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1.
J Colloid Interface Sci ; 677(Pt B): 583-596, 2025 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-39154450

RESUMEN

HYPOTHESIS: An innovative strategy for designing high-performance demulsifiers is proposed. It hypothesizes that integrating mesoscopic molecular simulations with macroscopic physicochemical experiments can enhance the understanding and effectiveness of demulsifiers. Specifically, it is suggested that amphiphilic hyperbranched polyethyleneimine (CHPEI) could act as an efficient demulsifier in oil-water systems, with its performance influenced by its adsorption behaviors at the oil-water interface and its ability to disrupt asphaltene-resin aggregates. EXPERIMENTS: Several coarse-grained models of oil-water systems, with CHPEI, are constructed using dissipative particle dynamics (DPD) simulation. Following the insights gained from the simulations, a series of CHPEI-based demulsifiers are designed and synthesized. Demulsification experiments are conducted on both simulated and crude oil emulsions, with the process monitored using laser scanning confocal microscopy. Additionally, adsorption kinetics and small angle X-ray scattering are employed to reveal the inherent structural characteristics of CHPEI demulsifiers. FINDINGS: CHPEI demonstrates over 96.7 % demulsification efficiency in high acid-alkali-salt systems and maintains its performance even after multiple reuse cycles. The simulations and macroscopic experiments collectively elucidate that the effectiveness of a demulsifier is largely dependent on its molecular weight and the balance of hydrophilic and hydrophobic groups. These factors are crucial in providing sufficient interfacial active functional groups while avoiding adsorption sites for other surfactants. Collaborative efforts between DPD simulation and macroscopic measurements deepen the understanding of how demulsifiers can improve oil-water separation efficiency in emulsion treatment.

2.
Adv Mater ; : e2411700, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39363692

RESUMEN

Organogel materials are vital for impact or shock resistance because of their highly tailored dynamic properties. However, concurrently achieving excellent anti-impact and damping performances, high stability, and self-healing properties is challenging. Herein, a novel intelligent protective organogel (IPO) comprising a dynamic boronic ester containing poly(urethane-urea) as the network skeleton with a matching mesh size is synthesized, the network precisely entraps the hyperbranched fluid used as the bulky solvent via steric hindrance. The IPO exhibits self-healing ability, excellent impact responsiveness (a 1950-fold increase in flow stress under various impact speeds), and energy dissipation (the loss factor >0.8 from 10-4  to 104 Hz). The IPO maintains its dynamic mechanical properties during hot pressing and hydrolysis, exhibiting  high stability. Furthermore, the IPO exhibits omnibearing protection. When used as a protective coating, the IPO dissipates the impact force by 87% and 89% of control upon passive and active impact, respectively. When used as a shock pad, it attenuates 91% of the amplitude in the high-frequency vibrations. This study offers a novel perspective on the synthesis of tailored sterically hindered organogel and provides valuable insights into the development of next-generation intelligent protective materials that exhibit impact and vibration resistance.

3.
J Hazard Mater ; 480: 136026, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39368361

RESUMEN

Environmental contamination from oil spills and industrial oily wastewater poses significant ecological risks due to the persistence of harmful organic compounds. To address these challenges, magnetic composite nanospheres (CMNP@CHPEI) are systematically developed, with carboxylated Fe3O4 nanoparticles (CMNP) as the core and amphiphilic hyperbranched polyethyleneimine (CHPEI) as the decorated shell. These novel nanospheres combine the controllable size and magnetic responsiveness of "hard" magnetic nanomaterials with the structural complexity and functional diversity of "soft" hyperbranched polymers. This design allows for switching between emulsification and demulsification behaviors by regulating the size of the nanospheres and the amphiphilicity of CHPEI. Specifically, the nanospheres can form Pickering emulsions with oil droplet sizes smaller than 1 µm, maintaining stability for up to 75 days, and achieve rapid oil-water separation with demulsification efficiencies up to 99.8 %. Even after seven recycling experiments, they still retain significant interfacial activity and applicability. Interfacial characteristic experiments and molecular dynamics simulations reveal that particle size directly affects the film structures formed at oil-water interface, while the amphiphilic functional molecules determine the interaction mode of nanospheres with oil-water phases. These achievements introduce a versatile, environmentally friendly material for removing hazardous oil-based pollutants, with promising applications in oil spill remediation and industrial wastewater treatment.

