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1.
Int J Biol Macromol ; : 136077, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39357707

RESUMO

Ulcerative colitis (UC) stands as a chronic inflammatory intestinal disease. This study aimed to explore a sustained-release strategy to alleviate DSS-induced colitis in mice using polyelectrolyte complexes (PECs) encapsulating an alkaloid, isoliensinine (ISO). The drug delivery platform, termed "Saloplastics (SAL)", was prepared by fabrication of PECs through the solid-liquid phase separation of sodium caseinate (SC) and ε-polylysine (EPL), followed by centrifugation to yield compact structures. Coarse-grained molecular dynamics simulations demonstrated that SAL had a nanorod-like structure formation between EPL and SC, which implied that the self-assembly of SAL is driven by hydrophobic aggregation and strong electrostatic attractions. A comprehensive evaluation of SAL was conducted, including characterizations of its physicochemical and biological properties. The results showed SAL had thermal plasticization properties and excellent swelling capacity as well as susceptibility to hydrolysis by pH and proteinase in simulated gastric fluid. Moreover, SAL displayed a porous morphology with high surface area for immobilizing organic molecules. ISO@SAL, formulated by ISO encapsulated in SAL, not only demonstrated high potency in alleviating DSS-induced colitis in mice, but also increased the dosing intervals from one day to three days. In conclusion, SAL is a biocompatible sustained-release oral drug delivery platform for gastrointestinal applications.

2.
Adv Healthc Mater ; : e2402340, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39352099

RESUMO

Tissue adhesives are used for various medical applications, including wound closure, bleeding control, and bone healing. Currently available options often show weak adhesion or cause adverse effects. Recently, there has been an increasing interest in complex coacervates as medical adhesives. Complex coacervates are formed by mixing oppositely charged macromolecules that associate and undergo liquid-liquid phase separation, in which the dense bottom phase is the complex coacervate. Complex coacervates are strong and often biocompatible, and show strong underwater adhesion. The properties of the resulting materials are tunable by intrinsic factors such as polymer chemistry, molecular weight, charge density, and topology of the macromolecules, as well as extrinsic factors such as temperature, pH, and salt concentration. Therefore, complex coacervates are interesting new candidates for medical adhesives. In this review, it is described how complex coacervates form and how different factors influence their behavior. Next, an overview of recent studies on complex coacervates in the context of medical adhesives is presented. The application of complex coacervates as hemostatic or embolic agents, skin or bone repair adhesives, and soft tissue sealants is discussed. Lastly, additional possibilities for utilizing these materials in the future are discussed.

3.
Macromol Rapid Commun ; : e2400573, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39311484

RESUMO

Cotton fabrics with the main constituent of cellulose, which is hydrophilic, bacterial infected, and flammable, are in urgent need of functionalization as a kind of widely applied material. To address these issues, in this work, modified polyelectrolyte complex (MPEC) coatings with polyethylenimine (PEI), polyphosphate (APP), and perfluorodecyltrichlorosilane modified PEI (PFTS-PEI) are prepared to construct multi-functionally gradient MPEC coatings on cotton fabrics. Stability and synergistic effects on hydrophobicity, antibacterial activity, and flame retardancy in this system have been studied. Notably, PFTS-PEI with fluorine and silicone elements are confirmed to provide hydrophobicity and durability for MPEC coatings, which not only has no negative effect on other functions but also makes some improvement in antibacterial activity. This MPEC-treated cotton fabric finally has an antibacterial rate against S. aureus and E. coli of 99.9% and 96.9%, limiting oxygen index of 28.5% and water contact angle of 118°, which can be almost maintained after 20 times washing. The modified PEC will provide an efficient strategy to achieve durable multi-functions on cellulose-based fabrics.

