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1.
Molecules ; 29(11)2024 May 28.
Article in English | MEDLINE | ID: mdl-38893415

ABSTRACT

The synergistic effect of drug and gene delivery is expected to significantly improve cancer therapy. However, it is still challenging to design suitable nanocarriers that are able to load simultaneously anticancer drugs and nucleic acids due to their different physico-chemical properties. In the present work, an amphiphilic block copolymer comprising a biocompatible poly(ethylene glycol) (PEG) block and a multi-alkyne-functional biodegradable polycarbonate (PC) block was modified with a number of poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) side chains applying the highly efficient azide-alkyne "click" chemistry reaction. The resulting cationic amphiphilic copolymer with block and graft architecture (MPEG-b-(PC-g-PDMAEMA)) self-associated in aqueous media into nanosized micelles which were loaded with the antioxidant, anti-inflammatory, and anticancer drug quercetin. The drug-loaded nanoparticles were further used to form micelleplexes in aqueous media through electrostatic interactions with DNA. The obtained nanoaggregates-empty and drug-loaded micelles as well as the micelleplexes intended for simultaneous DNA and drug codelivery-were physico-chemically characterized. Additionally, initial in vitro evaluations were performed, indicating the potential application of the novel polymer nanocarriers as drug delivery systems.


Subject(s)
DNA , Drug Carriers , Methacrylates , Micelles , Nylons , Quercetin , Quercetin/chemistry , Quercetin/pharmacology , Methacrylates/chemistry , DNA/chemistry , Nylons/chemistry , Drug Carriers/chemistry , Humans , Polyethylene Glycols/chemistry , Nanoparticles/chemistry , Polymers/chemistry
2.
Environ Sci Pollut Res Int ; 31(27): 39454-39480, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38822176

ABSTRACT

The forward osmosis (FO) process has recently gained significant interest in treating wastewater, brackish/seawater and concentrating feedstocks for various operations, including desalination. The study investigates the effect of different synthesis conditions of the polyamide-based thin-film composite (TFC) FO membranes on the membranes' final performance. Taguchi statistical analyses were used to fabricate and optimize the polyamide TFC FO membrane. The process parameters as factors were the amount of polyethersulfone (PES), polyethylene glycol 400 (PEG-400), polyvinyl pyrrolidone (PVP), m-phenylenediamine (MPD), and trimesoyl chloride (TMC), and TMC reaction-time (RT). The Taguchi method was adopted to investigate the optimal conditions and the significance of individual factors using an L16 (45) orthogonal array. Another Taguchi analysis (Taguchi 2) was adopted to investigate the influence of other important parameters like optimal conditions for MPD, TMC, and TMC reaction-time factors using an L9 (33) orthogonal array. Confirmation tests validated a maximum water flux of 46.4 ± 2.32 L/m2·h with a specific combination of control factors for membrane synthesis: PES/PEG/PVP/MPD/TMC/TMC RT-16/7/0.5/1/0.05/30. These tests demonstrated a high-water flux of 7.05 ± 0.35 L/m2·h when exposed to industrial wastewater (secondary effluent) as the feed solution (FS) and fertilizer as the draw solution (DS) in the FO process. The R2 values were more than 90%. The experimental validation confirmed the models' predictive ability with different FSs, including industrial wastewater.


Subject(s)
Membranes, Artificial , Nylons , Osmosis , Wastewater , Water Purification , Wastewater/chemistry , Nylons/chemistry , Water Purification/methods , Waste Disposal, Fluid/methods , Polymers/chemistry
3.
J Colloid Interface Sci ; 670: 486-498, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-38772264