4.
ACS Appl Bio Mater ; 7(10): 6682-6695, 2024 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-39388599

RESUMEN

Synthetic hyperbranched polyesters with potential therapeutic properties were synthesized using the bifunctional polyethylene glycol or PEG with different molecular weights, ca., 4000, 6000, and 20,000 g/mol, and the trifunctional trans-aconitic acid or TAA. During polycondensation, a fixed amount of PEG was allowed to react with varying amounts of TAA (1:1 and 1:3) to control the branching extents. It was found that the synthetic polyesters had a considerable yield and were highly water soluble. Spectroscopic data (Fourier transform infrared and 1H NMR) confirmed the polyester formation; the branching percentages were determined from 1H NMR spectroscopy which varied from 73% to 22% among the synthesized samples. As the molecular weight of PEG was increased, the branching percentage drastically dropped. All polyesters were found to be negatively charged due to the ionization of unreacted -COOH in the branched ends at the working pH (7.4). Both the hydrodynamic size and intrinsic viscosity were found to reduce as the branching extent increased. Among the sets of polyesters, the one with the highest branching percentage (73%) showed the core-shell morphology (evident from field emission scanning electron microscopy and transmission electron microscopy studies). It also exhibited the highest efficiency toward Ca2+ influx in neuronal cells due to the unique morphology and the negatively charged surface. Nevertheless, this particular grade of polyester along with all the other grades was cytocompatible and induced reactive oxygen species generation. Since the maximally branched grade was highly efficient in altering the Ca2+ signaling through stronger influx, it may well be tested for treating neuronal disorders in vivo in future.


Asunto(s)
Materiales Biocompatibles , Ensayo de Materiales , Neuronas , Poliésteres , Poliésteres/química , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Neuronas/metabolismo , Neuronas/citología , Señalización del Calcio , Animales , Tamaño de la Partícula , Supervivencia Celular/efectos de los fármacos , Polietilenglicoles/química , Ratas , Calcio/metabolismo , Calcio/química , Estructura Molecular
5.
ACS Appl Bio Mater ; 2024 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-39475495

RESUMEN

Multidrug-resistant (MDR) Gram-negative bacteria infections have gradually become a more serious health problem recently, and antibacterial drugs are urgently needed to tackle MDR Gram-negative bacteria. Herein, we synthesized a series of quaternary ammonium salt derivatives of hyperbranched polylysine (HPL-Cm-n) with different alkyl chain lengths (m = 4, 8, 12, 16) and grafting ratios (n = 5.8-21.0) of alkyl quaternary ammonium salts (Cm). HPL-Cm-ns exhibited excellent antibacterial activities against drug-sensitive E. coli and P. aeruginosa, and specifically, HPL-C12-ns were also highly active against MDR E. coli and P. aeruginosa. The cytotoxicity and hemolytic activity of HPL-Cm-ns increased with the increase in the alkyl chain length and the grafting ratio of Cm. The killing study proved that HPL-C12-9.5 had fast killing kinetics and was bactericidal toward both drug-sensitive and MDR E. coli. The mechanistic studies showed that, similar to hyperbranched polylysine (HPL), HPL-C12-9.5 killed bacteria by disrupting the cell membranes and causing leakage of the cytoplasmic contents. HPL-C12-ns might have potential as an antibacterial agent to combat MDR Gram-negative bacteria.

6.
Int J Biol Macromol ; 281(Pt 4): 136435, 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39414191

RESUMEN

Cellulose nanocrystals (CNCs), derived from diverse sources and distinguished by their inherent biodegradability, excellent biocompatibility, and facile cellular engulfment due to their rod-like structure, hold great promise as carriers for the development of nano-delivery systems. In this work, highly efficient rod-like CNCs were employed as substrates for grafting glycidyl onto their surfaces through ring-opening polymerization, forming hyperbranched polymers with superior cell uptake properties. Subsequently, 4-vinylbenzeneboronic acid (VB) and poly (ethylene glycol) methyl ether methacrylate (PEGMA) were employed as monomers in the polymerization process to fabricate a pH-responsive targeted nano-delivery system, denoted as CNCs-VB-PEGMA, via single electron transfer reactive radical polymerization (SET-LRP) reaction. The CNCs-VB-PEGMA was successfully prepared and used for the loading of curcumin (Cur) to form a pH-responsive nano-delivery system (CNCs-VB-PEGMA-Cur), and the loading rate of Cur was as high as 70.0 %. Studies showed that this drug delivery system could actively targeting liver cancer cells with the 2D cells model and 3D tumor microsphere model, showing efficient liver cancer cell-killing ability. Collectively, the CNCs-VB-PEGMA drug delivery system has potential applications in liver cancer therapy as an actively targeting and pH-responsive drug delivery system.

