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1.
Environ Sci Technol ; 58(17): 7335-7345, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38626301

RESUMO

Interfacial solar vapor generation (ISVG) is an emerging technology to alleviate the global freshwater crisis. However, high-cost, low freshwater collection rate, and salt-blockage issues significantly hinder the practical application of solar-driven desalination devices based on ISVG. Herein, with a low-cost copper plate (CP), nonwoven fabric (NWF), and insulating ethylene-vinyl acetate foam (EVA foam), a multistage device is elaborately fabricated for highly efficient simultaneous freshwater and salt collection. In the designed solar-driven device, a superhydrophobic copper plate (SH-CP) serves as the condensation layer, facilitating rapid mass and heat transfer through dropwise condensation. Moreover, the hydrophilic NWF is designed with rational hydrophobic zones and specific high-salinity solution outlets (Design-NWF) to act as the water evaporation layer and facilitate directional salt collection. As a result, the multistage evaporator with eight stages exhibits a high water collection rate of 2.25 kg m-2 h-1 under 1 sun irradiation. In addition, the desalination device based on the eight-stage evaporator obtains a water collection rate of 13.44 kg m-2 and a salt collection rate of 1.77 kg m-2 per day under natural irradiation. More importantly, it can maintain a steady production for 15 days without obvious performance decay. This bifunctional multistage device provides a feasible and efficient approach for simultaneous desalination and solute collection.


Assuntos
Água Doce , Luz Solar , Salinidade , Purificação da Água
2.
Int J Biol Macromol ; 265(Pt 1): 130781, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492691

RESUMO

Bacterial infected wounds, which is characterized by easy infection, multiple inflammation and slow healing, is a complex symptom, resulting from metabolic disorder of the wound microenvironment. In this study, a series of self-healing double-network hydrogels based on KGRT peptide (Lys-Gly-Arg-Thr) with antibacterial, anti-inflammatory and optimizing cellular functions were designed to promote the healing of infected wounds with full-thickness skin defects. Moreover, the dextran hydrogelintroduces a large number of side chains, which are entangled with each other in the Schiff base network to form an interpenetrating structure. The hydrogel might regulate cell metabolism, differentiation and vascular endothelial growth factor (VEGF) function. Importantly, both in vitro and in vivo data showed that hydrogel not only has good antibacterial properties (99.8 %), but also can eradicate bacterial biofilm, effectively reduce inflammation (down-regulated IL-1ß, TNF-α and ROS) and accelerate chronic wound healing process by speeding-up wound closure, increasing granulation tissue thickness, collagen deposition, angiogenesis (up-regulated CD31). The hydrogel could up-regulate mRNA expression of PI3K, AKT, ERK, eNOS, HIF-1α and VEGF, which were correlated with wound healing. Consistently, the hydrogel could promote infected wounds healing and inhibit inflammation through ERK/eNOS signaling pathway. Collectively, hydrogel has excellent clinical application potential for promoting infected wound healing.


Assuntos
Hidrogéis , Fator A de Crescimento do Endotélio Vascular , Humanos , Hidrogéis/farmacologia , Transdução de Sinais , Cicatrização , Peptídeos , Antibacterianos/farmacologia , Inflamação
3.
Molecules ; 27(19)2022 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-36235310

RESUMO

During the course of a review of our publication, we found two errors in Figure 4b and Figure 9 [...].

