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1.
Int J Biol Macromol ; 277(Pt 4): 134357, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39102916

RESUMO

Developing durable protective cotton fabrics (CF) against potential environmental dangers such as fire hazards and bacterial growth remains an imperative but tough challenge. In this study, flame retardant, antibacterial and hydrophobic CF were successfully prepared via two-step coating. The inner coating entailed polyelectrolyte complexes consisting of polyethyleneimine and ammonium polyphosphate with the goal of enhancing the flame retardancy of CF. Halloysite nanotubes (HNTs), a kind of tubular silicate mineral, were creatively modified and introduced to multifunctional coatings to improve flame retardant and antibacterial properties of CF. N-halamine modified HNTs (HNTs-EA-Cl) and polydimethylsiloxane were applied as the outer coating to endow CF with antibacterial and hydrophobic properties and further improve the flame retardancy of CF. After halloysite-based inorganic-organic hybrid coatings, the limiting oxygen index of the treated samples (PAHP-CF) was over 28 %, and the release of heat and smoke was significantly inhibited. PAHP-CF could inactivate 100 % E. coli and S. aureus within 2 h. More importantly, PAHP-CF showed excellent hydrophobicity with a water contact angle of 148° and exhibited great prevention of bacterial adhesion. PAHP-CF exhibited excellent washing durability undergoing 5 washing cycles. This study promotes the development of multifunctional coatings and offers a new way to manufacture multifunctional cotton fabrics.


Assuntos
Antibacterianos , Argila , Fibra de Algodão , Escherichia coli , Retardadores de Chama , Interações Hidrofóbicas e Hidrofílicas , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Argila/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Nanotubos/química , Têxteis , Polietilenoimina/química , Aderência Bacteriana/efeitos dos fármacos , Aminas , Fosfatos
2.
Int J Biol Macromol ; 278(Pt 3): 135023, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39182887

RESUMO

The design and fabrication of synergistic hybrid antibacterial materials is a promising approach for achieving effective sterilization while compensating for the deficiency of a single component. Despite being highly effective biocidal components, the poor UV light stability of some N-halamines limits their applications. This study was conducted to address this issue by the rational integration of cyclic N-halamine precursor (PGHAPA) with microwaved zinc oxide (MWPPy-ZnO) nanoparticles via covalent bonds and the preparation of cellulose nanofibrils based antibacterial composite films after chlorination (CNF/MWPPy-ZnO-PGHAPA-Cl). The proposed films offered tight lamellar structure, considerable thermal stability and better mechanical properties. The results from the FT-IR and XPS experiments provided the evidence of chemical reactions among the PGHAPA, MWPPy-ZnO, and CNF film. Notably, the CNF/MWPPy-ZnO-PGHAPA-Cl films showed improved UV stability with a chlorine content of up to 0.16 % after 24 h of irradiation, which was much greater than that of the CNF/PGHAPA-Cl films. Furthermore, the CNF/MWPPy-ZnO-PGHAPA-Cl films displayed rapid bactericidal activity, inactivating all the contacted Staphylococcus aureus and Escherichia coli O157:H7 strains within 5 min, along with prominent biofilm disruption, indicating great potential for daily food packaging applications.


Assuntos
Antibacterianos , Biofilmes , Celulose , Nanofibras , Raios Ultravioleta , Óxido de Zinco , Celulose/química , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Nanofibras/química , Aminas/química , Staphylococcus aureus/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Testes de Sensibilidade Microbiana , Escherichia coli/efeitos dos fármacos
3.
Materials (Basel) ; 17(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38893835

RESUMO

In this paper, the possibility of retreated lithium slag (RTLS) with a high content of alkali, sulfate and fluoride as a partial replacement for fly ash (FA) to produce autoclaved aerated concrete (AAC) was investigated. The influence of the RTLS dosage on the AAC performance were examined. The composition and microstructure of hydrates as well as the microstructure of the RTLS-FA-based AAC compositions were determined by XRD, FTIR, TG-DSC and SEM. The results illustrated that the incorporation of RTLS changed the crystal structure and the microstructure of the tobermorite. With increased RTLS contents, the morphology of tobermorite was changed, and the grass-like tobermorite gradually transformed into network-like tobermorite. The newly formed tobermorite improved the mechanical performance of the AAC. Compared with the RTLS10, the content of tobermorite in the RTLS30 increased by 8.6%.

