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1.
J Colloid Interface Sci ; 668: 678-690, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38710124

RESUMEN

Aerogels, as a unique porous material, are expected to be used as insulation materials to solve the global environmental and energy crisis. Using chitosan, citric acid, pectin and phytic acid as raw materials, an all-biomass-based aerogel with high modulus was prepared by the triple strategy of ionic, physical and chemical cross-linking through directional freezing technique. Based on this three-dimensional network, the aerogel exhibited excellent compressive modulus (24.89 ± 1.76 MPa) over a wide temperature range and thermal insulation properties. In the presence of chitosan, citric acid and phytic acid, the aerogel obtained excellent fire safety (LOI value up to 31.2%) and antibacterial properties (antibacterial activity against Staphylococcus aureus and Escherichia coli reached 81.98% and 67.43%). In addition, the modified aerogel exhibited excellent hydrophobicity (hydrophobic angle of 146°) and oil-water separation properties. More importantly, the aerogel exhibited a biodegradation rate of up to 40.31% for 35 days due to its all-biomass nature. This work provides a green and sustainable strategy for the production of highly environmentally friendly thermal insulation materials with high strength, flame retardant, antibacterial and hydrophobic properties.


Asunto(s)
Antibacterianos , Quitosano , Ácido Cítrico , Escherichia coli , Geles , Staphylococcus aureus , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/química , Geles/química , Quitosano/química , Ácido Cítrico/química , Biomasa , Interacciones Hidrofóbicas e Hidrofílicas , Porosidad , Ácido Fítico/química , Pectinas/química , Reactivos de Enlaces Cruzados/química , Pruebas de Sensibilidad Microbiana , Propiedades de Superficie , Tamaño de la Partícula , Temperatura
2.
Anal Chim Acta ; 1306: 342613, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38692794

RESUMEN

Glucose detection is of significant importance in providing information to the human health management. However, conventional enzymatic glucose sensors suffer from a limited long-term stability due to the losing activity of the enzymes. In this work, the AuNi bimetallic aerogel with a well-defined nanowire network is synthesized and applied as the sensing nanomaterial in the non-enzymatic glucose detection. The three-dimensional (3D) hierarchical porous structure of the AuNi bimetallic aerogel ensures the high sensitivity of the sensor (40.34 µA mM-1 cm-2). Theoretical investigation unveiled the mechanism of the boosting electrocatalytic activity of the AuNi bimetallic aerogel toward glucose. A better adhesion between the sensing nanomaterial and the screen-printing electrodes (SPEs) is obtained after the introduction of Ni. On the basis of a wide linearity in the range of 0.1-5 mM, an excellent selectivity, an outstanding long-term stability (90 days) as well as the help of the signal processing circuit and an M5stack development board, the as-prepared glucose sensor successfully realizes remote monitoring of the glucose concentration. We speculate that this work is favorable to motivating the technological innovations of the non-enzymatic glucose sensors and intelligent sensing devices.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Geles , Glucosa , Oro , Níquel , Técnicas Biosensibles/métodos , Níquel/química , Geles/química , Oro/química , Glucosa/análisis , Electrodos , Nanocables/química , Humanos , Límite de Detección
3.
Anal Chim Acta ; 1308: 342647, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38740456

RESUMEN

BACKGROUND: Presently, glyphosate (Gly) is the most extensively used herbicide globally, Nevertheless, its excessive usage has increased its accumulation in off-target locations, and aroused concerns for food and environmental safety. Commonly used detection methods, such as high-performance liquid chromatography and gas chromatography, have limitations due to expensive instruments, complex pre-processing steps, and inadequate sensitivity. Therefore, a facile, sensitive, and reliable Gly detection method should be developed. RESULTS: A photoelectrochemical (PEC) sensor consisting of a three-dimensional polymer phenylethnylcopper/nitrogen-doped graphene aerogel (PPhECu/3DNGA) electrode coupled with Fe3O4 NPs nanozyme was constructed for sensitive detection of Gly. The microscopic 3D network of electrodes offered fast transfer routes for photo-generated electrons and a large surface area for nanozyme loading, allowing high signal output and analytical sensitivity. Furthermore, the use of peroxidase-mimicking Fe3O4 NPs instead of natural enzyme improved the stability of the sensor against ambient temperature changes. Based on the inhibitory effect of Gly on the catalytic activity Fe3O4 NPs, the protocol achieved Gly detection in the range of 5 × 10-10 to 1 × 10-4 mol L-1. Additionally, feasibility of the detection was confirmed in real agricultural matrix including tea, maize seedlings, maize seeds and soil. SIGNIFICANCE: This work achieved facile, sensitive and reliable analysis towards Gly, and it was expected to inspire the design and utilization of 3D architectures in monitoring agricultural chemicals in food and environmental matrix.


