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1.
Molecules ; 26(5)2021 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-33652827

RESUMEN

The application of physiologically based pharmacokinetic models to nanoparticles is still very restricted and challenging, owing to the complicated in vivo transport mechanisms involving nanoparticles, including phagocytosis, enhanced permeability and retention effects, cellular recognition, and internalisation, enzymatic degradation, lymphatic transport, and changes in physical properties. In our study, five nanoparticle formulations were synthesised using polycaprolactone as a framework material and methoxy poly (ethylene glycol)-poly(ε-caprolactone) as a long-circulating decorating material, as well as types of environmentally responsive near-infrared aza-boron-dipyrromethene dyes. According to quantification data and direct visualisation involving specific organs, a phagocytosis physiologically based pharmacokinetic model was developed to describe the dynamics of nanoparticles within and between organs in mice, considering cellular mechanisms involving phagocytosis and enhanced permeability and retention effects. Our results offer a better understanding of the in vivo fate of polymeric nanoparticles.


Asunto(s)
Colorantes/química , Sistemas de Liberación de Medicamentos , Nanopartículas/química , Farmacocinética , Animales , Simulación por Computador , Humanos , Ratones , Poliésteres/química , Polietilenglicoles/química , Polímeros/química
2.
Molecules ; 26(4)2021 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-33672710

RESUMEN

The presence of excited-states and charge-separated species was identified through UV and visible laser pump and visible/near-infrared probe femtosecond transient absorption spectroscopy in spin coated films of poly[N-9″-heptadecanyl-2,7-carbazole-alt-5,5-(4,7-di-2-thienyl-2',1',3'-benzothiadiazole)] (PCDTBT) nanoparticles and mesoparticles. Optical gain in the mesoparticle films is observed after excitation at both 400 and 610 nm. In the mesoparticle film, charge generation after UV excitation appears after around 50 ps, but little is observed after visible pump excitation. In the nanoparticle film, as for a uniform film of the pure polymer, charge formation was efficiently induced by UV excitation pump, while excitation of the low energetic absorption states (at 610 nm) induces in the nanoparticle film a large optical gain region reducing the charge formation efficiency. It is proposed that the different intermolecular interactions and molecular order within the nanoparticles and mesoparticles are responsible for their markedly different photophysical behavior. These results therefore demonstrate the possibility of a hitherto unexplored route to stimulated emission in a conjugated polymer that has relatively undemanding film preparation requirements.


Asunto(s)
Carbazoles/química , Nanopartículas/química , Polímeros/química , Compuestos de Azufre/química , Semiconductores
3.
Molecules ; 26(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33668746

RESUMEN

Cancer immunotherapies have generated some miracles in the clinic by orchestrating our immune system to combat cancer cells. However, the safety and efficacy concerns of the systemic delivery of these immunostimulatory agents has limited their application. Nanomedicine-based delivery strategies (e.g., liposomes, polymeric nanoparticles, silico, etc.) play an essential role in improving cancer immunotherapies, either by enhancing the anti-tumor immune response, or reducing their systemic adverse effects. The versatility of working with biocompatible polymers helps these polymeric nanoparticles stand out as a key carrier to improve bioavailability and achieve specific delivery at the site of action. This review provides a summary of the latest advancements in the use of polymeric micelles for cancer immunotherapy, including their application in delivering immunological checkpoint inhibitors, immunostimulatory molecules, engineered T cells, and cancer vaccines.


Asunto(s)
Inmunoterapia , Neoplasias/terapia , Polímeros/química , Animales , Sistemas de Liberación de Medicamentos , Humanos , Micelas , Nanomedicina , Nanopartículas/química , Neoplasias/inmunología
4.
Molecules ; 26(5)2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33669016

RESUMEN

The search for new biomedical applications of dendrimers has promoted the synthesis of new radical-based molecules. Specifically, obtaining radical dendrimers has opened the door to their use in various fields such as magnetic resonance imaging, as anti-tumor or antioxidant agents, or the possibility of developing new types of devices based on the paramagnetic properties of organic radicals. Herein, we present a mini review of radical dendrimers based on polyphosphorhydrazone, a new type of macromolecule with which, thanks to their versatility, new metal-free contrast agents are being obtained, among other possible applications.