ABSTRACT

Establishing a physical barrier between the peritoneum and the cecum is an effective method to reduce the risk of postoperative abdominal adhesions. Meloxicam (MX), a nonsteroidal anti-inflammatory drug has also been applied to prevent postoperative adhesions. However, its poor water solubility has led to low bioavailability. Herein, we developed an injectable hydrogel as a barrier and drug carrier for simultaneous postoperative adhesion prevention and treatment. A third-generation polyamide-amine dendrimer (G3) was exploited to dynamically combine with MX to increase the solubility and the bioavailability. The formed G3@MX was further used to crosslink with poly-γ-glutamic acid (γ-PGA) to prepare a hydrogel (GP@MX hydrogel) through the amide bonding. In vitro and in vivo experiments evidenced that the hydrogel had good biosafety and biodegradability. More importantly, the prepared hydrogel could control the release of MX, and the released MX is able to inhibit inflammatory responses and balance the fibrinolytic system in the injury tissues in vivo. The tunable rheological and mechanical properties (compressive moduli: from âˆ¼ 57.31 kPa to âˆ¼ 98.68 kPa;) and high anti-oxidant capacity (total free radical scavenging rate of âˆ¼ 94.56 %), in conjunction with their syringeability and biocompatibility, indicate possible opportunities for the development of advanced hydrogels for postoperative tissue adhesions management.


Subject(s)
Dendrimers , Hydrogels , Meloxicam , Nylons , Polyglutamic Acid , Hydrogels/chemistry , Hydrogels/pharmacology , Animals , Polyglutamic Acid/chemistry , Polyglutamic Acid/pharmacology , Polyglutamic Acid/analogs & derivatives , Nylons/chemistry , Tissue Adhesions/prevention & control , Dendrimers/chemistry , Dendrimers/pharmacology , Meloxicam/chemistry , Meloxicam/pharmacology , Meloxicam/administration & dosage , Mice , Inflammation/prevention & control , Inflammation/drug therapy , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Rats , Rats, Sprague-Dawley , Fibrinolysis/drug effects , Postoperative Complications/prevention & control , Particle Size , Injections , Drug Carriers/chemistry
4.
Int J Biol Macromol ; 270(Pt 2): 132064, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38719012

ABSTRACT

The extensive use of fossil based materials has caused serious pollution problems, the full utilization of biomass resources to prepare high value-added new materials is of great significance for the environmental protection and sustainable social development. For this purpose, this study explored the preparation process and molecular dynamics simulation of cellulose fluorescent materials. Firstly, bacterial cellulose was dissolved in a solution of NaOH and urea at low temperature, followed by a solution blending and hot pressing with hyperbranched polyamide. It was found that the addition of hyperbranched polyamide could effectively filled in the internal pores of cellulose hydrogel, thereby enhancing the fluorescence effects and tensile properties, especially the elongation at break of cellulose materials. The optimal amount of hyperbranched polyamide added was 5 wt%. Molecular dynamics simulation showed that the hydrogen bonds and interaction with cellulose increased as the concentration of hyperbranched polyamide increased.


Subject(s)
Cellulose , Molecular Dynamics Simulation , Cellulose/chemistry , Nylons/chemistry , Fluorescent Dyes/chemistry , Hydrogen Bonding , Tensile Strength , Hydrogels/chemistry
5.
Aquat Toxicol ; 271: 106934, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38728926

ABSTRACT

Microplastics (MP) and antibiotics coexist in the environment and their combined exposure represents a source of increasing concern. MP may act as carriers of antibiotics because of their sorption capacity. Knowledge of the interactions between them may help improve understanding of their migration and transformation. In this work, the adsorption behaviour of a group of sulfonamides and their acetylated metabolites on different sizes of polyamide (PA) and polystyrene (PS) MP were investigated and compared. Sulfonamides were adsorbed on both MP (qmax up to 0.699 and 0.184 mg/g, for PA and PS, respectively) fitting to a linear isotherm model (R2 > 0.835). A low particle size and an acidic and salinity medium significantly enhances the adsorption capacity of sulfonamides (i.e. removal of sulfamethoxazole increased from 8 % onto 3 mm PA pellets to 80 % onto 50 mm of PA pellets). According to characterization results, adsorption mechanism is explained by pore filling and hydrogen bonds (for PA) and hydrophobic interactions (for PS). After adsorption, surface area was increased in both MP as result of a potential ageing of the particles and the intensity of XRD peaks was higher denoting a MP structure more amorphized. Metabolites were adsorbed more efficiently than their parent compounds on PS while the opposite effect was observed on PA explained by the acetylation of the amine group and, subsequently the reduction of hydrogen bond interactions. Although the dissolved organic matter inhibits sulfonamides adsorption, removal up to 65.2 % in effluent wastewater and up to 72.1 % in surface water were observed in experiments using real matrices denoting the role of MP as vectors of sulfonamide antibiotics in aquatic media.