Asunto(s)
Técnicas Electroquímicas , Electrodos , Glicina , Glifosato , Grafito , Nitrógeno , Procesos Fotoquímicos , Grafito/química , Glicina/análogos & derivados , Glicina/química , Glicina/análisis , Nitrógeno/química , Polímeros/química , Cobre/química , Geles/química , Herbicidas/análisis , Límite de Detección , Nanopartículas de Magnetita/química , Nanopartículas Magnéticas de Óxido de Hierro/química
4.
Sensors (Basel) ; 24(9)2024 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-38732893

RESUMEN

An abnormal level of dopamine (DA), a kind of neurotransmitter, correlates with a series of diseases, including Parkinson's disease, Willis-Ekbom disease, attention deficit hyperactivity disorder, and schizophrenia. Hence, it is imperative to achieve a precise, rapid detection method in clinical medicine. In this study, we synthesized nanocomposite carbon aerogels (CAs) doped with iron and iron carbide, based on algae residue-derived biomass materials, using Fe(NO3)3 as the iron source. The modified glassy carbon electrode (GCE) for DA detection, denoted as CAs-Fe/GCE, was prepared through surface modification with this composite material. X-ray photoelectron spectroscopy and X-ray diffraction characterization confirmed the successful doping of iron into the as-prepared CAs. Additionally, the electrochemical behavior of DA on the modified electrode surface was investigated and the results demonstrate that the addition of the CAs-Fe promoted the electron transfer rate, thereby enhancing their sensing performance. The fabricated electrochemical DA biosensor exhibits an accurate detection of DA in the concentration within the range of 0.01~200 µM, with a detection limit of 0.0033 µM. Furthermore, the proposed biosensor is validated in real samples, showing its high applicability for the detection of DA in beverages.


Asunto(s)
Técnicas Biosensibles , Carbono , Dopamina , Técnicas Electroquímicas , Electrodos , Hierro , Técnicas Biosensibles/métodos , Técnicas Biosensibles/instrumentación , Dopamina/análisis , Dopamina/química , Carbono/química , Hierro/química , Técnicas Electroquímicas/métodos , Geles/química , Límite de Detección , Espectroscopía de Fotoelectrones , Nanocompuestos/química
5.
Biomacromolecules ; 25(5): 3169-3177, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38684138

RESUMEN

Achieving precise control over gelator alignment and morphology is crucial for crafting tailored materials and supramolecular structures with distinct properties. We successfully aligned the self-assembled micelles formed by a functionalized dipeptide 2NapFF into long 1-D "gel noodles" by cross-linking with divalent metal chlorides. We identify the most effective cross-linker for alignment, enhancing mechanical stability, and imparting functional properties. Our study shows that Group 2 metal ions are particularly suited for creating mechanically robust yet flexible gel noodles because of their ionic and nondirectional bonding with carboxylate groups. In contrast, the covalent nature and high directional bonds of d-block metal ions with carboxylates tend to disrupt the self-assembly of 2NapFF. Furthermore, the 2NapFF-Cu noodles demonstrated selective antibacterial activity, indicating that the potent antibacterial property of the copper(II) ion is preserved within the cross-linked system. By merging insights into molecular alignment, gel extrusion processing, and integrating specific functionalities, we illustrate how the versatility of dipeptide-based gels can be utilized in creating next-generation soft materials.


Asunto(s)
Antibacterianos , Cobre , Geles , Antibacterianos/química , Antibacterianos/farmacología , Cobre/química , Cobre/farmacología , Geles/química , Reactivos de Enlaces Cruzados/química , Dipéptidos/química , Dipéptidos/farmacología , Micelas , Pruebas de Sensibilidad Microbiana , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos
6.
Int J Biol Macromol ; 267(Pt 1): 131447, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38588843