4.
Gels ; 10(9)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39330163

RESUMO

Excessive reservoir water poses significant challenges in the oil and gas industry by diminishing hydrocarbon recovery efficiency and generating environmental and economic complications. Conventional polymer flooding techniques, although beneficial, often prove inadequate under conditions of elevated temperature and salinity, highlighting the need for more resilient materials. In this research, two types of acrylamide-based preformed particle gels (PPGs) were synthesized, as follows: polyelectrolyte and polyampholyte. These PPGs were engineered to improve plugging efficiency and endure extreme reservoir environments. The polyelectrolyte gels were synthesized using acrylamide (AAm) and sodium acrylate (SA), while the polyampholyte gels incorporated AAm, AMPS, and APTAC, with crosslinking achieved through MBAA. The swelling properties, modulated by temperature, salinity, and pH, were evaluated using the Ritger-Peppas and Yavari-Azizian models. The mechanical characteristics and surface morphology of the gels were analyzed using SEM and BET techniques. In sand pack experiments designed to mimic high-permeability reservoirs, the inclusion of 0.5 wt.% of fine PPGs substantially reduced water permeability, outperforming traditional hydrogels. Notably, the polyampholyte PPGs demonstrated superior resilience and efficacy in plugging. However, the experiments were limited by the low test temperature (25 °C) and brine salinity (26.6 g/L). Future investigations will aim to apply these PPGs in high-temperature, fractured carbonate reservoirs.

5.
Polymers (Basel) ; 16(18)2024 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-39339134

RESUMO

This review comprehensively explores the multifunctional applications of pectins derived from food waste and by-products, emphasizing their role as versatile biomaterials in the medical-related sectors. Pectins, known for their polyelectrolytic nature and ability to form hydrogels, influence the chemical composition, sensory properties, and overall acceptability of food and pharmaceutical products. The study presents an in-depth analysis of molecular parameters and structural features of pectins, such as the degree of esterification (DE), monosaccharide composition, galacturonic acid (GalA) content, and relative amounts of homogalacturonan (HG) and rhamnogalacturonan I (RG-I), which are critical for their technofunctional properties and biological activity. Emphasis is placed on pectins obtained from various waste sources, including fruits, vegetables, herbs, and nuts. The review also highlights the importance of structure-function relationships, especially with respect to the interfacial properties and rheological behavior of pectin solutions and gels. Biological applications, including antioxidant, immunomodulatory, anticancer, and antimicrobial activities, are also discussed, positioning pectins as promising biomaterials for various functional and therapeutic applications. Recalled pectins can also support the growth of probiotic bacteria, thus increasing the health benefits of the final product. This detailed review highlights the potential of using pectins from food waste to develop advanced and sustainable biopolymer-based products.

6.
Biomaterials ; 314: 122848, 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39342917

RESUMO

Chronic wound healing often encounters challenges characterized by prolonged inflammation and impaired angiogenesis. While the immune response plays a pivotal role in orchestrating the intricate process of wound healing, excessive inflammation can hinder tissue repair. In this study, a bilayer alginate hydrogel system encapsulating polyelectrolyte complex nanoparticles (PCNs) loaded with anti-inflammatory cytokines and angiogenic growth factors is developed to address the challenges of chronic wound healing. The alginate hydrogel is designed using two distinct crosslinking methods to achieve differential degradation, thereby enabling precise spatial and temporal controlled release of PCNs. Initially, interleukin-10 (IL-10) is released to mitigate inflammation, while unsaturated PCNs bind and remove accumulated pro-inflammatory cytokines at the wound site. Subsequently, angiogenic growth factors, including vascular endothelial growth factor and platelet-derived growth factor, are released to promote vascularization and vessel maturation. Our results demonstrate that the bilayer hydrogel exhibits distinct degradation kinetics between the two layers, facilitating the staged release of multiple signaling molecules. In vitro experiments reveal that IL-10 can activate the Jak1/STAT3 pathway, thereby suppressing pro-inflammatory cytokines and chemokines while down-regulating inflammation-related genes. In vivo studies demonstrate that application of the hydrogel in chronic wounds using diabetic murine model promotes healing by positively modulating multiple integral reparative mechanisms. These include reducing inflammation, promoting macrophage polarization towards a pro-regenerative phenotype, enhancing keratinocyte migration, stimulating angiogenesis, and expediting wound closure. In conclusion, our hydrogel system effectively mitigates inflammatory responses and provides essential physiological cues by inducing a synergistic angiogenic effect, thus offering a promising approach for the treatment of chronic wounds.