7.
Chempluschem ; : e202400454, 2024 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-39307836

RESUMEN

Hyperbranched polyethyleneimine having 25,000 Da molecular weight was functionalized by a simple sulfopropylation reaction, affording a novel N-sulfopropylated PEI derivative (PEI-SO3 -). The successful introduction of N-sulfopropyl and sulfobetaine groups to the amino groups of PEI was spectroscopically confirmed. Furthermore, the antibacterial and anti-cyanobacterial activity of PEI-SO3 - in comparison to the parent PEI were investigated on two type heterotrophic bacteria, i. e., Gram (-) Escherichia coli and Gram (+) Staphylococcus Aureus bacteria, and one type of autotrophic cyanobacterium, i. e. Synechococcus sp. PCC 7942. Both PEI-SO3 - and PEI showed an enhanced, concentration-dependent antibacterial and anti-cyanobacterial activity against the tested bacteria strains, with PEI-SO3 - exhibiting higher activity than the parent PEI, signifying that the introduction of the sulfopropyl and sulfobetaine groups to the PEI amino groups enhanced the antibacterial and the anti-cyanobacterial properties of PEI. In the case of cyanobacteria, PEI-SO3 - was found to affect the integrity of the photosynthetic system by the inhibition of Photosystem-II electron transport activity. Cytocompatibility and hemocompatibility studies revealed that PEI-SO3 - exhibits high biocompatibility, suggesting that PEI-SO3 - could be considered as an attractive antibacterial and anti-cyanobacterial candidate for various applications in the disinfection industry and also against the harmful cyanobacterial blooms.

8.
Chempluschem ; : e202400302, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39230969

RESUMEN

The organic-inorganic hybrid fluorescent hyperbranched polymer, including hyperbranched polysiloxane and hyperbranched polyborate, have attracted much attention due to their excellent optical properties and wide range of applications. Hyperbranched polysiloxane and polyborates, prepared by introducing Si or B elements into organic polymer chains at the molecular level through rational molecular design and novel synthesis methods, exhibit outstanding photophysical properties as an indispensable branch of organic-inorganic hybrid fluorescent materials. Herein, this review highlights the recent research progress on hyperbranched polysiloxanes and hyperbranched polyborates, including strategies for regulating their emission wavelengths, quantum yields, and fluorescence lifetimes, potential emission mechanisms, and various applications. Finally, some challenges and promising future directions in the field of organic-inorganic hybrid fluorescent polymers are summarized.

9.
Acta Biomater ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39222706

RESUMEN

The escalating menace of antimicrobial resistance (AMR) presents a profound global threat to life and assets. However, the incapacity of metal ions/reactive oxygen species (ROS) or the indiscriminate intrinsic interaction of cationic groups to distinguish between bacteria and mammalian cells undermines the essential selectivity required in these nanomaterials for an ideal antimicrobial agent. Hence, we devised and synthesized a range of biocompatible mixed-charge hyperbranched polymer nanoparticles (MCHPNs) incorporating cationic, anionic, and neutral alkyl groups to effectively combat multidrug-resistant bacteria and mitigate AMR. This outcome stemmed from the structural, antibacterial activity, and biocompatibility analysis of seven MCHPNs, among which MCHPN7, with a ratio of cationic groups, anionic groups, and long alkyl chains at 27:59:14, emerged as the lead candidate. Importantly, owing to inherent differences in membrane potential among diverse species, alongside its nano-size (6-15 nm) and high hydrophilicity (Kow = 0.04), MCHPN7 exhibited exceptional selective bactericidal effects over mammalian cells (selectivity index > 564) in vitro and in vivo. By inducing physical membrane disruption, MCHPN7 effectively eradicated antibiotic-resistant bacteria and significantly delayed the emergence of bacterial resistance. Utilized as a coating, MCHPN7 endowed initially inert surfaces with the ability to impede biofilm formation and mitigate infection-related immune responses in mouse models. This research heralds the advent of biocompatible polymer nanoparticles and harbors significant implications in our ongoing combat against AMR. STATEMENT OF SIGNIFICANCE: The escalating prevalence of antimicrobial resistance (AMR) has been acknowledged as one of the most significant threats to global health. Therefore, a series of mixed-charge hyperbranched polymer nanoparticles (MCHPNs) with selective antibacterial action were designed and synthesized. Owing to inherent differences in membrane potential among diverse species and high hydrophilicity (Kow = 0.04), the optimal nanoparticles exhibited exceptional selective bactericidal effects over mammalian cells (selectivity index >564) and significantly delayed the emergence of bacterial resistance. Importantly, they endowed surfaces with the ability to impede biofilm formation and mitigate infection-related immune responses. Furthermore, the above findings focus on addressing the problem of AMR in Post-Pandemic, which will for sure attract attention from both academic and industry research.