Subject(s)
Anti-Bacterial Agents , Microplastics , Nylons , Polystyrenes , Sulfonamides , Water Pollutants, Chemical , Water Pollutants, Chemical/chemistry , Polystyrenes/chemistry , Adsorption , Anti-Bacterial Agents/chemistry , Sulfonamides/chemistry , Nylons/chemistry , Microplastics/chemistry , Particle Size
6.
ACS Biomater Sci Eng ; 10(6): 4073-4084, 2024 06 10.
Article in English | MEDLINE | ID: mdl-38752228

ABSTRACT

Due to the decomposition temperature of Polyamide 66 (PA66) in the environment is close to its thermoforming temperature, it is difficult to construct porous scaffolds of PA66/nanohydroxyapatite (PA66/HAp) by fused deposition modeling (FDM) three-dimensional (3D) printing. In this study, we demonstrated for the first time a method for 3D printing PA66/HAp composites at room temperature, prepared PA66/HAp printing ink using a mixed solvent of formic acid/dichloromethane (FA/DCM), and constructed a series of composite scaffolds with varying HAp content. This printing system can print composite materials with a high HAp content of 60 wt %, which is close to the mineral content in natural bone. The physicochemical evaluation presented that the hydroxyapatite was uniformly distributed within the PA66 matrix, and the PA66/HAp composite scaffold with 30 wt % HAp content exhibited optimal mechanical properties and printability. The results of in vitro cell culture experiments indicated that the incorporation of HAp into the PA66 matrix significantly improved the cell adhesion, proliferation, and osteogenic differentiation of bone marrow stromal cells (BMSCs) cultured on the scaffold. In vivo animal experiments suggested that the PA66/HAp composite material with 30 wt % HAp content had the best structural maintenance and osteogenic performance. The three-dimensional PA66/HAp composite scaffold prepared by low temperature printing in the current study holds great potential for the repair of large-area bone defects.


Subject(s)
Durapatite , Mesenchymal Stem Cells , Nylons , Printing, Three-Dimensional , Tissue Scaffolds , Durapatite/chemistry , Tissue Scaffolds/chemistry , Nylons/chemistry , Animals , Mesenchymal Stem Cells/cytology , Mesenchymal Stem Cells/drug effects , Bone Regeneration/drug effects , Osteogenesis/drug effects , Tissue Engineering/methods , Cell Proliferation/drug effects , Cell Differentiation/drug effects , Temperature , Cell Adhesion
7.
Chemosphere ; 360: 142437, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38797208

ABSTRACT

The construction and modification of a Graphene Oxide (GO) membrane, incorporating polyvinyl alcohol (PVA) cross-linked with maleic acid (MA) and supported by a nylon membrane, have been successfully completed. Systematic variations in PVA and MA concentrations were conducted to achieve membranes with favorable characteristics, stability, and excellent desalination performance. Optimization studies utilizing the Central Composite Design (CCD) revealed that the most optimal desalination results were obtained with 10 mL of PVA (0.1 mg mL-1) and 0.9 M of MA (GO-MA0.9-PVA10/Nylon membrane). Experimental findings demonstrated that the inclusion of PVA and MA resulted in an increased interlayer distance of GO and enhanced membrane stability. The addition of PVA increases GO membrane hydrophilicity, while the addition of MA reduces membrane hydrophilicity. The GO-MA0.9-PVA10/Nylon membrane exhibited the highest desalination performance, boasting a rejection value exceeding >99.9% and a permeance of 18.76 kg m-2.h-1 under 1% NaCl feed at a temperature of 50 °C. This membrane demonstrated consistent desalination performance stability over an extended period of up to 70 h. Moreover, it exhibited durability through 8 cycles of 24-h usage with washing treatment. In conclusion, the GO-MA0.9-PVA10/Nylon membrane is strongly recommended for practical applications, outperforming other membrane options based on the comprehensive evaluation of its stability and desalination efficiency.