7.
Molecules ; 29(17)2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39274865

RESUMO

The ionic association of Alcian Blue dye with poly(styrene sulfonate) in aqueous solutions was studied for analytical purposes. The quadruple-charged cationic dye, Alcian Blue, was found to form colloidal ionic associates with poly(styrene sulfonate) anions. When the amounts of opposite charges are nearly equal, the resulting ionic associates lose solubility and coagulate rapidly. This effect occurs within a narrow range of the ratio of poly(styrene sulfonate) to Alcian Blue. At the point of charge equivalence, the zeta potential of the resulting particles is zero, which facilitates flocculation. The resulting flocs enlarge to approximately 0.05-0.5 mm and precipitate rapidly. FTIR spectroscopy confirms that the precipitate contains both poly(styrene sulfonate) and Alcian Blue dye. Sedimentation kinetics was studied in detail using scanning turbidimetry. Due to the high molar absorbance of the Alcian Blue dye at 600 nm, the point of equimolar charge ratio was precisely determined by spectrophotometry. The complete precipitation of ionic associates occurs when the amount of poly(styrene sulfonate) ranges from 1.4 to 1.55 mmol per 1 g of Alcian Blue dye. Such a narrow coagulation range allows for the use of the studied effect for quantitative analysis. Both Alcian Blue dye and poly(styrene sulfonate) can be quantified if one of their concentrations is known.

8.
Int J Biol Macromol ; 279(Pt 3): 135314, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39236941

RESUMO

The composite of a polyelectrolyte combination of chitosan and phytic acid (CsPa) and its entrapped form in polyacrylamide (PAAmCsPa) were synthesized. The composites were characterized by a number of methods including ATR-FTIR, SEM-EDX, XRD and XPS. The adsorptive properties of CsPa and PAAmCsPa were analyzed and modelled for UO22+ and methylene blue (MB+). The results showed that the composites exhibited physico-chemical properties that were both inherited from the components as well as unique to them. The isotherms of UO22+ and MB+ were L-type Giles isotherms. The adsorption kinetics followed the pseudo-second-order model, in contrast to the Langmuir model, which predicts first-order kinetics for both species. According to the Weber-Morris model, the nature of the adsorption process was ion exchange and/or complex formation for both composites and ions. The thermodynamics showed that the adsorption process was endothermic (ΔH > 0), with increasing entropy (ΔS > 0) and spontaneous (ΔG < 0). The reusability tests of the composites for UO22+ adsorption showed that the composites were substantially reusable for 6 cycles. The composites were selective for UO22+ over MB+ ions, and UO22+ adsorption increased significantly when MB+ adsorbed composites were used. Reproducible measurements demonstrating the storability of the composites were obtained over a period of approximately one year.

9.
Int J Biol Macromol ; 279(Pt 3): 135318, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39236957

RESUMO

Polyester/cotton (T/C) blended fabrics are widely utilized in textile due to the dimensional stability and high elasticity provided by polyester, combined with the comfort and moisture absorption offered by cotton. However, simultaneously enhancing the flame retardancy and maintaining the physical properties of T/C blended fabrics for clothing and furniture applications remains a big challenge. This study introduces a bio-based flame-retardant coating using polyelectrolyte complexes (PEC) composed of ammonium vinyl phosphonate-grafted chitosan (AMVP-g-CS). The protonation degree of the PEC coating is controlled by adjusting the pH to solidify and stabilize the complex structure, preparing bio-based PEC flame retardant T/C blended fabric. Flame retardant analysis reveals that the coated fabrics achieved a limiting oxygen index of 30.5 % and a char length of 11 mm, indicating significantly improved flame retardancy. The combustible volatile substances are significantly reduced for the coated fabrics, achieving a gas-phase flame retardant effect, and forming an expansive char layer with thermal insulation and oxygen blocking properties. Importantly, physical analysis proves that the PEC deposition improved mechanical properties, satisfactory whiteness index and hand feeling of the fabrics. This work opens up a pragmatic and industrially feasible strategy for the development of CSs in the field of flame retardant coating.