4.
Materials (Basel) ; 15(17)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36079298

RESUMO

The dilemma of diminishing freshwater resources caused by water pollution has always impacted human life. Solar-driven interfacial evaporation technology has the potential for freshwater production via solar-driven distillation. However, in solar-driven interfacial evaporation technology, it is difficult to overcome the problem of wastewater containing various contaminants. In this work, we propose a bifunctional fabric created by depositing titanium dioxide@carbon black nanoparticles onto cotton fabric (TiO2@CB/CF). The TiO2@CB/CF has a coupling effect that includes the photothermal effect of CB and photocatalysis of TiO2, and it can not only generate clean water but can also purify contaminated water. The resulting bifunctional fabric can achieve an outstanding water evaporation rate of 1.42 kg m-2 h-1 and a conversion efficiency of 90.4% in methylene blue (MB) solution under one-sun irradiation. Simultaneously, the TiO2@CB/CF demonstrates a high photocatalytic degradation of 57% for MB solution after 2 h with light irradiation. It still shows a good photocatalysis effect, even when reused in an MB solution for eight cycles. Furthermore, the TiO2@CB/CF delivers excellent performance for actual industrial textile dyeing wastewater. This bifunctional fabric has a good application prospect and will provide a novel way to resolve the issue of freshwater scarcity.

5.
Biomater Sci ; 10(17): 4796-4814, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35852356

RESUMO

To meticulously establish an efficient photothermal multifunctional hydrogel dressing is a prospective strategy for the treatment of diabetic chronic wounds. Herein, glucose oxidase (GOx) was added to polydopamine/acrylamide (PDA/AM) hydrogels to reduce hyperglycemia to a normal level (3.9-6.1 mmol L-1) and enhance compressive properties (55 kPa) and adhesive properties (32.69 kPa), which are capable of hemostasis in the wound. Then, MnO2 nanoparticles were encapsulated into a polydopamine/acrylamide (PDA/AM) hydrogel, endowing it with excellent antibacterial properties (E. coli and S. aureus were 97.87% and 99.99%) under the irradiation of 808 nm NIR; meanwhile, the biofilm was eliminated completely. Besides, O2 was generated (18 mg mL-1) by the decomposition of H2O2 under the catalysis of MnO2, which could accelerate the formation of angiogenesis and promote the crawling and proliferation of cells. Furthermore, the diabetic wound in vivo treated with the PDA/AM/GOx/MnO2 hydrogel had a less inflammatory response and faster healing speed, which was completely healed in 14 days. Therefore, the multifunctional hydrogels with the capability of high compressible, hemostasis, antibacterial, hyperglycemia manipulation, and O2 generation, demonstrate promise in diabetic chronic wound dressing.


Assuntos
Diabetes Mellitus , Hiperglicemia , Acrilamidas , Antibacterianos/farmacologia , Bandagens , Escherichia coli , Hemostasia , Humanos , Hidrogéis/farmacologia , Peróxido de Hidrogênio/farmacologia , Hipoglicemiantes/farmacologia , Compostos de Manganês/farmacologia , Óxidos/farmacologia , Staphylococcus aureus
6.
J Colloid Interface Sci ; 618: 462-474, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35364547

RESUMO

Flame retardant and antibacterial investigation of cellulose has attracted more and more attention. In order to improve the modification efficiency, inspired by multiple hydrogen bonding in spider silk, flame retardant and antibacterial dual function modified cellulose was achieved by multi structure hydrogen bonding in this research. A novel nano SiO2 based Schiff base flame retardant (SiAPH) and dodecyl quaternary ammonium salt (HDAC) were synthesized. Tannin (TA) was introduced as medium to provide synergistic flame retardant and antibacterial with SiAPH and HDAC. The flame retardancy assessment demonstrated that the limiting oxygen index (LOI) of modified cotton fabrics increased from 18% to 26.1%, and the peak of heat release rate (pHRR) decreased by 41.0%, UL-94 vertical combustion proved the modified cotton fabrics had capability of self-extinguishing. The antibacterial of modified fabrics were confirmed against Staphylococcus aureus and Escherichia coli, and the inhibition rate reached to 99.1%. In addition, it worth noting that the biocompatibility and antibacterial activity of modified fabrics were evaluated via MTS assay and establishment of animal wound model. Low toxicity of the fabrics was verified by the L929 fibroblast cells. The anti-infection experiment model showed that the modified fabrics had a positive effect on prevention of infection, and the wound healing rate reached to 86.8% after 14 days' treatment. The flame retardancy, antibacterial and biocompatibility of the functional cotton fabrics indicated that they were ideal candidate for applications of vehicle interior, soft decoration in public and medical scene.