RESUMEN

The drug encapsulation efficiency, release rate and time, sustained release, and stimulus-response of carriers are very important for drug delivery. However, these always cannot obtained for the carrier with a single component. To improve the comprehensive performance of chitosan-based carriers for 5-Fu delivery, diatomite-incorporated hydroxypropyl cellulose/chitosan (DE/HPC/CS) composite aerogel microspheres were fabricated for the release of 5-fluorouracil (5-Fu), and the release performance was regulated with the content of diatomite, pH value, and external coating material. Firstly, the 5-Fu loaded DE/HPC/CS composite aerogel microspheres and Eudragit L100 coated microspheres were prepared with cross-linking followed by freeze-drying, and characterized by SEM, EDS, FTIR, XRD, DSC, TG, and swelling. The obtained aerogel microspheres have a diameter of about 0.5 mm, the weight percentage of F and Si elements on the surface are 0.55 % and 0.78 % respectively. The glass transition temperature increased from 179 °C to 181 °C and 185 °C with the incorporation of DE and coating of Eudragit, and the equilibrium swelling percentage of DE/HPC/CS (1.5:3:2) carriers are 101.52 %, 45.27 %, 67.32 % at pH 1.2, 5.0, 7.4, respectively. Then, the effect of DE content on the drug loading efficiency of DE/HPC/CS@5-Fu was investigated, with the increase of DE content, the highest encapsulation efficiency was 82.6 %. Finally, the release behavior of DE incorporated and Eudragit L100 Coated microspheres were investigated under different pH values, and evaluated with four kinetic models. The results revealed that the release rate of 5-Fu decreased with the increase of DE content, sustained release with extending time and pH-responsive were observed for the Eudragit-coated aerogel microspheres.


Asunto(s)
Celulosa , Celulosa/análogos & derivados , Quitosano , Preparaciones de Acción Retardada , Tierra de Diatomeas , Portadores de Fármacos , Liberación de Fármacos , Fluorouracilo , Microesferas , Ácidos Polimetacrílicos , Quitosano/química , Celulosa/química , Fluorouracilo/química , Fluorouracilo/administración & dosificación , Tierra de Diatomeas/química , Ácidos Polimetacrílicos/química , Portadores de Fármacos/química , Concentración de Iones de Hidrógeno , Geles/química
7.
Int J Biol Macromol ; 267(Pt 1): 131450, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38588838

RESUMEN

With the increasing severity of energy shortages and environmental pollution, there is an urgent need for advanced thermal insulation materials with excellent comprehensive performance, including low thermal conductivity, high flame resistance, and strong compressive strength. Herein, an anisotropic composite aerogel based on cellulose nanofibers (CNF), calcium alginate (CA), and boric acid (BA) is fabricated using a directional freeze-drying strategy. The CA and BA, as double cross-linking agents, associated with oriented porous structure provide the resultant aerogel with good mechanical strength. Additionally, self-flame retardant CA and BA act as synergistic flame retardants that endow the aerogel with excellent flame retardance properties such as a limiting oxygen index value of 44.2 %, UL-94 V-0 rating, and low heat release. Furthermore, this composite aerogel exhibits outstanding thermal insulation performance with a low thermal conductivity of approximately 30 mW m-1 K-1. Therefore, the composite aerogel is expected to have a wide potential application in areas such as construction, automotive industry, batteries, petrochemical pipelines, and high-temperature reaction devices.


Asunto(s)
Alginatos , Ácidos Bóricos , Celulosa , Retardadores de Llama , Geles , Nanofibras , Conductividad Térmica , Nanofibras/química , Ácidos Bóricos/química , Celulosa/química , Alginatos/química , Geles/química , Anisotropía , Porosidad
8.
Int J Biol Macromol ; 267(Pt 1): 131485, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38604429

RESUMEN

Global seafood consumption is estimated at 156 million tons annually, with an economic loss of >25 billion euros annually due to marine fish spoilage. In contrast to traditional smart packaging which can only roughly estimate food freshness, an intelligent platform integrating machine learning and smart aerogel can accurately predict remaining shelf life in food products, reducing economic losses and food waste. In this study, we prepared aerogels based on anthocyanin complexes that exhibited excellent environmental responsiveness, high porosity, high color-rendering properties, high biocompatibility, high stability, and irreversibility. The aerogel showed excellent indication properties for rainbow trout and proved suitable for fish storage environments. Among the four machine learning models, the radial basis function neural network and backpropagation network optimized by genetic algorithm demonstrated excellent monitoring performance. Also, the two-channel dataset provided more comprehensive information and superior descriptive capability. The three-layer structure of the monitoring platform provided a new paradigm for intelligent and sophisticated food packaging. The results of the study might be of great significance to the food industry and sustainable development.