10.
J Colloid Interface Sci ; 678(Pt A): 1012-1021, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39232474

RESUMO

HYPOTHESIS: Ethoxylated complex coacervate core micelles (C3Ms), formed by the electrostatic coacervation of a charge-neutral diblock copolymer and an oppositely charged homopolymer, exhibit morphology governed by molecular packing principles. Additionally, this morphology is temperature-dependent, leading to transitions similar to those observed in classical ethoxylated surfactant aggregates. EXPERIMENTS: To explore the thermal effects on the size and morphology of C3Ms, we employed dynamic light scattering (DLS), small-angle X-ray scattering (SAXS), and cryogenic transmission electron microscopy (cryo-TEM). These techniques were applied to C3Ms formed by copolymers with varying poly(ethylene oxide) (EO) lengths. FINDINGS: Increasing the temperature-induced a transition from spherical to elongated aggregates, contingent on the EO block length. This morphological transition in EO-containing C3Ms parallels the behavior of classical ethoxylated surfactant aggregates. Despite the fundamental differences between hydrophobically driven and electrostatic coacervate micelles, our findings suggest that similar molecular packing principles are universally applicable across both systems. Our results offer valuable insights for predicting the structural properties of these coacervate platforms, which is crucial for envisioning their future applications.

11.
Electrophoresis ; 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39287066

RESUMO

The characterization of the impurities of pharmaceutical monoclonal antibodies (mAbs) is crucial for their function and safety. Capillary zone electrophoresis (CZE) is one of the most efficient tools to separate charge variants of mAbs; however, peak characterization remains difficult, since the hereby used background electrolytes (BGEs) are not compatible with electrospray ionization-mass spectrometry (ESI-MS). Here, a method that allows the separation of intact mAb charge variants is presented using CZE-ESI-MS, combining a cationic capillary coating and an acidic BGE. Therefore, a successive multiple ionic-polymer layer coating was developed based on diethylaminoethyl-dextran-poly(sodium styrene sulfonate). This coating leads to a relatively low reversed electroosmotic flow (EOF) with an absolute mobility slightly higher than that of antibodies, enabling the separation of variants with slightly different mobilities. The potential of the coating is demonstrated using USP mAb003, where it was possible to separate C-terminal lysine variants from the main form, as well as several acidic variants and monoglycosylated mAb forms. The presented CZE-MS method can be applied to separate charge variants of a range of other antibodies such as infliximab, NISTmAB (Reference Material from the National Institute of Standards and Technology), adalimumab, and trastuzumab, demonstrating the general applicability for the separation of proteoforms of mAbs.

12.
Carbohydr Res ; 545: 109277, 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39299161

RESUMO

Interaction of chitosan and its derivatives with proteins of animal blood at blood pH relevant conditions is of a particular interest for construction of antimicrobial chitosan/protein-based drug delivery systems. In this work, the interaction of a series of N-reacetylated oligochitosans (RA-CHI) having Mw of 10-12 kDa and differing in the degree of acetylation (DA 19, 24, and 40 %) with bovine serum albumin (BSA) in alkalescent media is described in first. It is shown that RA-CHI forms soluble complexes with BSA in solutions with pH 7.4 and a low ionic strength. Light scattering study shows that soluble RA-CHI complexes have spherical form with the radius of about 100 nm. Circular dichroism, fluorescent spectroscopy, and micro-IR spectroscopy studies show that the secondary structure of BSA in soluble complexes remain intact. Isothermal titration calorimetry of RA-CHI with DA 24 % and BSA mixing in the buffers with different ionization heats reveals a significant contribution of electrostatic forces to the binding process and an additional ionization of chitosan due to the proton transfer from the buffer substance. An increase of ionic strength to the blood relevant value 0.15 M suppresses the binding. It is shown that application of RA-CHI with higher DA value leads to a decrease in the affinity of RA-CHI to BSA and an alteration of the interaction mechanism. The finding opens an opportunity to the application of N-reacetylated chitosan derivatives in the complex systems compatible with blood plasma proteins.