4.
J Orthop Surg Res ; 18(1): 484, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37408002

RESUMO

BACKGROUND: The influence of total en bloc spondylectomy (TES) on spinal stability is substantial, necessitating strong fixation to restore spinal stability. The transverse connector (TC) serves as a posterior spinal instrumentation that connects the left and right sides of the pedicle screw-rod system. Several studies have highlighted the potential of a TC in enhancing the stability of the fixed segments. However, contradictory results have suggested that a TC not only fails to improve the stability of the fixed segments but also might promote stress associated with internal fixation. To date, there is a lack of previous research investigating the biomechanical effects of a TC on TES. This study aimed to investigate the biomechanical effects of a TC on internal fixation during TES of the lumbar (L) spine. METHODS: A single-segment (L3 segment) TES was simulated using a comprehensive L spine finite element model. Five models were constructed based on the various positions of the TC, namely the intact model (L1-sacrum), the TES model without a TC, the TES model with a TC at L1-2, the TES model with a TC at L2-4, and the TES model with a TC at L4-5. Mechanical analysis of these distinct models was conducted using the Abaqus software to assess the variations in the biomechanics of the pedicle screw-rod system, titanium cage, and adjacent endplates. RESULTS: The stability of the surgical segments was found to be satisfactory across all models. Compared with the complete model, the internal fixation device exhibited the greatest constraint on overextension (95.2-95.6%), while showing the least limitation on left/right rotation (53.62-55.64%). The application of the TC had minimal effect on the stability of the fixed segments, resulting in a maximum reduction in segment mobility of 0.11° and a variation range of 3.29%. Regardless of the use of a TC, no significant changes in stress were observed for the titanium cage. In the model without the TC, the maximum von Mises stress (VMS) for the pedicle screw-rod system reached 136.9 MPa during anterior flexion. Upon the addition of a TC, the maximum VMS of the pedicle screw-rod system increased to varying degrees. The highest recorded VMS was 459.3 MPa, indicating a stress increase of 335.5%. Following the TC implantation, the stress on the adjacent endplate exhibited a partial reduction, with the maximum stress reduced by 27.6%. CONCLUSION: The use of a TC in TES does not improve the stability of the fixed segments and instead might result in increased stress concentration within the internal fixation devices. Based on these findings, the routine utilisation of TC in TES is deemed unnecessary.


Assuntos
Parafusos Pediculares , Fusão Vertebral , Análise de Elementos Finitos , Titânio , Fusão Vertebral/métodos , Vértebras Lombares/cirurgia , Fixadores Internos , Amplitude de Movimento Articular , Fenômenos Biomecânicos
5.
Langmuir ; 38(34): 10716-10727, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35980368

RESUMO

Nanofibrillated cellulose (NFC)-based aerogels have been widely used for various applications. However, the disadvantages of poor structural stability, low mechanical toughness, and easy contamination by bacteria hinder their large-scale application. In this work, 3-(3'-acrylicacidpropylester)-5,5-dimethyl hydantoin (APDMH) was grafted on oxidized NFC (ONC) to prepare antibacterial poly(APDMH)-g-ONC (PAC). PAC and poly(ethyleneimine) (PEI) were chemically cross-linked using 3-glycidoxypropyltrimethox (GPTMS), aiming at constructing a PAC-g-PEI aerogel with multiple network structures. The mechanical behaviors of composite aerogel and oil/water separation performances under different conditions were investigated. PAC-g-PEI aerogel exhibits outstanding fatigue resistance (>50 cycles of compression) and superior elasticity (96.76% height recovery after five compression-release cycles at 50% strain). The obtained superhydrophilic and underwater-oleophobic properties endow the aerogel with excellent oil/water separation performances, achieving a satisfactory separation efficiency of over 99% and flux of over 9500 L·m-2·h-1. Furthermore, the chlorinated aerogel of PAC-g-PEI-Cl shows highly efficient and rechargeable antibacterial properties, can inactivate 6.72-log Escherichia coli and 6.60-log Staphylococcus aureus within 10 min, and can still kill all inoculated bacteria after 50 cycles. In addition, PAC-g-PEI-Cl aerogel can inhibit biofilm formation, making it a promising candidate for highly efficient oil/water separation applications in diverse harsh conditions.