Asunto(s)
Dendrímeros/química , Hidrazonas/química , Organofosfonatos/química , Polímeros/química , Dendrímeros/síntesis química , Radicales Libres/síntesis química , Radicales Libres/química , Humanos , Hidrazonas/síntesis química , Estructura Molecular , Organofosfonatos/síntesis química , Polímeros/síntesis química
5.
Molecules ; 26(4)2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33669746

RESUMEN

The new coordination polymers (CPs) [Zn(µ-1κO1:1κO2-L)(H2O)2]n·n(H2O) (1) and [Cd(µ4-1κO1O2:2κN:3,4κO3-L)(H2O)]n·n(H2O) (2) are reported, being prepared by the solvothermal reactions of 5-{(pyren-4-ylmethyl)amino}isophthalic acid (H2L) with Zn(NO3)2.6H2O or Cd(NO3)2.4H2O, respectively. They were synthesized in a basic ethanolic medium or a DMF:H2O mixture, respectively. These compounds were characterized by single-crystal X-ray diffraction, FTIR spectroscopy, thermogravimetric and elemental analysis. The single-crystal X-ray diffraction analysis revealed that compound 1 is a one dimensional linear coordination polymer, whereas 2 presents a two dimensional network. In both compounds, the coordinating ligand (L2-) is twisted due to the rotation of the pyrene ring around the CH2-NH bond. In compound 1, the Zn(II) metal ion has a tetrahedral geometry, whereas, in 2, the dinuclear [Cd2(COO)2] moiety acts as a secondary building unit and the Cd(II) ion possesses a distorted octahedral geometry. Recently, several CPs have been explored for the cyanosilylation reaction under conventional conditions, but microwave-assisted cyanosilylation of aldehydes catalyzed by CPs has not yet been well studied. Thus, we have tested the solvent-free microwave-assisted cyanosilylation reactions of different aldehydes, with trimethylsilyl cyanide, using our synthesized compounds, which behave as highly active heterogeneous catalysts. The coordination polymer 1 is more effective than 2, conceivably due to the higher Lewis acidity of the Zn(II) than the Cd(II) center and to a higher accessibility of the metal centers in the former framework. We have also checked the heterogeneity and recyclability of these coordination polymers, showing that they remain active at least after four recyclings.


Asunto(s)
Aldehídos/química , Cianuros/química , Microondas , Polímeros/química , Pirenos/química , Compuestos de Trimetilsililo/química , Catálisis , Enlace de Hidrógeno , Ligandos , Modelos Moleculares , Conformación Molecular , Polímeros/síntesis química , Solventes , Termogravimetría
6.
Molecules ; 26(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670156

RESUMEN

Recently, metal-coordinated orthogonal self-assembly has been used as a feasible and efficient method in the construction of polymeric materials, which can also provide supramolecular self-assembly complexes with different topologies. Herein, a cryptand with a rigid pyridyl group on the third arm derived from BMP32C10 was synthesized. Through coordination-driven self-assembly with a bidentate organoplatinum(II) acceptor or tetradentate Pd(BF4)2•4CH3CN, a di-cryptand complex and tetra-cryptand complex were prepared, respectively. Subsequently, through the addition of a di-paraquat guest, linear and cross-linked supramolecular polymers were constructed through orthogonal self-assembly, respectively. By comparing their proton nuclear magnetic resonance (1H NMR) and diffusion-ordered spectroscopy (DOSY) spectra, it was found that the degrees of polymerization were dependent not only on the concentrations of the monomers but also on the topologies of the supramolecular polymers.


Asunto(s)
Complejos de Coordinación/química , Éteres Cíclicos/química , Metales/química , Paraquat/química , Bases de Schiff/química , Sustancias Macromoleculares/química , Estructura Molecular , Polímeros/química
7.
Molecules ; 26(4)2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33671921

RESUMEN

Coinage metal(I)···metal(I) interactions are widely of interest in fields such as supramolecular assembly and unique luminescent properties, etc. Only two types of polynuclear silver(I) pyrazolato complexes have been reported, however, and no detailed spectroscopic characterizations have been reported. An unexpected synthetic method yielded a polynuclear silver(I) complex [Ag(µ-L1Clpz)]n (L1Clpz- = 4-chloride-3,5-diisopropyl-1-pyrazolate anion) by the reaction of {[Ag(µ-L1Clpz)]3}2 with (nBu4N)[Ag(CN)2]. The obtained structure was compared with the known hexanuclear silver(I) complex {[Ag(µ-L1Clpz)]3}2. The Ag···Ag distances in [Ag(µ-L1Clpz)]n are slightly shorter than twice Bondi's van der Waals radius, indicating some Ag···Ag argentophilic interactions. Two Ag-N distances in [Ag(µ-L1Clpz)]n were found: 2.0760(13) and 2.0716(13) Å, and their N-Ag-N bond angles of 180.00(7)° and 179.83(5)° indicate that each silver(I) ion is coordinated by two pyrazolyl nitrogen atoms with an almost linear coordination. Every five pyrazoles point in the same direction to form a 1-D zig-zag structure. Some spectroscopic properties of [Ag(µ-L1Clpz)]n in the solid-state are different from those of {[Ag(µ-L1Clpz)]3}2 (especially in the absorption and emission spectra), presumably attributable to this zig-zag structure having longer but differently arranged intramolecular Ag···Ag interactions of 3.39171(17) Å. This result clearly demonstrates the different physicochemical properties in the solid-state between 1-D coordination polymer and metalacyclic trinuclear (hexanuclear) or tetranuclear silver(I) pyrazolate complexes.