Assuntos
Retardadores de Chama , Antibacterianos/farmacologia , Celulose/química , Celulose/farmacologia , Fibra de Algodão , Retardadores de Chama/farmacologia , Têxteis
7.
ACS Appl Mater Interfaces ; 14(14): 15911-15926, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35373564

RESUMO

Bacterial biofilms on wounds can lead to ongoing inflammation and delayed reepithelialization, which brings a heavy burden to the medical systems. Nitric oxide based treatment has attracted attention because it is a promising strategy to eliminate biofilms and heal infected wounds. Herein, a series of tryptophan-based poly(ester urea)s with good biodegradation and biocompatibility were developed for the preparation of composite mats by electrospinning. Furthermore, the mats were grafted with a nitric oxide donor (nitrosoglutathione, GSNO) to provide one type of NO loading cargo. The mats were found to have a prolonged NO release profile for 408 h with a maximum release of 1.0 µmol/L, which had a significant effect on killing bacteria and destructing biofilms. The designed mats were demonstrated to promote the growth of cells, regulate inflammatory factors, and significantly improve collagen deposition in the wound, eventually accelerating wound-size reduction. Thus, the studies presented herein provide insights into the production of NO-releasing wound dressings and support the application of full-thickness wound healing.


Assuntos
Nanofibras , Infecção dos Ferimentos , Antibacterianos/farmacologia , Biofilmes , Ésteres , Humanos , Nanofibras/uso terapêutico , Óxido Nítrico/química , Óxido Nítrico/farmacologia , Triptofano/farmacologia , Ureia/química , Ureia/farmacologia , Cicatrização , Infecção dos Ferimentos/tratamento farmacológico
8.
J Colloid Interface Sci ; 617: 542-556, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35303638

RESUMO

Diabetic wound treatment remains a major challenge due to the difficulties of eliminating bacterial biofilm and relieving wound hypoxia. To address these issues simultaneously, a multifunctional Dex-SA-AEMA/MnO2/PDA (DSAMP) hydrogel platform was developed with excellent biocompatibility and porous structure. The hydrogel could absorb the exudate, maintain humidity and permeate oxygen, which was prepared by encapsulating polydopamine (PDA) and manganese dioxide (MnO2) into Dex-SA-AEMA (DSA) hydrogel by UV irradiation. With the addition of PDA, the DSAMP hydrogel was proved to eliminate the biofilm after NIR photodynamic therapy (PTT, 808 nm) irradiation at 54 °C. Furthermore, in order to mitigate hypoxia wound microenvironment, MnO2 nanoparticles were added to convert the endogenous hydrogen peroxide (H2O2) into oxygen (O2, 16 mg L-1). The diabetic wound in vivo treated by DSAMP hydrogel was completely healed on 14 days. It was revealed that the DSAMP hydrogel possessed a great potential as dressing for diabetic chronic wound healing.


Assuntos
Diabetes Mellitus , Compostos de Manganês , Antibacterianos , Biofilmes , Humanos , Hidrogéis/farmacologia , Peróxido de Hidrogênio , Hipóxia , Óxidos , Oxigênio , Cicatrização
9.
J Colloid Interface Sci ; 607(Pt 2): 1849-1863, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34688976

RESUMO

Infected wounds show delayed and incomplete healing processes and even render patients at a high risk of death due to the formed bacterial biofilms in the wound site, which protect bacteria against antimicrobial treatments and immune response. Nitric oxide based therapy is considered a promising strategy for eliminating biofilms and enhancing wound healing, which encounters a significant challenge of controlling the NO release behavior at the wound site. Herein, a kind of phenylalanine based poly(ester urea)s with high thermal stability are synthesized and fabricated to electrospun films as NO loading vehicle for infected wound treatment. The resultant films can continuously and stably release nitric oxide for 360 h with a total concentration of 1.15 µmol L-1, which presents obvious advantages in killing the bacteria and removing biofilms. The results exhibit the films have no cytotoxicity and may accelerate the wound repair without causing inflammation, hemolysis, or cytotoxic reactions as well as stimulate the proliferation of fibroblasts and increase the synthesis of collagen. Therefore, the films may be a suitable NO releasing dressing for removing biofilms and repairing infected wounds.