Assuntos
Antibacterianos , Celulose , Antibacterianos/farmacologia , Bactérias , Celulose/química , Elasticidade , Géis/química
6.
Int J Biol Macromol ; 216: 86-94, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35788002

RESUMO

Lignin and its derivatives can be used to make membranes with natural polymer materials for its properties including ultraviolet adsorption, biodegradable, antibacterial, and antioxidant. However, the lignin film has poor transparency due to the dark color, and how to control the proportion of each component to enhance properties is the main research topic. In this study, a polyvinyl alcohol /alkaline lignin (PVA/AL) composite film with excellent UV-shielding and visible-transparent performance successfully prepared by solution casting. By mixing with the N-halamine precursor 3-(2,3-dihydroxypropyl)-5,5-dimethylhydantoin (DPDMH), the composite film after chlorination showed superb antibacterial efficacy and could inactivate 6.85 log Escherichia coli (E. coli) and 6.57 log Staphylococcus aureus (S. aureus) respectively within 5 min of contact. Moreover, the composite film with 5 wt% AL exhibited ultra-high elongation of 449 % and toughness of 92 MJ/m3, and the toughness and malleability was greatly improved. In addition, with the introduction of AL, the composite film could shield 100 % of the UVB (320-275 nm) and UVC (275-200 nm) spectra and most of the UVA (400-320 nm) spectrum. The films prepared in this work are expected to find applications in promising fields such as in packaging materials and ultraviolet shielding.


Assuntos
Lignina , Staphylococcus aureus , Antibacterianos/farmacologia , Escherichia coli , Lignina/farmacologia , Álcool de Polivinil/farmacologia
7.
Carbohydr Polym ; 292: 119615, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35725195

RESUMO

Anti-infections therapy accompanied with effective hemorrhage control is highly urgent in clinics. Herein, a biomimetic nanoreactor encapsulated self-healing hydrogel with glucose-responsive catalytic activity was constructed for synergetic antibacterial defense and hemostasis. A metal-organic frameworks (MOF)-based nanocatalyst loaded with glucose oxidase (GOx) was fabricated and encapsulated in the bacterial cellulose (BC) reinforced hydrogel, while the sustained release of GOx could catalyze the decomposition of glucose for triggering the MOF-mediated catalytic activity to in situ generate OH for bacteria killing. Importantly, this nanozyme-based hydrogel exhibited excellent hemostatic property owing to the enhanced absorption capacity, which provides the essential glucose from blood for triggering the glucose-responsive antibacterial activity simultaneously. Antibacterial tests revealed that the hydrogel exhibited significant antibacterial efficacy and biofilm inhibition ability in the presence of normal blood level of glucose. Such design of biocatalytic hydrogel for synergistic hemostatic and antibacterial application brings new insight for nanozyme-based biomedical therapies.


Assuntos
Hemostáticos , Estruturas Metalorgânicas , Antibacterianos/farmacologia , Bactérias , Biomimética , Celulose/farmacologia , Glucose/farmacologia , Glucose Oxidase , Hemostasia , Hemostáticos/farmacologia , Hidrogéis/farmacologia , Estruturas Metalorgânicas/farmacologia , Nanotecnologia
8.
Int J Biol Macromol ; 195: 294-301, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34914907