Asunto(s)
Alginatos , Antocianinas , Colorimetría , Embalaje de Alimentos , Geles , Antocianinas/química , Embalaje de Alimentos/métodos , Alginatos/química , Geles/química , Colorimetría/métodos , Animales , Porosidad , Alimentos Marinos/análisis , Oncorhynchus mykiss , Aprendizaje Automático
9.
Int J Biol Macromol ; 267(Pt 1): 131584, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38615856

RESUMEN

Heterocyclic aromatic amines (HAAs) are the main carcinogens produced during thermal processing of protein-rich foods. In this paper, a composite aerogel (TOCNFCa) with a stabilized dual-network structure was prepared via a template for the in-situ synthesis of UiO-66 on cellulose for the adsorption of HAAs in food. The dual-network structure of TOCNFCa provides the composite aerogel with excellent wet strength, maintaining excellent compressive properties. With the in-situ grown UiO-66 content up to 71.89 wt%, the hierarchical porosity endowed TOCNFCa@UiO-66 with the ability to rapidly adsorb HAAs molecules with high capacity (1.44-5.82 µmol/g). Based on excellent thermal stability, adsorption capacity and anti-interference, TOCNFCa@UiO-66 achieved satisfactory recoveries of HAAs in the boiled marinade, which is faster and more economical than the conventional SPE method. Moreover, TOCNFCa@UiO-66 could maintain 84.55 % of the initial adsorption capacity after 5 times of reuse.


Asunto(s)
Aminas , Celulosa , Compuestos Heterocíclicos , Estructuras Metalorgánicas , Nanofibras , Ácidos Ftálicos , Celulosa/química , Adsorción , Aminas/química , Nanofibras/química , Estructuras Metalorgánicas/química , Compuestos Heterocíclicos/química , Geles/química , Porosidad
10.
Int J Biol Macromol ; 267(Pt 2): 131484, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38599421

RESUMEN

Adopting effective and efficient techniques for the treatment of heavy metal pollution in water bodies plays an important role in guaranteeing the quality of water and the sustainable development of water resources. In this study, GO, MMT and SA were used as raw materials to compare the adsorption behaviors of three alginate-based adsorbents crosslinked with different valence metal ions (Ca2+, Fe3+ and Zr4+) on Cu(II). The aerogels were based on sodium alginate as the matrix material with unique slit-shaped pore structures formed by stacking effect of sheets and chemical bonding. It was found that the pore structures of the aerogels were denser and more orderly with the increase of the valence states of the crosslinked ions, and the affinity for Cu(II) in planar configuration was stronger. The Zr4+-GMSA aerogel had the maximum adsorption capacity of 126.68 mg/g and the Kd of Cu(II) was up to 50.80 L/g, which exhibited good preferential adsorption performance. The adsorption mechanism of Mn+-GMSA aerogels on Cu(II) was mainly ionic exchange, surface complexation and physical adsorption, which was explored by combining XPS and EDS characterizations of Mn+-GMSA before and after adsorption. This scheme can provide valuable and meaningful contribution to realize the selective recovery of Cu(II).


Asunto(s)
Alginatos , Cobre , Contaminantes Químicos del Agua , Purificación del Agua , Cobre/química , Adsorción , Alginatos/química , Porosidad , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Iones/química , Cinética , Geles/química , Concentración de Iones de Hidrógeno
11.
Int J Biol Macromol ; 267(Pt 2): 131481, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38599431

RESUMEN

We developed an effective and eco-friendly strategy using chitosan gel-molten salt to achieve high loading (2.23 At. %) of single Fe-NX as assistive active sites. These sites were combined with small NiCo alloy NPs distributed on porous carbon aerogels to boost the ORR performance. The FeSAs-NiCo alloy@N-C sphere exhibits exceptional mass activity and specific activity of 3.705 A.mg-1 and 8.79 mA.cm-2(ECSA), respectively, at 0.85 V versus RHE. It has a superior onset potential of 1.08 V versus RHE, surpassing that of its nanoparticle Fe counterpart and NiCo alloy@N-C sphere. The significant improvement in ORR performance of the FeSAs-NiCo alloy@N-C sphere could be attributed to the positive effects of increased lattice strain due to the single atoms of Fe-NX hybridized with small NiCo alloy NPs. The chitosan gel-assisted molten salt strategy and assistive active sites of Fe-NX hybridized with NiCo alloy NPs regulate the electronic properties of the FeSAs-NiCo alloy@N-C sphere, both geometrically via lattice strain mismatch and electronically through shifting of the d-band center. This could influence the binding energies for oxygen and/or oxygen reduction intermediate adsorption/desorption. The additional improvement in the ORR performance of the FeSAs-NiCo alloy@N-C sphere also benefits from having a lower electrochemical activation energy.


