidoxime groups on the surface of PCN-222 through amination, cyanylation and amidoximation modification reactions successively. The PCN-222-AO exhibited outstanding adsorption capacity (432.7 mg·g−1), selectivity and reusability in U(VI) adsorption at pH = 7.0, and showed superb adsorption performances in the simulated and real seawater. The XPS spectra and adsorption energy calculations confirmed the CN (H2TCPP), C=N-OH and -NH(2) groups served a vital role in the U(VI) adsorption process. PCN-222-AO illustrated excellent antibacterial property, anti-biofouling activity and environmental safety, which effectively reduced the negative impacts of bacteria (E. coli and S. aureus) and Halamphora upon the U(VI) adsorption capacity and complied with the requirements for non-toxicity and innocuousness in the adsorbent application. The excellent antibacterial property and anti-biofouling activity may be attributed to Zr6 cluster and abundant functional groups in the PCN-222-AO. Undoubtedly, the molecular structure design and construction of effective adsorbents are crucial for the U(VI) resource recovery. As first reported in this study, PCN-222-AO is a promising adsorbent to recover U(VI) from seawater, providing a new idea about the molecular structure design and construction of novel high-efficiency adsorbent.

Zwitterionic Polymers Coating Antibiofouling Photoelectrochemical Aptasensor for In Vivo Antibiotic Metabolism Monitoring and Tracking.

Long-term in vivo monitoring and tracking of target molecules in living organism is essential to reveal vital physiological activity. However, undesirable contamination of protein and biological cells may bring serious biofouling issues. Herein, zwitterionic sulfobetaine methacrylate (SBMA) polymers are grafted on the TiO2 nanotube (NT) surface with polydopamine (PDA) as linker to fabricate a TiO2 NTs/PDA/SBMA photoelectrode. The TiO2 NTs/PDA/SBMA/aptamer-based PEC aptasensor can be sensitive and have selective detection of target molecules with excellent antibiofouling activity. Beneficial from the above advantages, the implantable micro-PEC aptasensor has implemented in vivo tracking and monitoring of the metabolism of antibiotics in a living mouse. The robust antibiofouling property generates new inquiries and an approach for long-standing questions in a new way for reliable and long-term sensing of vital biomolecules in complex biological fluids and uncovers a promising advance of intrinsic physiological mechanisms.

Fabrication and Characterization of Zwitterionic Coatings with Anti-oil and Anti-biofouling Activities

Underwater ultraoleophobic materials with superhydrophilic surfaces have great potential for several applications due to their anti-fouling, self-cleaning, oil/water separation, droplet manipulation, and drag reduction properties. In our research described here an underwater ultraoleophobic coating containing zwitterion carboxybetaine acrylamide (CBAA) was prepared using self-polymerization of dopamine (DA) and co-deposition of polydopamine (PDA) with zwitterionic poly(carboxybetaine acrylamide) (PCBAA) based on hydroxyl radical activation. The morphology of the coatings could be easily controlled by adjusting the initial ratio of dopamine/carboxybetaine acrylamide (DA/CBAA). The structures, surface morphologies and properties of the coatings so obtained were analyzed by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), atomic force microscopy (AFM) and contact angle measurements. The polydopamine/poly(carboxybetaine acrylamide) (PDA/PCBAA) coatings exhibited excellent superhydrophilicity and underwater superoleophobicity with water contact angles (WCA) of 1.5° and underwater oleophobicity contact angles (OCA) of 160°. The anti-biofouling, oil-water separation, and mechanical stability properties for PDA/PCBAA co-deposited coating were comprehensively investigated. These interesting properties make the coatings promising candidates for numerous applications.