Assuntos
Ésteres , Óxido Nítrico , Antibacterianos , Biofilmes , Humanos , Fenilalanina , Ureia , Cicatrização
10.
Mol Nutr Food Res ; 66(5): e2100355, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34914178

RESUMO

SCOPE: Royal jelly (RJ) has a wide range of biological functions, its effect on hyperplasia of the mammary gland (HMG) in mammals is unclear. This study aims to investigate the effect of RJ on HMG and the dose-response relationship of RJ in the treatment of HMG. METHODS AND RESULTS: HMG rats are induced by intramuscular injection of estrogen (E2) and progesterone, and are treated with different doses of RJ (100, 200, 400, and 800 mg kg-1 d-1 ). As a result, RJ improves the expansion of acinar and breast tissue ducts, particularly at 100 and 800 mg kg-1 d-1 . These two doses also inhibit serum E2 and prolactin (PRL) secretion and increase serum progesterone secretion and the expression of estrogen receptor (ER)-ß in the breast tissue. In addition, 800 mg kg-1 d-1 decrease and increase the mRNA expression of, respectively, hypothalamic gonadotropin-releasing hormone (GnRH) and pituitary GnRH receptors (GnRH-R). The lowest dosage (100 mg kg-1 d-1 ) increases GnRH-R mRNA expression as well. However, the effects of 200 and 400 mg kg-1 d-1 RJ on the reproductive parameters of HMG are not significant, implying a dose-dependent effect. CONCLUSION: RJ regulates endocrine dyscrasia in HMG rats and improves the breast tissue structure, indicating its potential in the prevention and treatment on HMG.


Assuntos
Estrogênios , Progesterona , Animais , Estrogênios/farmacologia , Ácidos Graxos , Hormônio Liberador de Gonadotropina/farmacologia , Hiperplasia , Mamíferos , Progesterona/farmacologia , RNA Mensageiro , Ratos
11.
J Colloid Interface Sci ; 603: 243-251, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34186401

RESUMO

Inadequate water-stability and antibacterial activity limit the biomedical application of polyvinyl alcohol (PVA)-based membranes in moist environments. In this work, we propose a strategy to improve the water-stability of PVA membranes via metal complexation and heat treatment. We report a simple routine where the zirconium-based UiO-66-NH2 metal-organic frameworks (MOFs) are nucleated as a layer on the surface of PVA nanofibrous membranes (UiO-66-NH2@PVA NFMs). We find that the chemical modification of membranes increases their hydrophilicity and adds on mechanical support for the brittle UiO-66-NH2 MOFs. Additionally, we demonstrate the application of UiO-66-NH2 MOFs as drug carriers for antibacterial drug, levofloxacin (LV). The active drug component is preloaded during the one-step nucleation process. The obtained LV loaded UiO-66-NH2@PVA NFMs (LV@UiO-66-NH2@PVA) are shown to be bactericidal with the efficiency > 99.9% at 100 µg/mL against two bacterial species, Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Compared with the commercially available gauzes, the UiO-66-NH2@PVA and LV@UiO-66-NH2@PVA treatments will significantly improve the wound healing process. Animal studies show that the LV@UiO-66-NH2@PVA will effectively offer a safe alternative solution for the patients to protect against bacterial infections, demonstrating the potential application of MOF-based NFMs as wound dressing agents.