Asunto(s)
Aleaciones , Quitosano , Geles , Oxidación-Reducción , Oxígeno , Quitosano/química , Oxígeno/química , Aleaciones/química , Geles/química , Hierro/química , Nanopartículas del Metal/química , Níquel/química , Cobalto/química , Catálisis , Sales (Química)/química
12.
Biomed Mater ; 19(4)2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38657627

RESUMEN

Tissue adhesives offer a plethora of advantages in achieving efficient wound closure over conventional sutures and staples. Such materials are of great value, especially in cases where suturing could potentially damage tissues or compromise blood flow or in cases of hard-to-reach areas. Besides providing wound closure, the tissue adhesives must also facilitate wound healing. Previously, plasma-based tissue adhesives and similar bioinspired strategies have been utilized to aid in wound healing. Still, their application is constrained by factors such as high cost, diminished biocompatibility, prolonged gelation times, inadequate swelling, quick resorption, as well as short-term and inconsistent efficacy. To address these limitations, we report the development of a highly biocompatible and ultrafast-gelling tissue adhesive hydrogels. Freeze-dried platelet-rich plasma, heat-denatured freeze-dried platelet-poor plasma, and gelatin were utilized as the base matrix. Gelation was initiated by adding tetrakis hydroxymethyl phosphonium chloride. The fabricated gels displayed rapid gelation (3-4 s), low swelling, increased proliferation, and migration against L929 cells and had porcine skin tissue adhesion strength similar to that of plasma-based commercial glue (Tisseel®).


Asunto(s)
Gelatina , Adhesivos Tisulares , Cicatrización de Heridas , Animales , Cicatrización de Heridas/efectos de los fármacos , Gelatina/química , Adhesivos Tisulares/química , Adhesivos Tisulares/farmacología , Ratones , Porcinos , Materiales Biocompatibles/química , Hidrogeles/química , Línea Celular , Ensayo de Materiales , Plasma Rico en Plaquetas , Proliferación Celular/efectos de los fármacos , Humanos , Piel/metabolismo , Geles/química , Movimiento Celular/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Plasma , Liofilización
13.
ACS Nano ; 18(19): 12096-12104, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38687972

RESUMEN

Direct harvesting of energy from moist air will be a promising route to supply electricity for booming wearable and distributed electronics, with the recent rapid development of the moisture-enabled electricity generator (MEG). However, the easy spatial distortion of rigid MEG materials under severe deformation extremely inconveniences the human body with intense physical activity, seriously hindering the desirable applications. Here, an intrinsically stretchable moisture-enabled electricity generator (s-MEG) is developed based on a well-fabricated stretchable functional ionic gel (SIG) with a flexible double-network structure and reversible cross-linking interactions, demonstrating stable electricity output performance even when stretched up to 150% strain and high human body conformality. This SIG exhibits ultrahigh tensile strain (∼600%), and a 1 cm × 1 cm SIG film-based s-MEG can generate a voltage of ∼0.4 V and a current of ∼5.7 µA when absorbing water from humidity air. Based on the strong adhesion and the excellent interface combination of SIG and rough fabric electrodes induced by the fabrication process, s-MEG is able to realize bending or twisting deformation and shows outstanding electricity output stability with ∼90% performance retention after 5000 cycles of bending tests. By connecting s-MEG units in series or parallel, an integrated device of "moisture-powered wristband" is developed to wear on the wrist of humans and drive a flexible sensor for tracking finger motions. Additionally, a comfortable "moisture-powered sheath" based on s-MEGs is created, which can be worn like clothing on human arms to generate energy while walking and flexing the elbow, which is promising in the field of wearable electronics.


Asunto(s)
Suministros de Energía Eléctrica , Geles , Dispositivos Electrónicos Vestibles , Humanos , Geles/química , Iones/química , Agua/química , Electrodos , Cuerpo Humano
14.
Biomacromolecules ; 25(5): 2659-2678, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38663862

RESUMEN

Peptide-polymer conjugates (PPCs) are of particular interest in the development of responsive, adaptive, and interactive materials due to the benefits offered by combining both building blocks and components. This review presents pioneering work as well as recent advances in the design of peptide-polymer conjugates, with a specific focus on their thermoresponsive behavior. This unique class of materials has shown great promise in the development of supramolecular structures with physicochemical properties that are modulated using soft and biorthogonal external stimuli. The temperature-induced self-assembly of PPCs into various supramolecular architectures, gelation processes, and tuning of accessible processing parameters to biologically relevant temperature windows are described. The discussion covers the chemical design of the conjugates, the supramolecular driving forces involved, and the mutual influence of the polymer and peptide segments. Additionally, some selected examples for potential biomedical applications of thermoresponsive PPCs in tissue engineering, delivery systems, tumor therapy, and biosensing are highlighted, as well as perspectives on future challenges.