RESUMO

Reactive oxygen species (ROS) for treating bacterial infection is an alternative strategy to overcome the drawbacks such as bacterial resistance of commonly used antibiotics. Nanocatalysts have been proved highly effective in regulating intracellular ROS level due to their intrinsic enzymes-mimicking ability. Herein, we prepared a carbon-based nanozyme doped with copper atoms with peroxidase mimetic activity to catalyze the decomposition of bio-safety dosage of H2O2 to highly reactive OH radicals for antibacterial treatment. Furthermore, we designed the thermo-responsive nanogels consisting of bacterial cellulose nanowhiskers as the carrier of the nanozyme. The obtained nanogels displayed remarkable intelligent response to temperature change with sol-gel transition temperature of ~33 °C and in situ gel forming ability. Moreover, the nanogels exhibited excellent biocompatibility in vitro, along with remarkable antibacterial efficacy which could inactivate 6.36 log of S. aureus and 6.01 log of E. coli in 3 h, respectively. The findings provide a novel strategy for advancing the development of nanocatalysts-based responsive biomaterials for treating bacterial infections.


Assuntos
Antibacterianos/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Nanogéis/química , Antibacterianos/farmacologia , Materiais Biocompatíveis , Catálise , Celulose , Escherichia coli , Peróxido de Hidrogênio , Testes de Sensibilidade Microbiana , Nanopartículas , Espécies Reativas de Oxigênio/química , Staphylococcus aureus
9.
Mater Sci Eng C Mater Biol Appl ; 131: 112493, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34857279

RESUMO

Bacterial infections are the major challenges of wound treatment in current clinical applications. In this study, Three-dimensional (3D) antibacterial wound dressing has been fabricated via introducing N-halamine/TiO2 to gelatin methacrylate and xanthan gum. The prepared 3D printed dressings showed ideal swelling ratio and excellent water uptake efficiency. TiO2 nanoparticles were introduced by in-situ to improve the ultraviolet stability of N-halamines. The 3D printed GX2-TiO2-PSPH-Cl prepared dressings containing titanium dioxide retained 0.19% active chlorine after ultraviolet irradiation for 20 min, which was much higher than that of N-halamine dressings without the addition of TiO2. The 3D printed dressings showed good antibacterial activity, and 100% of Escherichia coli O157:H7 and Staphylococcus aureus were inactivated after 60 min of contact. Furthermore, the biofilm test indicated that the 3D antibacterial dressings were able to inhibit the formation of bacterial biofilm. The 3D printed dressings possess outstanding biocompatibility. Moreover, in vivo data demonstrated that the 3D printed dressings could significantly accelerate wound healing in a mouse model, indicating that the developed 3D printed dressings are ideal candidates for wound treatment.


Assuntos
Bandagens , Cicatrização , Animais , Antibacterianos/farmacologia , Biofilmes , Camundongos , Polissacarídeos Bacterianos , Porosidade , Impressão Tridimensional
10.
Des Monomers Polym ; 24(1): 162-172, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34104074

RESUMO

Electrospinning provides a versatile, efficient and low-cost method for the preparation of continuous nanofibres from various polymers. In this study, the polyhedral oligomeric silsesquioxanes (POSS) block copolymer was synthesized via atom transfer radical polymerization. The smooth fiber, porous fiber or hierarchically porous microspheres were prepared by electrospinning from POSS block copolymer, poly(vinylidene fluoride) (PVDF) and aluminium oxide (Al2O3). The influence of copolymer concentration, the ratio of the solvents, the diameter and concentration of the Al2O3 on the surface morphology were investigated. Porous fibers and porous microspheres were prepared by regulating the ratio of the solvents from the phase separation and breath figure methods. The dynamic behavior of the water droplet with the constant volume impacting on the electrospinning films were reported. The morphology evolution, restitution coefficient, the change of energy of the water droplets are examined. The droplet bounces several times on the superhydrophobic surface, while the droplet remains pinned and does not rebound when the contact angles was lower than 150°. On the other hand, the water droplets were splashed on the Al2O3 based electrospinning films. Finally, the mechanical properties of the electrospinning films were investigated.