Assuntos
Estruturas Metalorgânicas , Nanofibras , Animais , Antibacterianos/farmacologia , Escherichia coli , Humanos , Álcool de Polivinil , Staphylococcus aureus , Água , Cicatrização , Zircônio
12.
J Colloid Interface Sci ; 596: 312-323, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33839356

RESUMO

The chronic wounds often hinder wound healing resulting from infection; thus, an ideal wound dressing should be able to maintain a healthy wound microenvironment. Herein, peptide modified nanofibers reinforced hydrogel has been designed by Schiff base dynamic crosslinking. The incorporation of the nanofibers into the hydrogel extremely enhances the stability and mechanical strength of the hydrogel. Taking advantage of the feature, the reinforced hydrogel can restore its original shape while suffering the various external forces on the hydrogel-covered irregular shape wounds. The peptide modified nanofibers reinforced hydrogel (NFRH) not only possesses injectable and self-healing properties, but also inherent antibacterial and hemostatic properties, which can eradicate the bacterial biofilms and induce blood cells and platelets aggregation and finally accelerate the chronic wound healing process. The peptide modified nanofibers reinforced hydrogel has enormous potential to be novel dressing for chronic wounds healing clinically.


Assuntos
Hemostáticos , Nanofibras , Antibacterianos/farmacologia , Hidrogéis , Cicatrização
13.
Int J Mol Sci ; 21(18)2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32906715

RESUMO

Coating a cationic antibacterial layer on the surface of cotton fabric is an effective strategy to provide it with excellent antibacterial properties and to protect humans from bacterial cross-infection. However, washing with anionic detergent will inactivate the cationic antibacterial coating. Although this problem can be solved by increasing the amount of cationic antibacterial coating, excessive cationic antibacterial coating reduces the drapability of cotton fabric and affects the comfort of wearing it. In this study, a coordinated antibacterial coating strategy based on quaternary ammonium salt and a halogenated amine compound was designed. The results show that the antibacterial effect of the modified cotton fabric was significantly improved. In addition, after mechanically washing the fabric 50 times in the presence of anionic detergent, the antibacterial effect against Staphylococcus aureus and Escherichia coli was still more than 95%. Furthermore, the softness of the obtained cotton fabric showed little change compared with the untreated cotton fabric. This easy-to-implement and cost-effective approach, combined with the cationic contact and the release effect of antibacterial agents, can endow cotton textiles with durable antibacterial properties and excellent wearability.

14.
Carbohydr Polym ; 239: 116250, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32414442

RESUMO

Although traditional alkaline (TAL) process for ramie degumming is commonly used in the industry, it causes severe environmental concerns. In this work, an emerging organic solvent degumming process utilizing FeCl3 catalyst (FeCl3-OS) was developed in one step. The influences of FeCl3-OS system on fiber properties (e.g. residual gum content, tenacity, degree of polymerization (DP), etc.) were evaluated, and the recyclability of degumming solution was also studied. The results indicated that ramie fiber could be isolated with FeCl3-OS treatment (FeCl3 1.0 %, 200 ℃, 121 min), and the tenacity and residual gum content of refined fibers were 7.9 cN/dtex and 3.88 %, respectively. Fibers treated in FeCl3-OS system were endowed better moisture sorption (9.2 %) and higher yield (75.2 %) compared with that in TAL system. Moreover, fibers with five cycles' treatment possessed outstanding performances, that was 4.44 cN/dtex of tenacity and 4.33 % of residual gum content, which fulfilled the requirements of the spinning process.