Asunto(s)
Péptidos , Polímeros , Geles/química , Péptidos/química , Polímeros/química , Temperatura , Ingeniería de Tejidos/métodos
15.
J Colloid Interface Sci ; 666: 529-539, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38613975

RESUMEN

Elastic carbon aerogels have promising applications in the field of wearable sensors. Herein, a new strategy for preparing carbon aerogels with excellent compressive strength and strain, shape recovery, and fatigue resistance was proposed based on the structure design and carbonization optimization of nanocellulose-based precursor aerogels. By the combination of directional freezing and zinc ion cross-linking, bacterial cellulose (BC)/alginate (SA) composite aerogels with high elasticity and compressive strength were first achieved. The existance of zinc ions also significantly improved the carbon retention rate and inhibited structural shrinkage, thus making the carbon aerogels retain ultra-high elasticity and fatigue resistance after compression. Moreover, the carbon aerogel possessed excellent piezoresistive pressure sensing performance with a wide detection range of 0-7.8 kPa, high sensitivity of 11.04 kpa-1, low detection limit (2 % strain), fast response (112 ms), and good durability (over 1,000 cycles). Based on these excellent properties, the carbon aerogel pressure sensors were further successfully used for human motion monitoring, from joint motion to and speech recognition.


Asunto(s)
Alginatos , Carbono , Celulosa , Elasticidad , Geles , Dispositivos Electrónicos Vestibles , Carbono/química , Geles/química , Humanos , Celulosa/química , Alginatos/química , Anisotropía , Tamaño de la Partícula , Propiedades de Superficie , Zinc/química
16.
AAPS PharmSciTech ; 25(5): 90, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38649513

RESUMEN

To formulate and optimize Ozenoxacin nano-emulsion using Quality by Design (QbD) concept by means of Box-Behnken Design (BBD) and converting it to a gel to form Ozenoxacin nano-emulgel followed by physico-chemical, in-vitro, ex-vivo and in-vivo evaluation. This study demonstrates the application of QbD methodology for the development and optimization of an effective topical nanoemulgel formulation for the treatment of Impetigo focusing on the selection of appropriate excipients, optimization of formulation and process variables, and characterization of critical quality attributes. BBD was used to study the effect of "% of oil, % of Smix and homogenization speed" on critical quality attributes "globule size and % entrapment efficiency" for the optimisation of Ozenoxacin Nano-emulsion. Ozenoxacin loaded nano-emulgel was characterized for "description, identification, pH, specific gravity, amplitude sweep, viscosity, assay, organic impurities, antimicrobial effectiveness testing, in-vitro release testing, ex-vivo permeation testing, skin retention and in-vivo anti-bacterial activity". In-vitro release and ex-vivo permeation, skin retention and in-vivo anti-bacterial activity were found to be significantly (p < 0.01) higher for the nano-emulgel formulation compared to the innovator formulation (OZANEX™). Antimicrobial effectiveness testing was performed and found that even at 70% label claim of benzoic acid is effective to inhibit microbial growth in the drug product. The systematic application of QbD principles facilitated the successful development and optimization of a Ozenoxacin Nano-Emulsion. Optimised Ozenoxacin Nano-Emulgel can be considered as an effective alternative and found to be stable at least for 6 months at 40 °C / 75% RH and 30 °C / 75% RH.