13.
Environ Monit Assess ; 196(10): 874, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39222246

RESUMO

The present study deals with the assessment of different physicochemical parameters (pH, electrical conductivity (E.C.), turbidity, total dissolved solids (TDS), and dissolved oxygen) in different surface water such as pond, river, and canal water in four different seasons, viz. March, June, September, and December 2023. The research endeavors to assess the impact of a cationic polyelectrolyte, specifically poly(diallyl dimethyl ammonium chloride) (PDADMAC), utilized as a coagulation aid in conjunction with lime for water treatment. Employing a conventional jar test apparatus, turbidity removal from diverse water samples is examined. Furthermore, the samples undergo characterization utilizing X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The study also conducts correlation analyses on various parameters such as electrical conductivity (EC), pH, total dissolved solids (TDS), turbidity of raw water, polyelectrolyte dosage, and percentage of turbidity removal across different water sources. Utilizing the Statistical Package for Social Science (SPSS) software, these analyses aim to establish robust relationships among initial turbidity, temperature, percentage of turbidity removal, dosage of coagulant aid, electrical conductivity, and total dissolved solids (TDS) in pond water, river water, and canal water. A strong positive correlation could be found between the percentage of turbidity removal and the value of initial turbidity of all surface water. However, a negative correlation could be observed between the polyelectrolyte dosage and raw water's turbidity. By elucidating these correlations, the study contributes to a deeper understanding of the effectiveness of PDADMAC and lime in water treatment processes across diverse environmental conditions. This research enhances our comprehension of surface water treatment methodologies and provides valuable insights for optimizing water treatment strategies to address the challenges posed by varying water sources and seasonal fluctuations.


Assuntos
Compostos de Cálcio , Óxidos , Compostos de Amônio Quaternário , Rios , Estações do Ano , Purificação da Água , Óxidos/química , Compostos de Cálcio/química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/análise , Rios/química , Purificação da Água/métodos , Polietilenos/química , Poluentes Químicos da Água/análise , Lagoas/química , Monitoramento Ambiental/métodos
14.
Carbohydr Polym ; 344: 122501, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39218540

RESUMO

Cellulose-based aerogel fibers are recognized as a promising candidate for wearable thermal insulation textiles due to their high porosity, extremely low thermal conductivity, and environmental friendliness. Unfortunately, their practical application in textiles is severely limited by their brittleness. Herein, a novel "long yarn-assisted interfacial polyelectrolyte complexation (YAIPC) spinning" technique is proposed to fabricate cellulose-based aerogel fibers with a unique core-shell structure. The as-prepared core-shell aerogel fibers show excellent thermal insulation performance (34.3 mW m-1 K-1) and robust mechanical strength (∼100 MPa, 31.5 MJ m-3), providing great potential as wearable thermal insulating materials. Accordingly, our research would open a new avenue for designing and constructing wearable aerogel fibers and textiles.

15.
Angew Chem Int Ed Engl ; : e202412754, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39219249

RESUMO

Acidic CO2 electrolysis offers a promising strategy to achieve high carbon utilization and high energy efficiency. However, challenges remain in suppressing the competitive hydrogen evolution reaction (HER) and improving product selectivity. High concentrations of potassium ions (K+) can suppress HER and accelerate CO2 reduction, but they still inevitably suffer from salt precipitation problems. In this study, we demonstrate that the sulfonate-based polyelectrolyte, polystyrene sulfonate (PSS), enables to reconstruct the electrode-electrolyte interface to significantly enhance the acidic CO2 electrolysis. Mechanistic studies reveal that PSS induces high local K+ concentrations through electrostatic interaction between PSS anions and K+. In situ spectroscopy reveals that PSS reshapes the interfacial hydrogen-bond (H-bond) network, which is attributed to the H-bonds between PSS anions and hydrated proton as well as the steric hindrance of the additive molecules. This greatly weakens proton transfer kinetics and leads to the suppression of undesirable HER. As a result, a Faradaic efficiency of 93.9% for CO can be achieved at 250 mA cm-2, simultaneous with a high single-pass carbon efficiency of 72.2% on commercial Ag catalysts in acid. This study highlights the important role of the electrode-electrolyte interface induced by polyelectrolyte additives in promoting electrocatalytic reactions.