10.
Artículo en Inglés | MEDLINE | ID: mdl-39262294

RESUMEN

OBJECTIVES: This study aimed to explore multiple effects of hyperbranched poly-l-lysine (HBPL) titanium (Ti) surfaces on osseointegration, bacteriostasis, and anti-inflammation across three different animal models. METHODS: Ti surfaces were covalently modified with HBPL, with uncoated surfaces as controls. Characterization included scanning electron microscopy (SEM) and surface chemistry and elemental analysis (EDX). Ti and Ti-HBPL implants were placed in conventional canine edentulous sites, post-operative infection canine edentulous sites, and diabetic rat tibias. Implants from canine edentulous models were analyzed using micro-CT and histomorphometry to assess osseointegration at 8 weeks. Post-operative infection beagles were used to evaluate antibacterial efficacy through clinical parameters and bacterial cultures at 1 week. In diabetic rats, micro-CT and histomorphometry were performed at 8 weeks. RESULTS: HBPL was uniformly grafted on Ti-HBPL surfaces. Ti-HBPL surfaces showed higher bone volume/total volume (BV/TV, p < 0.001), bone-implant contact (BIC%, p < 0.001), and trabecular number (Tb.N, p < 0.01) in beagles. Besides, it displayed higher BIC% (p < 0.001) and bone area fraction occupancy (BAFO%, p < 0.01) in hard tissue sections. In an infected model, Ti-HBPL surfaces exhibited lower bleeding on probing (BOP, p < 0.001), and plaque index (DI, p < 0.01), with reduced bacterial colony formation (p < 0.001) compared to the control group. In diabetic rats, Ti-HBPL surfaces showed an increase in BV/TV (p < 0.01) and Tb.N (p < 0.001), downregulated TNF-α and IL-1ß (p < 0.01), and upregulated IL-10 (p < 0.01) and osteocalcin (OCN) expression (p < 0.01). CONCLUSIONS: HBPL-Ti surfaces demonstrated enhanced osseointegration, bacteriostasis, and anti-inflammatory effects in vivo.

11.
Polymers (Basel) ; 16(18)2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39339093

RESUMEN

Gene therapy is the technique of inserting foreign genetic elements into host cells to achieve a therapeutic effect. Although gene therapy was initially formulated as a potential remedy for specific genetic problems, it currently offers solutions for many diseases with varying inheritance patterns and acquired diseases. There are two major groups of vectors for gene therapy: viral vector gene therapy and non-viral vector gene therapy. This review examines the role of a macromolecule's chemical and physical architecture in non-viral gene delivery, including their design and synthesis. Polymers can boost circulation, improve delivery, and control cargo release through various methods. The prominent examples discussed include poly-L-lysine, polyethyleneimine, comb polymers, brush polymers, and star polymers, as well as hydrogels and natural polymers and their modifications. While significant progress has been made, challenges still exist in gene stabilization, targeting specificity, and cellular uptake. Overcoming cytotoxicity, improving delivery efficiency, and utilizing natural polymers and hybrid systems are vital factors for prospects. This comprehensive review provides an illuminating overview of the field, guiding the way toward innovative non-viral-based gene delivery solutions.