Asunto(s)
Antibacterianos , Emulsiones , Impétigo , Quinolonas , Animales , Impétigo/tratamiento farmacológico , Ratones , Quinolonas/administración & dosificación , Quinolonas/química , Quinolonas/farmacología , Quinolonas/farmacocinética , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Antibacterianos/química , Emulsiones/química , Nanopartículas/química , Geles/química , Química Farmacéutica/métodos , Modelos Animales de Enfermedad , Aminopiridinas/administración & dosificación , Aminopiridinas/farmacología , Aminopiridinas/química , Aminopiridinas/farmacocinética , Excipientes/química , Piel/efectos de los fármacos , Piel/metabolismo , Pruebas de Sensibilidad Microbiana/métodos , Absorción Cutánea/efectos de los fármacos , Administración Tópica , Viscosidad , Composición de Medicamentos/métodos
17.
AAPS PharmSciTech ; 25(4): 77, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38589761

RESUMEN

Keratin has the potential to function as the gel matrix in an ophthalmic formulation for the encapsulation of the macrolide antibiotic azithromycin. The quality of this formulation was thoroughly evaluated through various analyses, such as in vitro release assessment, rheological examination, intraocular retention studies in rabbits, assessment of bacteriostatic efficacy, and safety evaluations. It is worth mentioning that the gel demonstrated shear thinning properties and exhibited characteristics of an elastic solid, thereby confirming its structural stability. The gel demonstrated a notable affinity for mucosal surfaces in comparison to traditional azithromycin aqueous solutions. In vitro release testing revealed that drug release transpired via diffusion mechanisms, following a first-order kinetic release pattern. Additionally, the formulated gel exhibited remarkable antibacterial efficacy against Staphylococcus aureus and Pseudomonas aeruginosa in bacteriostatic evaluations. Lastly, safety assessments confirmed that the gel eye drops induced minimal irritation and displayed no apparent cytotoxicity, indicating their good safety and biocompatibility for ocular application. Thus, these findings indicated that the prepared azithromycin gel eye drops complied with the requisite standards for ophthalmic preparations.


Asunto(s)
Conjuntivitis Bacteriana , Sistemas de Liberación de Medicamentos , Animales , Conejos , Azitromicina/farmacología , Queratinas/uso terapéutico , Conjuntivitis Bacteriana/tratamiento farmacológico , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Geles/química , Soluciones Oftálmicas/química
18.
Mol Pharm ; 21(5): 2394-2405, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38647653

RESUMEN

Doxorubicin (DOX) is one of the most commonly used anticancer drugs; however, its clinical application is greatly limited due to its toxicity and chemotherapy resistance. The delivery of DOX by liposomes (Lipos) can improve the blood circulation time in vivo and reduce toxic side effects, but the drug's accumulation in the tumor is often insufficient for effective treatment. In this study, we present a calcium cross-linked liposome gel for the encapsulation of DOX, demonstrating its superior long-term release capabilities compared to conventional Lipos. By leveraging this enhanced long-term release, we can enhance drug accumulation within tumors, ultimately leading to improved antitumor efficacy. Lipos were prepared using the thin-film dispersion method in this study. We utilized the ion-responsiveness of glutathione-gelatin (GSH-GG) to form the gel outside the Lipos and named the nanoparticles coated with GSH-GG on the outside of Lipos as Lipos@GSH-GG. The average size of Lipos@GSH-GG was around 342.9 nm, with a negative charge of -25.6 mV. The in vitro experiments revealed that Lipos@GSH-GG exhibited excellent biocompatibility and slower drug release compared to conventional Lipos. Further analysis of cellular uptake and cytotoxicity demonstrated that Lipos@GSH-GG loading DOX (DOX&Lipos@GSH-GG) exhibited superior long-term release effects and lower toxic side effects compared to Lipos loading DOX (DOX&Lipos). Additionally, the findings regarding the long-term release effect in vivo and the tumor accumulation within tumor-bearing mice of Lipos@GSH-GG suggested that, compared to Lipos, it demonstrated superior long-term release capabilities and achieved greater drug accumulation within tumors. In vivo antitumor efficacy experiments showed that DOX&Lipos@GSH-GG demonstrated superior antitumor efficacy to DOX&Lipos. Our study highlights Lipos@GSH-GG as a promising nanocarrier with the potential to enhance efficacy and safety by means of long-term release effects and may offer an alternative approach for effective antitumor therapy in the future.