16.
Adv Mater ; : e2410512, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39344867

RESUMO

Environmentally-benign materials play a pivotal role in advancing the scalability of energy storage devices. In particular, conjugated polymers constitute a potentially greener alternative to inorganic- and carbon-based materials. One challenge to wider implementation is the scarcity of n-doped conducting polymers to achieve full cells with high-rate performance. Herein, this work demonstrates the use of a self-doped n-doped conjugated polymer, namely poly(benzodifurandione) (PBDF), for fabricating aqueous supercapacitors. PBDF demonstrates a specific capacitance of 202 ± 3 F g-1, retaining 81% of the initial performance over 5000 cycles at 10 A g-1 in 2 m NaCl( aq ). PBDF demonstrates rate performances of up to 100 and 50 A g-1 at 1 and 2 mg cm-2, respectively. Electrochemical impedance analysis reveals a surface-mediated charge storage mechanism. Improvements can be achieved by adding reduced graphene oxide (rGO), thereby obtaining a specific capacitance of 288 ± 8 F g-1 and high-rate operation (270 A g-1). The performance of PBDF is examined in symmetric and asymmetric membrane-less cells, demonstrating high-rate performance, while retaining 83% of the initial capacitance after 100 000 cycles at 10 A g-1. PBDF thus offers new prospects for energy storage applications, showcasing both desirable performance and stability without the need for additives or binders and relying on environmentally friendly solutions.

17.
Biomed Mater ; 19(6)2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39312950

RESUMO

Anterior uveitis is one of the most prevalent forms of ocular inflammation caused by infections, trauma, and other idiopathic conditions if not treated properly, it can cause complete blindness. Therefore, this study aimed to formulate and evaluate dexamethasone sodium phosphate (DSP) loaded polyelectrolyte complex (PEC) nanoparticles (NPs) for the treatment of anterior uveitis. DSP-loaded PEC-NPs were formed through complex coacervation by mixing low molecular weight chitosan and the anionic polymer carboxy methyl cellulose (CMC). The formulations were optimized using Box-Behnken design and evaluated the effect of independent variables: Chitosan concentration, CMC concentration, and pH of chitosan solution on the dependent variables: particle size (PS), Polydispersity Index (PDI), pH of the formulation, and % entrapment efficacy (%EE). The PS, PDI, zeta potential, and pH of the optimized formulation were found 451 ± 82.0995 nm, 0.3807 ± 0.1862, +20.33 ± 1.04 mV and 6.8367 ± 0.0737 respectively. The %EE and drug loading of formulation were 61.66 ± 4.2914% and 21.442 ± 1.814% respectively.In vitrodrug release studies of optimized formulation showed the prolonged release up to 12 h whereas, the marketed formulation showed the burst release 85.625 ± 4.3062% in 1 h and 98.1462 ± 3.0921% at 6 h, respectively. Fourier transform infrared studies suggested the effective incorporation of the drug into the PEC-NPs formulation whereas differential scanning calorimetry and x-ray diffraction studies showed the amorphized nature of the drug in the formulation. Transmission electron microscopy study showed self-assembled, nearly spherical, core-shell nanostructures. The corneal permeation study showed higher permeation of the drug from PEC-NPs compared to the marketed formulation. Hen's Eggs test-Chorioallantoic Membrane test of the optimized formulation revealed non-irritant and safe for ocular administration. Therefore, DSP-loaded PEC-NPs are an effective substitute for conventional eye drops due to their ability to increase bioavailability through longer precorneal retention duration and sustained drug release.


Assuntos
Carboximetilcelulose Sódica , Quitosana , Dexametasona , Nanopartículas , Tamanho da Partícula , Polieletrólitos , Uveíte Anterior , Dexametasona/química , Dexametasona/administração & dosagem , Dexametasona/análogos & derivados , Quitosana/química , Carboximetilcelulose Sódica/química , Nanopartículas/química , Animais , Uveíte Anterior/tratamento farmacológico , Polieletrólitos/química , Coelhos , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Difração de Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia
18.
Anal Chim Acta ; 1321: 342997, 2024 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-39155106

RESUMO

BACKGROUND: Polyelectrolyte grafted 'soft' nanochannels are known to enhance electrokinetic energy conversion efficiency, paving the way for a sustainable energy harvesting mechanism. However, the true potential of their efficacy remains to be tapped, as attributed to a deficit in accounting for the interplay between solution pH and ion partitioning effect arising due to permittivity contrast between the coated layer and the bulk media, leading to predictions of an erroneous ionic distribution and a wrongly estimated electrokinetic response. RESULTS: We unravel the electrokinetic behavior of a pH-regulated zwitterionic polyelectrolyte layer grafted nanofluidic system. To this end, we derive a detailed theoretical formulation that considers the nuanced interplay between solution pH and the ion partitioning effect through a thermodynamically consistent ionic distribution. Here, for the first time, we demonstrate a non-monotonic trend in the streaming potential with an increase in the ion partitioning effect, in contrast to a monotonic increase as reported previously. Additionally, we identify a critical permittivity ratio specific to the solution pH at which maximum streaming potential can be obtained. SIGNIFICANCE: We shed light on the counterintuitive effect borne from the increased ion partitioning effect, unveiling a hitherto hidden facet of electrokinetics. By elucidating the delicate balance between solution pH, ion partitioning effect, and polyelectrolyte charge, our findings offer a comprehensive understanding of the multifaceted interplay shaping soft-electrokinetic systems, thereby paving the way for transformative advancements in energy conversion technologies.