11.
Carbohydr Polym ; 266: 118129, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34044945

RESUMO

In this study, we constructed a novel family of chitosan-based cryogels with antibacterial activity to treat different types of dye wastewater. Glycidyl methacrylate (GMA) cross-linked chitosan (CS) cryogels functionalized with negatively and positively molecules were prepared via thermo-crosslinking and freeze-drying methods. These chitosan-based cryogels present a well-defined three-dimensional microporous network structure with ultra-light and high porosity, and have high water absorption ability. For CS/GMA/SMA cryogels, 71.20% of Cationic Yellow X-8GL (CY) can be removed, and the process kinetics well corresponded to the Pseudo-second order model and Freundlich model. The quantity and percent of Reactive Yellow B-4RFN (RY) removal by CS/GMA/DMC cryogel reached at 224.6 mg/g and 96.11%, which closely fitted the Pseudo-second order model and Dubinin-Radushkevich isotherm. Furthermore, the chitosan-based cryogels showed antibacterial efficacies against E. coli and S. aureus. The prepared chitosan-based cryogels with adsorption and antibacterial properties have great potential for the remediation of dyeing wastewater.


Assuntos
Antibacterianos/farmacologia , Quitosana/farmacologia , Corantes/isolamento & purificação , Criogéis/farmacologia , Compostos de Epóxi/farmacologia , Metacrilatos/farmacologia , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Antibacterianos/química , Compostos Azo/química , Compostos Azo/isolamento & purificação , Quitosana/química , Corantes/química , Criogéis/síntese química , Criogéis/química , Compostos de Epóxi/química , Escherichia coli/efeitos dos fármacos , Metacrilatos/química , Testes de Sensibilidade Microbiana , Porosidade , Extração em Fase Sólida/métodos , Staphylococcus aureus/efeitos dos fármacos , Poluentes Químicos da Água/química , Purificação da Água/métodos
12.
ACS Appl Mater Interfaces ; 13(12): 14688-14699, 2021 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-33739108

RESUMO

Developing a new family of hydrogel-based wound dressings that could have a dual biofunctionality of antibacterial and biological responses is highly desirable. In this study, an inherently effective antibacterial and biodegradable hydrogel dressing without the need for impregnated antibiotics was designed, synthesized, characterized, and examined for its effect on macrophages, which initiated inflammatory activity and activated both NO and TNF-α production for the purpose of achieving a better and faster wound healing. The purposes of this research was to develop a novel family of cationic biodegradable hydrogels based on arginine-based poly(ester urea urethane) (Arg-PEUU) and glycidyl methacrylate-modified chitosan (CS-GMA) that has both inherent antibacterial and bioactive functionality as a wound healing dressing for accelerated healing of contaminated or infected wounds. These hybrid hydrogels present a well-defined three-dimensional microporous network structure and have a high water absorption ability, and their biodegradation is effectively accelerated in the presence of lysozymes. The hemolytic activity test, MTT assay, and live/dead assay of these hybrid hydrogels indicated that they had no cytotoxicity toward red blood cells, NIH-3T3 fibroblast cells, and human vascular endothelial cells, thus corroborating their cytocompatibility. Furthermore, these hybrid hydrogels could elevate the release of both produced NO and TNF-α by stimulating and activating RAW 264.7 macrophages, augmenting their antibacterial biological response. The antibacterial assay of these hybrid hydrogels demonstrated their excellent antibacterial activity without the need for impregnated antibacterial agents. Taken together, this new family of biodegradable, antibacterial, and biologically responsive hybrid hydrogels exhibits great potential as biofunctional antibacterial wound dressing candidates for wound healing.