Subject(s)
Graphite , Membranes, Artificial , Polyvinyl Alcohol , Sodium Chloride , Water Purification , Graphite/chemistry , Polyvinyl Alcohol/chemistry , Water Purification/methods , Sodium Chloride/chemistry , Filtration/methods , Maleates/chemistry , Salinity , Hydrophobic and Hydrophilic Interactions , Nylons/chemistry
8.
ACS Appl Mater Interfaces ; 16(19): 25304-25316, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38654450

ABSTRACT

Poly(vinyl alcohol) (PVA) hydrogels are water-rich, three-dimensional (3D) network materials that are similar to the tissue structure of living organisms. This feature gives hydrogels a wide range of potential applications, including drug delivery systems, articular cartilage regeneration, and tissue engineering. Due to the large amount of water contained in hydrogels, achieving hydrogels with comprehensive properties remains a major challenge, especially for isotropic hydrogels. This study innovatively prepares a multiscale-reinforced PVA hydrogel from molecular-level coupling to nanoscale enhancement by chemically cross-linking poly(vinylpyrrolidone) (PVP) and in situ assembled aromatic polyamide nanofibers (ANFs). The optimized ANFs-PVA-PVP (APP) hydrogels have a tensile strength of ≈9.7 MPa, an elongation at break of ≈585%, a toughness of ≈31.84 MJ/m3, a compressive strength of ≈10.6 MPa, and a high-water content of ≈80%. It is excellent among all reported PVA hydrogels and even comparable to some anisotropic hydrogels. System characterizations show that those performances are attributed to the particular multiscale load-bearing structure and multiple interactions between ANFs and PVA. Moreover, APP hydrogels exhibit excellent biocompatibility and a low friction coefficient (≈0.4). These valuable performances pave the way for broad potential in many advanced applications such as biological tissue replacement, flexible wearable devices, electronic skin, and in vivo sensors.


Subject(s)
Biocompatible Materials , Hydrogels , Nanofibers , Polyvinyl Alcohol , Povidone , Nanofibers/chemistry , Polyvinyl Alcohol/chemistry , Hydrogels/chemistry , Povidone/chemistry , Biocompatible Materials/chemistry , Animals , Mice , Nylons/chemistry , Tensile Strength , Materials Testing , Compressive Strength
9.
Environ Sci Pollut Res Int ; 31(22): 32637-32648, 2024 May.
Article in English | MEDLINE | ID: mdl-38658510

ABSTRACT

The production of antibacterial colored textiles using nanomaterials (NMs) has become an ideal goal from both a research and industrial perspective. In this study, the clean synthesis and characterization of silver nanoparticles (AgNPs) on polyamide fabrics were performed using mullein extract for the first time. Natural dyes were extracted from mullein leaves using an ultrasonic method, with an optimal amount of 15 g/L. The synthesized AgNPs in different ratios of mullein extract and Ag ions were analyzed (using UV-visible spectroscopy) and dynamic light scattering (DLS). It was found that AgNPs synthesized with a ratio of 1:4 of mullein extract: to Ag ions had a diameter of 85 nm. The active site groups of the synthesized AgNPs were characterized using Fourier transform infrared spectroscopy (FT-IR). Nylon fabrics dyed with different ratios of mullein extract and Ag ions exhibited acceptable color strength values (K/S) of 3.36. Furthermore, the reduction in bacterial growth for dyed fabrics improved with an increase in the ratio of Ag ions, with a 100% reduction observed for a sample dyed with mullein extract: Ag ions at a ratio of 1:4. Overall, this method offers a simple, low-cost, and compatible process with environment without the consumption of any chemicals to producing nylon with acceptable antibacterial and dyeing properties.