15.
J Colloid Interface Sci ; 576: 302-312, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32447020

RESUMO

The current water treatment technology is still based on low energy efficient processes due to the complex composition of wastewater. To achieve high energy efficiency, many micro-porous materials with complex functional groups have been fabricated because of their high pollutant adsorption capabilities. In this work, antibacterial ß-cyclodextrin-based nanoparticles (E-ß-CDN) were prepared via one-pot method to explore their adsorption performance to pollutants in wastewater. The resulting nanoparticles exhibited superfast adsorption kinetics to pollutants with removal efficiency of over 95% within 10 s. The nanoparticles also presented broad-spectrum adsorption to organic pollutants and heavy metal ions, and their maximum adsorption capacity was 3289.6 mg g-1 towards methyl orange (MO) and 970.8 mg g-1 towards Pb(II), much higher than that of many other adsorbents. Easy cyclic adsorption-desorption was another distinguishing feature of the nanoparticles, whose removal efficiency to these pollutants hardly varied after 10 cycles of regeneration. Interestingly, the resulting nanoparticles showed prominent antibacterial activity of 99.99% bacterial inhibitive rate against both gram-negative bacteria Escherichia coli (E. coli) and gram-positive bacteria Staphylococcus aureus (S. aureus). These results suggest that the resulting nanoparticles have great potential in the purification of the wastewater.


Assuntos
Poluentes Ambientais , Nanopartículas , Poluentes Químicos da Água , Purificação da Água , beta-Ciclodextrinas , Adsorção , Antibacterianos/farmacologia , Escherichia coli , Cinética , Staphylococcus aureus , Poluentes Químicos da Água/análise
16.
Biomater Sci ; 7(12): 5404-5413, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31633702

RESUMO

A polyester hernia patch has received extensive attention in mesh hernia repair. However, it is still a challenge to develop polyester-based implants with inherent antibacterial properties due to the lack of active functional groups. In this study, poly(butylene succinate-co-butylene aspartate) (PBSA) was constructed by introducing aspartic acid on a polybutylene succinate (PBS) polyester chain (PBSA). Antimicrobial treatment was conducted by grafting levofloxacin (Lv) on the surface of a PBSA polymer (PBSA-g-Lv). In vitro antibacterial test results showed that PBSA-g-Lv had sufficient local antimicrobiotic effects against Staphylococcus aureus and Escherichia coli and no side effect on L929 cells was observed. Furthermore, almost no change was observed in the thermodynamic properties of PBS and PBSA; in vivo tests demonstrated that this contact-active antibacterial PBSA-g-Lv nanofiber is a promising material to fulfill the dual functions of promoting tissue regeneration and preventing bacterial infection. The presented data confirmed that an antibiotic surface modification of PBSA polyesters was expected to be used as hernia repair materials.


Assuntos
Antibacterianos/administração & dosagem , Ácido Aspártico/química , Levofloxacino/administração & dosagem , Poliésteres/síntese química , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular , Modelos Animais de Doenças , Escherichia coli/efeitos dos fármacos , Herniorrafia , Interações Hidrofóbicas e Hidrofílicas , Levofloxacino/química , Levofloxacino/farmacologia , Camundongos , Poliésteres/química , Staphylococcus aureus/efeitos dos fármacos
17.
ACS Appl Mater Interfaces ; 11(47): 44682-44690, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31596064

RESUMO

One of the fundamental properties of natural systems is their water transport ability, and living systems have efficient moisture management features. Here, a unique structure, inspired by the water transfer behavior in trees, was designed for one-dimensional (1D) fiber assemblies. In this 1D fiber assembly structure, a differential capillary effect enabling rapid water transfer at the interface between traditional cotton fibers and electrospun nanofibers was explored. A tree-like structure yarn was constructed successfully by novel electrospinning technology, and the effect was quantitatively controlled by precisely regulating the fibers' wettability. Fabrics based on these tree-like core-spun yarns possessed advanced moisture-wicking performance, a high one-way transport index (R) of 1034.5%, and a desirable overall moisture management capability of 0.88, which are over two times higher than those of conventional fabrics. This moisture-wicking regime endowed these 1D fiber assemblies with unique water transfer channels, providing a new strategy for moisture-heat transmission, microfluidics, and biosensor applications.