19.
AAPS PharmSciTech ; 25(6): 182, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138709

RESUMO

Local anesthesia is essential in dental practices, particularly for managing pain in tooth socket wounds, yet improving drug delivery systems remains a significant challenge. This study explored the physicochemical characteristics of lidocaine hydrochloride (LH) incorporated into a polyelectrolyte complex and poloxamer thermosensitivity hydrogel, assessing its local anesthetic efficacy in mouse models and its onset and duration of action as topical anesthetics in clinical trials. The thermoresponsive hydrogel exhibited a rapid phase transition within 1-3 minutes and demonstrated pseudo-plastic flow behavior. Its release kinetics followed Korsmeyer-Peppas, with 50% of biodegradation occurring over 48 h. In mouse models, certain thermogels showed superior anesthetic effects, with rapid onset and prolonged action, as evidenced by heat tolerance in tail-flick and hot plate models. In clinical trials, the LH-loaded thermoresponsive hydrogel provided rapid numbness onset, with anesthesia (Ton) beginning at an average of 46.5 ± 22.5 seconds and lasting effectively (Teff) for 202.5 ± 41.0 seconds, ranging from 120 to 240 seconds, indicating sustained release. These results highlight the promising properties of these formulations: rapid onset, prolonged duration, mucoadhesion, biodegradability, and high anesthesia effectiveness. This study demonstrates the potential for advancing local anesthesia across various medical fields, emphasizing the synergy between material science and clinical applications to improve patient care and safety.


Assuntos
Anestésicos Locais , Sistemas de Liberação de Medicamentos , Hidrogéis , Lidocaína , Poloxâmero , Lidocaína/administração & dosagem , Lidocaína/química , Animais , Hidrogéis/química , Anestésicos Locais/administração & dosagem , Anestésicos Locais/química , Camundongos , Poloxâmero/química , Sistemas de Liberação de Medicamentos/métodos , Polieletrólitos/química , Masculino , Liberação Controlada de Fármacos , Humanos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/farmacocinética
20.
Int J Biol Macromol ; 277(Pt 3): 134316, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39094859

RESUMO

Due to dwindling petroleum resources and the need for environmental protection, the development of bio-based flame retardants has received much attention. In order to explore the feasibility of fully biomass polyelectrolyte complexes (PEC) for polyolefin flame retardant applications, chitosan (CS), sodium alginate (SA), and sodium phytate (SP) were used to prepare CS-based fully biomass PEC intercalated montmorillonite (MMT) hybrid biomaterials (SA-CS@MMT and SP-CS@MMT). The effects of two hybrid biomaterials on the fire safety and mechanical properties of intumescent flame-retardant polypropylene (PP) composites were compared. The SP-CS@MMT showed the best flame retardancy and toughening effect at the same addition amount. After adding 5 wt% SP-CS@MMT, the limiting oxygen index (LOI) value of PP5 reached 30.9 %, and the peak heat release rate (pHRR) decreased from 1348 kW/m2 to 163 kW/m2. In addition, the hydrogen bonding between polyelectrolyte complexes significantly improved the mechanical properties of PP composites. Compared with PP2, the tensile strength of PP5 increased by 59 %. This study provided an efficient and eco-friendly strategy for the large-scale production of renewable biomaterials with good thermal stability and expanded the application of macromolecular biomaterials in the field of fire safety.


Assuntos
Bentonita , Quitosana , Retardadores de Chama , Polieletrólitos , Polipropilenos , Quitosana/química , Bentonita/química , Polipropilenos/química , Polieletrólitos/química , Resistência à Tração , Química Verde/métodos , Materiais Biocompatíveis/química , Fenômenos Mecânicos
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