12.
Turk J Chem ; 48(4): 512-523, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39296793

RESUMEN

Cinchona alkaloid-derived sulfonamides and ester dimers containing chiral hyperbranched polymers have been successfully synthesized and applied as catalysts in asymmetric reactions. Several hyperbranched polymers derived from cinchona alkaloids, incorporating sulfonamides and esters, were synthesized through Mizoroki-Heck coupling polymerization. These polymers were subsequently applied in enantioselective Michael addition reactions. As the prepared polymers are not soluble in frequently used organic solvents, they act as efficient catalysts in the enantioselective reaction of ß-ketoesters to nitroolefins, achieving up to 99% enantioselectivity with good yields. The insoluble property allows them to better satisfy "green chemistry" requirements and be used several times without losing the enantioselectivity.

13.
Int J Biol Macromol ; 279(Pt 2): 135151, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39214207

RESUMEN

The inherent hydrophilicity and biocompatibility of cotton fabrics facilitated bacterial proliferation and safety concerns, limiting their applications. To address these issues, tyrosine-derived polyetherimide, bis(3-aminopropyl)-terminated poly(dimethylsiloxane), and paraformaldehyde were used to synthesize hyperbranched benzoxazine THB-BOZs-PDMS with potent antibacterial and antibiofilm activity. The protonated amino groups of benzoxazine facilitated electrostatic interactions with negatively charged bacteria, and hydrophobic interactions disrupted the cell membrane, leading to bacteria death. Notably, phytic acid interacts with benzoxazines through intermolecular forces, with its phosphoric acid groups facilitating the curing of benzoxazines, thereby imparting flame-retardant properties to the material. Consequently, a multifunctional coating was developed via LBL self-assembly and in-situ curing of benzoxazines and phytic acid on the fabric surfaces. The successful deposition of the coating was confirmed through compositional analysis and morphological characterization. After 4 cycles of LBL modification, the fabrics TBP + PA-CF-4 displayed outstanding antibacterial efficacy, bacterial anti-adhesion properties, and heat resistance. Furthermore, TBP + PA-CF-4 exhibited notable washing and mechanical durability, attributed to the stability conferred by in-situ cured of layers. Compared with other reported modified fabrics, TBP + PA-CF-4 displayed more comprehensive overall performances. These multifunctional fabrics provided a sustainable approach for advancing personal protective materials and public decoration, particularly suited for use in high-humidity environments or military settings.


Asunto(s)
Antibacterianos , Fibra de Algodón , Interacciones Hidrofóbicas e Hidrofílicas , Ácido Fítico , Tirosina , Antibacterianos/farmacología , Antibacterianos/química , Ácido Fítico/química , Ácido Fítico/farmacología , Tirosina/química , Tirosina/farmacología , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Staphylococcus aureus/efectos de los fármacos , Biopelículas/efectos de los fármacos
14.
Int J Biol Macromol ; 279(Pt 1): 135226, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39216576

RESUMEN

Polylactic acid (PLA) wood-plastic composites have a significant advantage over traditional petroleum-based plastics due to their biodegradability. However, PLA has several shortcomings, including high brittleness, low heat resistance, slow crystallization, and poor compatibility with biomass materials, which have limited its potential applications. In this paper, we investigated the effects of carboxy-terminated hyperbranched polyester (CHBP) on the mechanical, crystalline, and thermal properties of PLA/straw flour (SF) blends through extrusion injection molding. Additionally, we added the traditional plasticizer polyethylene glycol (PEG) to synergize with CHBP to enhance the toughness of PLA/SF composites. Our results showed that the appropriate addition of CHBP effectively improved the interfacial bonding between PLA and straw flour. The incorporation of CHBP also improved the tensile strength, bending strength, impact strength, elongation at break, thermal stability, and crystallization rate of the composites. Furthermore, the addition of both CHBP and PEG significantly improved the impact strength of the composites compared to using PEG alone. This method also improved the heat resistance of the material and reduced the migration of plasticizers. Our study demonstrates the feasibility of using hyperbranched polymers and plasticizers to enhance the toughness, thermal stability, and crystalline properties of PLA wood-plastic composites, providing a new approach to improving the properties of these composites.