18.
Nanoscale ; 11(40): 18653-18661, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31584597

RESUMO

In this work, ß-cyclodextrin (ß-CD) based hollow nanoparticles (denoted as ß-CDHN) with abundant active sites and high specific surface area were first fabricated via a facile one-step method. The ß-CDHN presented a maximum adsorption capacity of 2080.35, 427.35 and 120.48 mg g-1 towards the cationic dye methylene blue (MB), heavy metal ions (Pb2+) and bisphenol A (BPA), respectively, much higher than those of many other adsorbents. Furthermore, ß-CDHN also exhibited fast adsorption kinetics towards these pollutants with adsorption rate constants 6 to 200 times higher than those of activated carbon and other ß-CD-based adsorbents, meaning the former can remove these pollutants at a much faster adsorption rate than the latter adsorbents. More importantly, the removal efficiency of these pollutants on ß-CDHN almost remained stable after 10 regeneration cycles with favorable recyclability. The prepared ß-CDHN show great potential in practical applications due to their low costs and high efficiency in the treatment of organic and inorganic pollutants from wastewater.

19.
J Colloid Interface Sci ; 540: 634-646, 2019 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-30690388

RESUMO

Bacterial infection is one of the most significant complications worldwide and has been one of the main factors of morbidity and mortality for the chronic wounds. Considering the negative charged feature of bacterial pathogens, a positive charged poly(ester amide) (PEA) micellar system based on lysine, arginine and phenylalanine is developed. In this study, a serials of PEA random copolymers can be obtained by altering the sorts of amino acids and feed ratio, and the self-assembled PEA micelles with an average diameter ranging from 150 to 200 nm exhibit the integrated properties of excellent biocompatibility and enzymatic biodegradation. More interesting, the degraded random block micelles can reassemble into smaller sized micelles with the diameter less than 20 nm which have promising applications in drug delivery. The PEA micellar nanocarriers display an intrinsic antibacterial property due to the pendant groups of lysine and arginine based moieties and this killing capacity can be enhanced by grafting levofloxacin without losing the original performance. The in vitro antibacterial evaluation proves all of the micelles display a concentration dependent efficiency of killing bacteria (up to 99.99%). The in vivo Staphylococcus aureus induced infection model demonstrates that the micelles are effective in killing the bacteria and infection treatment. The successful synthesis of the biocompatible and biodegradable amino acid based micellar nanocarriers may provide new insights into the development of biomedical materials for antibacterial applications and drug delivery.


Assuntos
Aminoácidos/química , Antibacterianos/administração & dosagem , Portadores de Fármacos/química , Levofloxacino/administração & dosagem , Nylons/química , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Liberação Controlada de Fármacos , Esterificação , Células HeLa , Humanos , Levofloxacino/farmacologia , Levofloxacino/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Micelas
20.
RSC Adv ; 9(14): 7620-7628, 2019 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35521176

RESUMO

A facile route of 'copolymerization/blending' was proposed to fabricate silicon/nitrogen synergistically reinforced flame-retardant PA6 nanocomposites with simultaneously improved anti-dripping and mechanical properties. Firstly, a persistently inherent flame-retardant PA6 (FR-PA6), with 1,3-bis(3-aminopropyl)tetramethyl disiloxane (MSDS), was synthesized via controllable amidation and a polycondensation reaction. Melamine cyanurate (MCA) nanoparticles as a 'gas phase' synergistic agent were then added into FR-PA6 to further improve its flame retardancy. The primarily obtained FR-PA6 could be extinguished after a few melt droplets dropped as ignited, and passed the V-2 rating with enhanced mechanical properties, while PA6 had no rating (NR). The prepared FR-PA6/MCA nanocomposites could attain a limiting oxygen index (LOI) value of 32.7%, and passed the V-0 level with only 1 melting droplet with similar mechanical properties to PA6. Accordingly, the special 'condensed-gas phase' synergistic flame-retardant mechanism of FR-PA6/MCA nanocomposites was proposed through studying the residues and pyrolysis volatiles. This work provided a facile route as a model for developing functional PA6 for diverse engineering applications.

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