Subject(s)
Anti-Bacterial Agents , Metal Nanoparticles , Nylons , Silver , Textiles , Silver/chemistry , Metal Nanoparticles/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Nylons/chemistry , Colorimetry , Plant Extracts/chemistry , Spectroscopy, Fourier Transform Infrared , Coloring Agents/chemistry
10.
Environ Sci Technol ; 58(21): 9416-9426, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38662937

ABSTRACT

The polyamide (PA) nanofiltration (NF) membrane has the potential to remove endocrine-disrupting compounds (EDCs) from water and wastewater to prevent risks to both the aquatic ecosystem and human health. However, our understanding of the EDC removal-water permeance trade-off by the PA NF membrane is still limited, although the salt selectivity-water permeance trade-off has been well illustrated. This constrains the precise design of a high-performance membrane for removing EDCs. In this study, we manipulated the PA nanostructures of NF membranes by altering piperazine (PIP) monomer concentrations during the interfacial polymerization (IP) process. The upper bound coefficient for EDC selectivity-water permeance was demonstrated to be more than two magnitudes lower than that for salt selectivity-water permeance. Such variations were derived from the different membrane-solute interactions, in which the water/EDC selectivity was determined by the combined effects of steric exclusion and the hydrophobic interaction, while the electrostatic interaction and steric exclusion played crucial roles in water/salt selectivity. We further highlighted the role of the pore number and residual groups during the transport of EDC molecules across the PA membrane via molecular dynamics (MD) simulations. Fewer pores decreased the transport channels, and the existence of residual groups might cause steric hindrance and dynamic disturbance to EDC transport inside the membrane. This study elucidated the trade-off phenomenon and mechanisms between EDC selectivity and water permeance, providing a theoretical reference for the precise design of PA NF membranes for effective removal of EDCs in water reuse.


Subject(s)
Endocrine Disruptors , Filtration , Membranes, Artificial , Nylons , Water Pollutants, Chemical , Endocrine Disruptors/chemistry , Nylons/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Water/chemistry , Nanostructures/chemistry
11.
Angew Chem Int Ed Engl ; 63(23): e202402509, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38588046

ABSTRACT

Membranes are important in the pharmaceutical industry for the separation of antibiotics and salts. However, its widespread adoption has been hindered by limited control of the membrane microstructure (pore architecture and free-volume elements), separation threshold, scalability, and operational stability. In this study, 4,4',4'',4'''-methanetetrayltetrakis(benzene-1,2-diamine) (MTLB) as prepared as a molecular building block for fabricating thin-film composite membranes (TFCMs) via interfacial polymerization. The relatively large molecular size and rigid molecular structure of MTLB, along with its non-coplanar and distorted conformation, produced thin and defect-free selective layers (~27 nm) with ideal microporosities for antibiotic desalination. These structural advantages yielded an unprecedented high performance with a water permeance of 45.2 L m-2 h-1 bar-1 and efficient antibiotic desalination (NaCl/adriamycin selectivity of 422). We demonstrated the feasibility of the industrial scaling of the membrane into a spiral-wound module (with an effective area of 2.0 m2). This module exhibited long-term stability and performance that surpassed those of state-of-the-art membranes used for antibiotic desalination. This study provides a scientific reference for the development of high-performance TFCMs for water purification and desalination in the pharmaceutical industry.


Subject(s)
Anti-Bacterial Agents , Membranes, Artificial , Nylons , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/isolation & purification , Nylons/chemistry , Water Purification/methods , Filtration/methods , Permeability
13.
Environ Sci Technol ; 58(14): 6435-6443, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38551393

ABSTRACT

Nanovoids within a polyamide layer play an important role in the separation performance of thin-film composite (TFC) reverse osmosis (RO) membranes. To form more extensive nanovoids for enhanced performance, one commonly used method is to incorporate sacrificial nanofillers in the polyamide layer during the exothermic interfacial polymerization (IP) reaction, followed by some post-etching processes. However, these post-treatments could harm the membrane integrity, thereby leading to reduced selectivity. In this study, we applied in situ self-etchable sacrificial nanofillers by taking advantage of the strong acid and heat generated in IP. CaCO3 nanoparticles (nCaCO3) were used as the model nanofillers, which can be in situ etched by reacting with H+ to leave void nanostructures behind. This reaction can further degas CO2 nanobubbles assisted by heat in IP to form more nanovoids in the polyamide layer. These nanovoids can facilitate water transport by enlarging the effective surface filtration area of the polyamide and reducing hydraulic resistance to significantly enhance water permeance. The correlations between the nanovoid properties and membrane performance were systematically analyzed. We further demonstrate that the nCaCO3-tailored membrane can improve membrane antifouling propensity and rejections to boron and As(III) compared with the control. This study investigated a novel strategy of applying self-etchable gas precursors to engrave the polyamide layer for enhanced membrane performance, which provides new insights into the design and synthesis of TFC membranes.