Assuntos
Antibacterianos/química , Arginina/análogos & derivados , Bandagens , Quitosana/análogos & derivados , Hidrogéis/química , Poliésteres/química , Animais , Antibacterianos/farmacologia , Arginina/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Quitosana/farmacologia , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Humanos , Hidrogéis/farmacologia , Metacrilatos/química , Metacrilatos/farmacologia , Camundongos , Células NIH 3T3 , Poliésteres/farmacologia , Células RAW 264.7 , Cicatrização/efeitos dos fármacos
13.
Carbohydr Polym ; 253: 117205, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278975

RESUMO

In this work, a novel chitosan based structure (CS/EVC) with low density, high porosity, three-dimensional porous structure and great adsorption capability has been prepared by using 1,2-epoxy-4-vinyl cyclohexane (EVC) as a cross-linker. After immersing CS/EVC in N-halamine 1-chloro-2,2,5,5-tetramethyl-4-imidazolinone (MC) solution, antibacterial CS/EVC/MC compounds were obtained. Compared with chitosan and CS/EVC controls, CS/EVC/MC showed excellent antimicrobial activities, which could inactivate both more than 6 logs (×1/1,000,000) of Staphylococcus aureus (ATCC 6538) and Escherichia coli (ATCC 8099) within 30 and 10 min, respectively. Moreover, the relatively low blood clotting index of CS/EVC/MC and the activation of platelets adhering to the surfaces indicated that the CS/EVC/MC sample is potential to promote the agglutination abilities of blood cells and simultaneously control wound bleeding. In addition, in vitro cytotoxicity test showed that the CS/EVC/MC had no cytotoxicity. The material might thus have a great potential for biomedical applications.


Assuntos
Aminas/química , Antibacterianos/química , Coagulação Sanguínea/efeitos dos fármacos , Quitosana/química , Escherichia coli/efeitos dos fármacos , Hemostáticos/química , Staphylococcus aureus/efeitos dos fármacos , Células 3T3 , Adsorção , Animais , Antibacterianos/farmacologia , Reagentes de Ligações Cruzadas/química , Compostos de Epóxi/química , Hemorragia/tratamento farmacológico , Hemostáticos/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Porosidade , Coelhos , Compostos de Vinila/química , Cicatrização/efeitos dos fármacos
14.
Polymers (Basel) ; 12(11)2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33137972

RESUMO

Cellulose is one of the most hydrophilic polymers with sufficient water holding capacity but it is unstable in aqueous conditions and it swells. Cellulose itself is not suitable for electrospun nanofibers' formation due to high swelling, viscosity, and lower conductivity. Carboxymethyl cellulose (CMC) is also super hydrophilic polymer, however it has the same trend for nanofibers formation as that of cellulose. Due to the above-stated reasons, applications of CMC are quite limited in nanotechnology. In recent research, loading of CMC was optimized for electrospun tri-component polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), and carboxymethyl cellulose (CMC) nanofibers aim at widening its area of applications. PVA is a water-soluble polymer with a wide range of applications in water filtration, biomedical, and environmental engineering, and with the advantage of easy process ability. However, it was observed that only PVA was not sufficient to produce PVA/CMC nanofibers via electrospinning. To increase spinnability of PVA/CMC nanofibers, PVP was selected as the best available option because of its higher conductivity and water solubility. Weight ratios of CMC and PVP were optimized to produce uniform nanofibers with continuous production as well. It was observed that at a weight ratio of PVP 12 and CMC 3 was at the highest possible loading to produce smooth nanofibers.

15.
Mater Sci Eng C Mater Biol Appl ; 115: 111122, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32600721

RESUMO

Microbial contamination and biofilm formation cause serious issues in medical, household, industrial and environmental applications. In this study, a series of cationic and anionic N-halamine polymeric precursors, poly (N,N-dimethyl-N-decyl ammonium ethyl methacrylate-co-methacrylamide) (PQDM) and poly (acrylic acid-co-methacrylamide) (PAM), were synthesized and coated onto cotton fabrics through the layer-by-layer (LBL) assembly technique. The coated LBL cotton swatches were characterized by Scanning Electron Microscopy, Fourier transform infrared spectroscopy, and contact angle evaluation. The stability of the LBL samples towards artificial sweat and home laundering was evaluated. The LBL treated fabrics demonstrated effective antimicrobial efficacy and biofilm-controlling against Gram-positive bacteria, Gram-negative bacteria, and Fungi. In vitro cytocompatibility test towards mouse fibroblast cell indicated that the LBL coated cotton fabrics are cytocompatible, pointing to great potentialities of the LBL assembled fabrics for future biomedical applications.