Asunto(s)
Poliésteres , Polietilenglicoles , Poliésteres/química , Polietilenglicoles/química , Harina , Resistencia a la Tracción , Plastificantes/química , Fenómenos Mecánicos , Cristalización , Ensayo de Materiales
15.
Materials (Basel) ; 17(15)2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39124425

RESUMEN

Due to their excellent properties, antimicrobial fiber membranes are widely applied in bioprotective materials. This work addresses the preparation of thermoplastic polyurethane (TPU)-based fiber membranes with active antimicrobial properties. 2-hydroxypropyl trimethyl ammonium chloride-terminated hyperbranched polymer (HBP-HTC) was synthesized and used as an antimicrobial agent. The fiber membranes were obtained by electrospinning a mixed solution of HBP-HTC and TPU. Different electrospinning conditions were investigated, such as the spinning voltage and drum rotation speed. The fiber membrane prepared under a 22 kV anode voltage and 100 rpm rotation speed had an average fiber diameter of 1.66 µm with a concentrated diameter distribution. Antibacterial tests showed that when the fiber membrane was loaded with 1500 mg/kg of HBP-HTC, the antibacterial rates of E. coli as well as S. aureus both reached 99.99%, exhibiting excellent proactive antimicrobial performance. Moreover, the protective performance of the fiber membrane was outstanding, with a filtration efficiency of 99.9%, a hydrostatic pressure resistance greater than 16,758 Pa, and a moisture permeability of 2711.0 g⋅(m2⋅d)-1.

16.
Molecules ; 29(15)2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39125045

RESUMEN

In order to improve dispersibility, polymerization characteristics, chemical stability, and magnetic flocculation performance, magnetic Fe3O4 is often assembled with multifarious polymers to realize a functionalization process. Herein, a typical three-dimensional configuration of hyperbranched amino acid polymer (HAAP) was employed to assemble it with Fe3O4, in which we obtained three-dimensional hyperbranched magnetic amino acid composites (Fe3O4@HAAP). The characterization of the Fe3O4@HAAP composites was analyzed, for instance, their size, morphology, structure, configuration, chemical composition, charged characteristics, and magnetic properties. The magnetic flocculation of kaolin suspensions was conducted under different Fe3O4@HAAP dosages, pHs, and kaolin concentrations. The embedded assembly of HAAP with Fe3O4 was constructed by the N-O bond according to an X-ray photoelectron energy spectrum (XPS) analysis. The characteristic peaks of -OH (3420 cm-1), C=O (1728 cm-1), Fe-O (563 cm-1), and N-H (1622 cm-1) were observed in the Fourier transform infrared spectrometer (FTIR) spectra of Fe3O4@HAAP successfully. In a field emission scanning electron microscope (FE-SEM) observation, Fe3O4@HAAP exhibited a lotus-leaf-like morphological structure. A vibrating sample magnetometer (VSM) showed that Fe3O4@HAAP had a relatively low magnetization (Ms) and magnetic induction (Mr); nevertheless, the ferromagnetic Fe3O4@HAAP could also quickly respond to an external magnetic field. The isoelectric point of Fe3O4@HAAP was at 8.5. Fe3O4@HAAP could not only achieve a 98.5% removal efficiency of kaolin suspensions, but could also overcome the obstacles induced by high-concentration suspensions (4500 NTU), high pHs, and low fields. The results showed that the magnetic flocculation of kaolin with Fe3O4@HAAP was a rapid process with a 91.96% removal efficiency at 0.25 h. In an interaction energy analysis, both the UDLVO and UEDLVO showed electrostatic repulsion between the kaolin particles in the condition of a flocculation distance of <30 nm, and this changed to electrostatic attraction when the separation distance was >30 nm. As Fe3O4@ HAAP was employed, kaolin particles could cross the energy barrier more easily; thus, the fine flocs and particles were destabilized and aggregated further. Rapid magnetic separation was realized under the action of an external magnetic field.

17.
Polymers (Basel) ; 16(15)2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39125191

RESUMEN

Nanomedicine is a discipline of medicine that applies all aspects of nanotechnology strategies and concepts for treatment and screening possibilities. Synthetic polymer nanostructures are among the many nanomedicine formulations frequently studied for their potential as vectors. Bioimaging is a valuable diagnostic tool, thus, there is always a demand for new excipients/nanocarriers. In this study, hydrophobic hyperbranched poly(lauryl methacrylate) (PLMA) homopolymers comprised of highly hydrophobic LMA moieties with -COOH polar end groups were synthesized by employing reversible addition-fragmentation chain transfer (RAFT) polymerization. Ethylene glycol dimethacrylate (EGDMA) was utilized as the branching agent. End groups are incorporated through the RAFT agent utilized. The resulting amphiphilic hyperbranched polymer was molecularly characterized by size exclusion chromatography (SEC), Fourier transformation infrared spectroscopy (FT-IR), and 1H-NMR spectroscopy. Pyrene, curcumin, and IR-1048 dye were hydrophobic payload molecules successfully encapsulated to show how adaptable these homopolymer nanoparticles (prepared by nanoprecipitation in water) are as dye nanocarriers. This study demonstrates a simple way of producing excipients by generating polymeric nanoparticles from an amphiphilic, hyperbranched, hydrophobic homopolymer, with a low fraction of polar end groups, for bioimaging purposes.