Asunto(s)
Calcio , Doxorrubicina , Liberación de Fármacos , Glutatión , Liposomas , Doxorrubicina/farmacología , Doxorrubicina/química , Doxorrubicina/administración & dosificación , Doxorrubicina/farmacocinética , Animales , Ratones , Liposomas/química , Humanos , Calcio/química , Calcio/metabolismo , Glutatión/química , Femenino , Geles/química , Gelatina/química , Ratones Desnudos , Nanopartículas/química , Ratones Endogámicos BALB C , Línea Celular Tumoral , Ensayos Antitumor por Modelo de Xenoinjerto , Antibióticos Antineoplásicos/administración & dosificación , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacocinética , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Antineoplásicos/farmacología , Antineoplásicos/química , Antineoplásicos/administración & dosificación , Reactivos de Enlaces Cruzados/química , Sistemas de Liberación de Medicamentos/métodos
19.
Talanta ; 274: 126016, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38599118

RESUMEN

The present study investigates the use of dextrins (maltodextrin, ß-cyclodextrin, and hydroxypropyl-ß-cyclodextrin) to improve the efficiency of the agarose-based gel electromembrane extraction technique for extracting chiral basic drugs (citalopram, hydroxyzine, and cetirizine). Additionally, it examines the enantioselectivity of the extraction process for these drugs. To achieve these, dextrins were incorporated into either the sample solution, the membrane, or the acceptor solution, and then the extraction procedure was performed. Enantiomers were separated and analyzed using a capillary electrophoresis device equipped with a UV detector. The results obtained under the optimal extraction conditions (sample solution pH: 4.0, acceptor solution pH: 2.0, gel membrane pH: 3.0, agarose concentration: 3 % w/v, stirring rate: 1000 rpm, gel thickness: 4.4 mm, extraction voltage: 62.3 V, and extraction time: 32.1 min) indicated that incorporating dextrins into either the sample solution, membrane or the acceptor solution enhances extraction efficiency by 17.3-23.1 %. The most significant increase was observed when hydroxypropyl-ß-cyclodextrin was added to the acceptor solution. The findings indicated that the inclusion of hydroxypropyl-ß-cyclodextrin in the sample solution resulted in an enantioselective extraction, yielding an enantiomeric excess of 6.42-7.14 %. The proposed method showed a linear range of 5.0-2000 ng/mL for enantiomers of model drugs. The limit of detection and limit of quantification for all enantiomers were found to be < 4.5 ng/mL and <15.0 ng/mL, respectively. Intra- and inter-day RSDs (n = 4) were less than 10.8 %, and the relative errors were less than 3.2 % for all the enantiomers. Finally, the developed method was successfully applied to determine concentrations of enantiomers in a urine sample with relative recoveries of 96.8-99.2 %, indicating good reliability of the developed method.


Asunto(s)
Dextrinas , Geles , Membranas Artificiales , Estereoisomerismo , Dextrinas/química , Geles/química , Electroforesis Capilar/métodos , Hidroxizina/análisis , Hidroxizina/aislamiento & purificación , Hidroxizina/química , Hidroxizina/orina , beta-Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina/química , Cetirizina/química , Cetirizina/orina , Cetirizina/análisis , Cetirizina/aislamiento & purificación , Concentración de Iones de Hidrógeno , Preparaciones Farmacéuticas/análisis , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/aislamiento & purificación , Preparaciones Farmacéuticas/orina , Sefarosa/química
20.
J Environ Manage ; 358: 120909, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38642487

RESUMEN

Achieving an equilibrium between exceptional oil absorption and remarkable elasticity has emerged as a formidable challenge for magnetic porous materials designed for oil absorption. Here, we propose an original, magnetic and superhydrophobic cellulose nanofibril (CNF) based aerogel system with a rope-ladder like skeleton by to greatly improve the issue. Within this system, CNF as the skeleton was combined with multiwalled carbon nanotubes (MWCNT)@Fe3O4 as the magnetic and enhanced component, both methyltrimethoxysilane (MTMS) and acetonitrile-extracted lignin (AEL) as the soft-hard associating constituents. The resultant CNF based aerogel shows a rope-ladder like pore structure to contribute to high elasticity and excellent oil absorption (28.34-61.09 g/g for various oils and organic solvents) under the synergistic effect of Fe3O4@MWCNT, AEL and MTMS, as well as good specific surface area (27.97 m2/g), low density (26.4 mg/cm3). Notably, despite the introduced considerable proportion (0.5 times of mass-CNF) of Fe3O4@MWCNT, the aerogel retained an impressive compression-decompression rate (88%) and the oil absorption efficiency of above 87% for various oils due to the soft-hard associating structure supported by both MTMS and AEL. This study provides a prospective strategy to balance between high elasticity and excellent oil absorption of CNF based aerogel doping inorganic particles.


Asunto(s)
Celulosa , Interacciones Hidrofóbicas e Hidrofílicas , Nanofibras , Celulosa/química , Nanofibras/química , Aceites/química , Geles/química , Nanotubos de Carbono/química , Elasticidad , Porosidad
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