Assuntos
Aminas/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Compostos de Amônio Quaternário/farmacologia , Aminas/química , Animais , Antibacterianos/química , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Linhagem Celular , Fibra de Algodão , Eletrólitos , Escherichia coli/efeitos dos fármacos , Escherichia coli/fisiologia , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Compostos de Amônio Quaternário/química , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/fisiologia
16.
Int J Biol Macromol ; 161: 1070-1078, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32531364

RESUMO

Bacterial cellulose (BC) is a natural polymer with remarkable superiority for fabricating biomaterials. In this study, a multiporous bacterial cellulose (MBC) film was modified with N-isopropylacrylamide (NIPAM), and the modified MBC film was imbued with antibacterial properties after chlorination. The dried chlorinated samples showed superb antibacterial efficacy and could inactivate 6.19 log of inoculated S. aureus and 6.29 log of E. coli within 1 min of contact. After releasing active chlorine for 12 h, 3.67 log of S. aureus and 3.97 log of E. coli were inactivated within 30 min of contact. The prepared films displayed high porous and layered structures with a resultant excellent water retention which can be applied as material for wound dressings. In addition, the chlorinated films showed hemostatic ability on wound bleeding and good biocompatibility. The prepared N-halamine functionalized MBC films might have great potential applications as wound dressings.


Assuntos
Aminas/química , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/química , Celulose/química , Hemostasia/efeitos dos fármacos , Animais , Materiais Biocompatíveis/química , Sobrevivência Celular/efeitos dos fármacos , Cloro/química , Concentração de Íons de Hidrogênio , Camundongos , Testes de Sensibilidade Microbiana , Adesividade Plaquetária/efeitos dos fármacos , Porosidade
17.
Carbohydr Polym ; 243: 116461, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32532394

RESUMO

The aim of this study was to develop novel aerogels based on nanocrystalline cellulose (NCC), and chitosan (CS) for oily wastewater treatment. The quaternarized N-halamine siloxane monomer (QHS) was successfully synthesized and hydrolyzed to form quaternarized N-halamine siloxane polymer (PQHS) in the mixture of NCC and CS solution to improve the antibacterial properties of aerogels. The strong hydrophilicity of natural polymers NCC and CS and the microporous structure of aerogel endow the underwater oleophobic property. The applications of the aerogels as filter materials for oil/water separation are studied, and showed high separation efficiency of different types of oil/water mixtures. The presence of N-halamine structures in PQHS makes the aerogels effectively kill bacteria in oily sewage and inhibit the growth of bacteria on the surface of the materials. The properties of exceptional reusability, oil/water separation efficiency, and antibacterial efficacies render the aerogels as promising materials with potential applications in oily wastewater treatment.


Assuntos
Antibacterianos/química , Desinfecção , Emulsões/química , Géis/química , Nanopartículas/química , Purificação da Água , Adsorção , Aminas/química , Aminas/farmacologia , Bactérias/efeitos dos fármacos , Celulose/química , Quitosana/química , Óleos/química , Siloxanas/química , Propriedades de Superfície , Poluentes Químicos da Água/química
18.
Carbohydr Polym ; 232: 115823, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31952618

RESUMO

The aim of this study was to develop novel nanofibrous membranes based on the quaternary ammonium N-halamine chitosan (CSENDMH) and polyvinyl alcohol (PVA) for antibacterial and hemostasis wound dressing. To improve the antimicrobial properties of nanofibrous membranes, a new chitosan-quaternary ammonium N-halamine derivative was successfully synthesized, and the structure was analyzed by 1H NMR and 13C NMR, fourier transform infrared (FTIR) spectroscopy, and elemental analysis. The morphological and water absorption ability studies showed that the membrane had a uniform bead-free network and high porosity structure like natural extracellular matrix as well as high hydrophilicity. For in vitro evaluation of the hemostatic effect, the membranes showed excellent blood clotting capacity, especially the PVA/CSENDMH membranes. The antimicrobial assay demonstrated excellent antibacterial activity of nanofibrous membranes against both gram-negative and gram-positive bacteria. Furthermore, the cytocompatibility assay results indicated that human fibroblasts could adhere and proliferate on the membranes, thus corroborating their biocompatibility.