Subject(s)
Biofouling , Nanoparticles , Osmosis , Nylons/chemistry , Engraving and Engravings , Membranes, Artificial , Water/chemistry
14.
Environ Sci Technol ; 58(11): 5174-5185, 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-38451543

ABSTRACT

Nanofiltration (NF) has the potential to achieve precise ion-ion separation at the subnanometer scale, which is necessary for resource recovery and a circular water economy. Fabricating NF membranes for selective ion separation is highly desirable but represents a substantial technical challenge. Dipole-dipole interaction is a mechanism of intermolecular attractions between polar molecules with a dipole moment due to uneven charge distribution, but such an interaction has not been leveraged to tune membrane structure and selectivity. Herein, we propose a novel strategy to achieve tunable surface charge of polyamide membrane by introducing polar solvent with a large dipole moment during interfacial polymerization, in which the dipole-dipole interaction with acyl chloride groups of trimesoyl chloride (TMC) can successfully intervene in the amidation reaction to alter the density of surface carboxyl groups in the polyamide selective layer. As a result, the prepared positively charged (PEI-TMC)-NH2 and negatively charged (PEI-TMC)-COOH composite membranes, which show similarly high water permeance, demonstrate highly selective separations of cations and anions in engineering applications, respectively. Our findings, for the first time, confirm that solvent-induced dipole-dipole interactions are able to alter the charge type and density of polyamide membranes and achieve tunable surface charge for selective and efficient ion separation.


Subject(s)
Chlorides , Nylons , Chlorides/chemistry , Nylons/chemistry , Membranes, Artificial , Solvents , Water
15.
Methods ; 225: 20-27, 2024 May.
Article in English | MEDLINE | ID: mdl-38471600

ABSTRACT

Aberrant gene expression underlies numerous human ailments. Hence, developing small molecules to target and remedy dysfunctional gene regulation has been a long-standing goal at the interface of chemistry and medicine. A major challenge for designing small molecule therapeutics aimed at targeting desired genomic loci is the minimization of widescale disruption of genomic functions. To address this challenge, we rationally design polyamide-based multi-functional molecules, i.e., Synthetic Genome Readers/Regulators (SynGRs), which, by design, target distinct sequences in the genome. Herein, we briefly review how SynGRs access chromatin-bound and chromatin-free genomic sites, then highlight the methods for the study of chromatin processes using SynGRs on positioned nucleosomes in vitro or disease-causing repressive genomic loci in vivo.


Subject(s)
Chromatin , Nucleosomes , Humans , Chromatin/genetics , Chromatin/metabolism , Nucleosomes/genetics , Nucleosomes/metabolism , Nylons/chemistry , Nylons/pharmacology , Gene Expression Regulation/drug effects , Animals , Chromatin Assembly and Disassembly/drug effects , Chromatin Assembly and Disassembly/genetics , Genomics/methods
16.
Int J Biol Macromol ; 267(Pt 1): 129256, 2024 May.
Article in English | MEDLINE | ID: mdl-38493823