18.
Heliyon ; 10(15): e35264, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-39161815

RESUMEN

Hydrogels containing antimicrobial materials have emerged as attractive platforms for wound treatment in the past decade due to their favorable bio-mimicking properties, excellent modulation of bacterial infection, and ability to minimize bacterial resistance. Herein, a hybrid combination of polyvinyl alcohol (PVA), hyperbranched poly L-lysine (L), tannic acid decorated AgNPs (AgTA NPs), loaded with Allantoin (Alla) is used to fabricate PLAg-Alla hydrogel dressing via the freeze-thaw method without use of any chemical cross-linker. The PLAg-Alla hydrogel possesses a great structure, is biodegradable, and safe, and exhibits high antibacterial potential, all required for efficient wound healing. The incorporation of AgTA and poly L-lysine (L) within the hydrogel contributes to the enhancement of antibacterial ability, as well as effectively promoting the wound healing. This hybrid hydrogel possessed favorable physicochemical features, robust antibacterial properties, and accelerated wound healing in vivo as promising dressing for the clinical application.

19.
ACS Appl Mater Interfaces ; 16(34): 44767-44779, 2024 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-39143897

RESUMEN

Solid-state lithium-sulfur batteries (SSLSBs) have attracted a great deal of attention because of their high theoretical energy density and intrinsic safety. However, their practical applications are severely impeded by slow redox kinetics and poor cycling stability. Herein, we revealed the detrimental effect of aggregation of lithium polysulfides (LiPSs) on the redox kinetics and reversibility of SSLSBs. As a paradigm, we introduced a multifunctional hyperbranched ionic conducting (HIC) polymer serving as a solid polymer electrolyte (SPE) and cathode binder for constructing SSLSBs featuring high electrochemical activity and high cycling stability. It is demonstrated that the unique structure of the HIC polymer with numerous flexible ether oxygen dangling chains and fast segmental relaxation enables the dissociation of LiPS clusters, facilitates the conversion kinetics of LiPSs, and improves the battery's performance. A Li|HIC SPE|HIC-S battery, in which the HIC polymer acts as an SPE and cathode binder, exhibits an initial capacity of 910.1 mA h gS-1 at 0.1C and 40 °C, a capacity retention of 73.7% at the end of 200 cycles, and an average Coulombic efficiency of approximately 99.0%, demonstrating high potential for application in SSLSBs. This work provides insights into the electrochemistry performance of SSLSBs and provides a guideline for SPE design for SSLSBs with high specific energy and high safety.

20.
Int J Biol Macromol ; 278(Pt 1): 134672, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39134199

RESUMEN

A hyperbranched poly (titanium oxide) (HBPTi) with hydroxyl terminal groups was synthesized via polycondensation reaction as a synergistic modifier with tannin to promote performance of casein-based composite film. The synergistic effects of HBPTis, acquiring different hyperbranched structures, with tannin on the microstructure, mechanical characteristics, barrier against water vapor, and thermal stability of casein-based film were investigated in this work. The tensile strength of the composite films increased from 7.6 MPa to 22.1 MPa, which accounts for 190.79 % increase after the addition of HBPTi compared to casein-tannin films modified with glycerol. The casein-tannin films with the help of HBPTi presented excellent water vapor permeation, thermal stability, and showed nearly 100 % UV absorption in the range 200-400 nm. Additionally, the microstructure of HBPTi modified casein-tannin films tend to be more compact due to the promoted interaction of casein-tannin composite aided by covalent bonding and/or other types of bonding between casein, tannin and HBPTi. Therefore, associative modification using such hyperbranched polymers and tannins provides extendable application value for casein-based films especially as food packaging materials and for other fields as well.


Asunto(s)
Caseínas , Taninos , Caseínas/química , Taninos/química , Embalaje de Alimentos/métodos , Polímeros/química , Resistencia a la Tracción , Vapor , Permeabilidad
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