Assuntos
Aminas/farmacologia , Antibacterianos/farmacologia , Quitosana/farmacologia , Hemostáticos/farmacologia , Nanofibras/química , Álcool de Polivinil/farmacologia , Aminas/química , Antibacterianos/química , Quitosana/química , Escherichia coli O157/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Hemostáticos/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Tamanho da Partícula , Álcool de Polivinil/química , Porosidade , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície
19.
Carbohydr Polym ; 228: 115391, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31635733

RESUMO

Fungal biofilm formation is an emerging problem in a wide range of health-related applications. This study aims to design and synthesize amphiphilic quaternary ammonium chitosans (AQACs) that could bind onto fungal biofilms to kill adherent fungal cells, and establish their structural/fungicidal activity relationships. AQACs with different hydrophobic alkyl chain length (C4, C8, and C12) were synthesized by quaternization of 3-bromopropionic acid with the corresponding tertiary amines, followed by reacting with chitosan using the EDC/NHS chemistry. The new AQACs were soluble in water, yet formed self-aggregates in the solution with different sizes. In antifungal tests against free-floating Candida albicans, shorter alkyl chains (C4) in the AQACs resulted in the most potent fungicidal effect. However, in the treatment of Candida biofilms formed on solid surfaces, AQACs with longer alkyl chains (C8 and C12) were much more effective than their shorter chain counterpart (C4). The effects of alkyl chain self-aggregation on the opposite trend in fungicidal and anti-biofilm activities were discussed. All the AQACs showed excellent cytocompatibility with mammalian cells.


Assuntos
Antifúngicos/química , Biofilmes/efeitos dos fármacos , Quitosana/química , Compostos de Amônio Quaternário/química , Animais , Materiais Biocompatíveis/química , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Linhagem Celular , Conformação Molecular
20.
ACS Appl Mater Interfaces ; 12(2): 2983-2990, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31854969

RESUMO

Herein, we demonstrated a one-step route for the manufacturing of polypyrrole (PPy)/zinc nanohybrids with tunable elemental composition and nanoscale component mixing resolution by using an ultrafast (within tens of seconds) microwave approach for ultrasensitive DNA biosensors. The zinc-based nanoparticles (i.e., MWPPy/ZnO and MWPPy/ZnS) were produced by loading zinc acetate (ZnAc2) on PPy under the electromagnetic environment of a microwave with or without sulfur powder in one pot. Then, the signal amplification platforms were fabricated by modifying the glassy carbon electrode (GCE) with the obtained nanohybrids. It was found that both of the resultant MWPPy/ZnO and MWPPy/ZnS were suitable for ultrasensitive DNA molecule detection of the gastric carcinoma related PIK3CA gene ascribing to their unique hybrid nanostructures and surface characteristics. Experimental results revealed that the proposed GCE/MWPPy/ZnO sensor showed a linear range of 1.0 × 10-10 to 1.0 × 10-13 M. Notably, the GCE/MWPPy/ZnS sensor was endowed with promising DNA hybrid selection with a minimum concentration response of 1.0 × 10-18 M. The corresponding detection limit was, respectively, found to be 2.90 × 10-11 and 7.73 × 10-21 M for MWPPy/ZnO- and MWPPy/ZnS-based biosensors. Furthermore, reliable determination of single-base and two-base mismatched DNA are more attractive, which greatly supported the application of the constructed zinc-based nanohybrids for the detection of single nucleotide polymorphism in genetic diseases, biological infectious pathogens, or warning against bio-warfare agents.


Assuntos
DNA/química , Nanoestruturas/química , Processamento de Sinais Assistido por Computador , Zinco/química , Eletroquímica , Eletrodos , Micro-Ondas , Nanoestruturas/ultraestrutura , Polímeros/química , Pirróis/química , Difração de Raios X , Óxido de Zinco/química
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