ABSTRACT

In the present study, the commercially available three different fabrics cotton, nylon and cotton/nylon were modified by chitosan and silver nanoparticles using a crosslinker triethyl orthoformate (TEOF). Resulted cotton­silver (Ag-Cs-Cot), nylon­silver (Ag-Cs-Nyl) and cotton-nylon silver (Ag-Cs-Cot-Nyl) fabrics showed significant anti-bacterial activity even after 50 washing cycles. Silver nanoparticles were prepared by reducing silver nitrate through sodium borohydride at 0 °C. In FTIR spectra the peak at near 1650 cm-1 confirmed that TEOF mediated attachment of chitosan with fabrics (due to C=N) and the stretching of secondary amine near the 3375 cm-1 indicated the silver attachment to the amine group of the chitosan. In Scanning Electron Microscope (SEM) images smooth surfaces of fabrics without any damage by modification process were observed. The antibacterial activity was Analyzed by agar diffusion and broth dilution assays against Escherichia coli and Staphylococcus aureus bacterial strains and results showed 90% bacterial inhibition against E. coli and 89% bacterial inhibition against S. aureus. For testing the antibacterial durability, the modified fabrics were washed with non-ionic detergent (10g/l) for 15 minutes under aggressive stirring (100 rpm) at room temperature. The modified fabrics retained antibacterial activity over the 50 washing cycles. Finally, the commercial potential of cotton-silver fabric was evaluated by stitching it with the socks of football players and interestingly results showed that the modified fabric on the socks showed more than 90% bacterial inhibition as compared to the plain fabric after 70 minutes of playing activity.


Subject(s)
Anti-Bacterial Agents , Chitosan , Cotton Fiber , Escherichia coli , Metal Nanoparticles , Nylons , Silver , Staphylococcus aureus , Textiles , Chitosan/chemistry , Chitosan/pharmacology , Silver/chemistry , Silver/pharmacology , Metal Nanoparticles/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Nylons/chemistry , Escherichia coli/drug effects , Staphylococcus aureus/drug effects , Microbial Sensitivity Tests , Formates/chemistry
17.
Chemosphere ; 353: 141108, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38423147

ABSTRACT

Thin film composite (TFC) reverse osmosis (RO) membrane shows good promise for treating wastewater containing endocrine disrupting chemical (EDC) pollutants. The incorporation of functional materials with exceptional structural and physico-chemical properties offers opportunities for the membranes preparation with enhanced permselectivity and better antifouling properties. The present study aims to improve the EDC removal efficiency of TFC RO membrane using two-dimensional titania nanosheets (TNS). RO membrane was prepared by incorporating TNS in the dense layer of polyamide (PA) layer to form thin film nanocomposite (TFN) membrane. The TNS loading was varied and the influences on membrane morphology, surface hydrophilicity, surface charge, as well as water permeability and rejection of EDC were investigated. The results revealed that the inclusion of TNS in the membrane resulted in the increase of water permeability and EDC rejection. When treating the mixture of bisphenol A (BPA) and caffeine at 100 ppm feed concentration, the TFN membrane incorporated with 0.05% TNS achieved water permeability of 1.45 L/m2·h·bar, which was 38.6% higher than that of unmodified TFC membrane, while maintaining satisfactory rejection of >97%. The enhancement of water permeability for TFN membrane can be attributed to their hydrophilic surface and unique nanochannel structure created by the nanoscale interlayer spacing via staking of TiO2 nanosheets. Furthermore, the 0.05TFN membrane exhibited excellent fouling resistance towards BPA and caffeine pollutants with almost 100% flux recovery for three cycles of operations.


Subject(s)
Benzhydryl Compounds , Endocrine Disruptors , Environmental Pollutants , Phenols , Osmosis , Nylons/chemistry , Caffeine , Water/chemistry
18.
Adv Healthc Mater ; 13(15): e2304355, 2024 06.
Article in English | MEDLINE | ID: mdl-38387159

ABSTRACT

Amyloid beta-protein (AßAß) is a main hallmark of Alzheimer's disease (AD), and a low amount of Aß protein accumulation appears to be a potential marker for AD. Here, an electrochemical DNA biosensor based on polyamide/polyaniline carbon nanotubes (PA/PANI-CNTs) is developed with the aim of diagnosing AD early using a simple, low-cost, and accessible method to rapidly detect Aß42 in human blood. Electrospun PA nanofibers served as the skeleton for the successive in situ deposition of PANI and CNTs, which contribute both high conductivity and abundant binding sites for the Aß42 aptamers. After the aptamers are immobilized, this aptasensor exhibits precise and specific detection of Aß42 in human blood within only 4 min with an extremely fast response rate, lower detection limit, and excellent linear detection range. These findings make a significant contribution to advancing the development of serum-based detection techniques for Aß42, thereby paving the way for improved diagnostic capabilities in the field of AD.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Aptamers, Nucleotide , Biomarkers , Biosensing Techniques , Electrochemical Techniques , Nanofibers , Nanotubes, Carbon , Alzheimer Disease/diagnosis , Alzheimer Disease/metabolism , Alzheimer Disease/blood , Humans , Nanofibers/chemistry , Amyloid beta-Peptides/blood , Amyloid beta-Peptides/analysis , Amyloid beta-Peptides/metabolism , Biosensing Techniques/methods , Electrochemical Techniques/methods , Biomarkers/blood , Nanotubes, Carbon/chemistry , Aptamers, Nucleotide/chemistry , Aniline Compounds/chemistry , Limit of Detection , Peptide Fragments/chemistry , Peptide Fragments/blood , Nylons/chemistry
19.
Macromol Rapid Commun ; 45(3): e2300524, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37903330

ABSTRACT

Polyamides (PA) are among the most essential and versatile polymers due to their outstanding characteristics, for example, high chemical resistance and temperature stability. Furthermore, nature-derived monomers can introduce hard-to-synthesize structures into the PAs for unique polymer properties. Pinene, as one of the most abundant terpenes in nature and its presumable stability-giving bicyclic structure, is therefore highly promising. This work presents simple anionic ring-opening polymerizations of ß-pinene lactam (AROP) in-bulk and in solution. PAs with high molecular weights, suitable for further processing, are produced. Their good mechanical, thermal (Td s up to 440 °C), and transparent appearance render them promising high-performance biomaterials. In the following, the suitability of different initiators is discussed. Thereby, it is found that NaH is the most successful for in-bulk polymerization, with a degree of polymerization (DP) of about 322. For solution-AROP, iPrMgCl·LiCl is successfully used for the first time, achieving DPs up to about 163. The obtained PAs are also hot-pressed, and the dynamic mechanical properties are analyzed.


Subject(s)
Bicyclic Monoterpenes , Lactams , beta-Lactams , Lactams/chemistry , Nylons/chemistry , Molecular Weight , Polymers/chemistry , Forests , Polymerization
20.
J Pharmacol Sci ; 154(1): 1-8, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38081679

ABSTRACT

PURPOSE: The DNA recognition peptide compounds pyrrole-imidazole (PI) polyamides bind to the minor groove and can block the binding of transcription factors to target sequences. To develop more PI polyamides as potential treatments for fibrotic diseases, including chronic renal failure, we developed multifunctional PI polyamides that increase hepatocyte growth factor (HGF) and decrease transforming growth factor (TGF)-ß1. METHODS: We designed seven PI polyamides (HGF-1 to HGF-7) that bind to the chicken ovalbumin upstream promoter transcription factor-1 (COUP-TF1) binding site of the HGF promoter sequence. We selected PI polyamides that increase HGF and suppress TGF-ß1 in human dermal fibroblasts (HDFs). FINDINGS: Gel shift assays showed that HGF-2 and HGF-4 bound the appropriate dsDNAs. HGF-2 and HGF-4 significantly inhibited the TGF-ß1 mRNA expression in HDFs stimulated by phorbol 12-myristate 13-acetate. HGF-2 and HGF-4 significantly inhibited the TGF-ß1 protein expression in HDFs with siRNA targeting HGF, indicating that HGF-2 and HGF-4 directly inhibited the expression of TGF-ß1. CONCLUSION: The designed and synthetic HGF PI polyamides targeting the HGF promoter, which increased the expression of HGF and suppressed the expression of TGF-ß, will be a potential practical medicine for fibrotic diseases, including progressive renal diseases.


Subject(s)
Nylons , Transforming Growth Factor beta1 , Humans , Nylons/chemistry , Nylons/pharmacology , Hepatocyte Growth Factor , Transforming Growth Factor beta/genetics , Pyrroles/pharmacology , Pyrroles/chemistry , Imidazoles/pharmacology , Imidazoles/chemistry
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