Asunto(s)
Polímeros/síntesis química , Pirazoles/síntesis química , Plata/química , Cristalografía por Rayos X , Luminiscencia , Conformación Molecular , Polímeros/química , Pirazoles/química , Espectrofotometría Ultravioleta , Temperatura
8.
Int J Nanomedicine ; 16: 2247-2269, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33776431

RESUMEN

Acute lung injury (ALI) or its aggravated stage acute respiratory distress syndrome (ARDS) may lead to a life-threatening form of respiratory failure, resulting in high mortality of up to 30-40% in most studies. Although there have been decades of research since ALI was first described in 1967, the clinical therapeutic alternatives for ALI are still in a state of limited availability. Supportive treatment and mechanical ventilation still have priority. Despite some preclinical studies demonstrating the benefit of pharmacological interventions, none of these has been proved completely effective to date. Recent advances in nanotechnology may shed new light on the pharmacotherapy of ALI. Nanomedicine possesses targeting and synergistic therapeutic capability, thus boosting pharmaceutical efficacy and mitigating the side effects. Currently, a variety of nanomedicine with diverse frameworks and functional groups have been elaborately developed, in accordance with their lung targeting ability and the pathophysiology of ALI. The in-depth review of the current literature reveals that liposomes, polymers, inorganic materials, cell membranes, platelets, and other nanomedicine approaches have conferred attractive therapeutic benefits for ALI treatment. In this review, we explore the recent progress in the study of the nanomedicine-based therapy of ALI, presenting various nanomedical approaches, drug choices, therapeutic strategies, and outcomes, thereby providing insight into the trends.


Asunto(s)
Lesión Pulmonar Aguda/terapia , Nanomedicina , Animales , Humanos , Lípidos/química , Polímeros/química , /terapia
9.
AAPS PharmSciTech ; 22(3): 99, 2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33709248

RESUMEN

The objective of this work was to investigate the influence of tablet location along the bottom of a USP apparatus II vessel on polymer erosion and drug release of surface-erodible sustained-release tablets using computational simulation methods. Computational fluid dynamics (CFD) methods were performed to simulate the velocity distribution. A mathematical model was developed to describe polymer erosion and tablet deformation according to the mass transfer coefficient. Numerical analysis was used to simulate drug release controlled by drug diffusion and polymer erosion. The results indicated that tablets located at the off-center position deformed faster than the tablets located at the center position. However, tablet location had no profound impact on drug release rate since all drug release profiles were "similar" according to the f2 similarity values which were above 50. Hence, our simulation supported that the USP apparatus II was a reliable and robust device for the dissolution testing of surface-erodible sustained-release tablets.


Asunto(s)
Simulación por Computador , Liberación de Fármacos , Polímeros/química , Polímeros/farmacocinética , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Hidrodinámica , Solubilidad , Comprimidos
10.
Int J Nanomedicine ; 16: 1361-1376, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33658777

RESUMEN

Object: High targeting and efficient cytotoxicity toward tumor cells endow NPs excellent anti-tumor activity. Herein, a peptide polymer possessing dual-targeting ability and double therapeutic activity was developed and named TGMF, which can form NPs through self-assembly. It is composed of four functional modules: 1) Active targeting peptide TMTP1 (T) deliver NPs to tumors specifically; 2) Therapeutic peptide GO-203 (G), which can significantly inhibit tumor growth by disrupting the redox balance in cells; 3) A passively targeted enzyme-responsive peptide PLGLGA (M), which can be cleaved specifically by metalloproteinase-2 (MMP-2) highly expressed in the tumor microenvironment (TME); and 4) Hexadecyl (F), which has strong hydrophobicity, can promote the self-assembly of TGMF NPs. Methods: Five modular peptide probes, namely, TGF, TMF, TGM, GMF, and TGMF were synthesized and self-assembled into NPs in solution. The characterization, enzyme reactivity, and cytotoxicity of NPs were evaluated in vitro, and the pharmacokinetics, bio-distribution, anti-tumor activity of NPs were investigated in vivo. In addition, transcriptome sequencing identified the intracellular signaling pathway-related genes involved in the anti-tumor effect of TGMF. Results: Upon enzyme cleavage, two types of nanostructure, NPs and nanofibers (NFs), were detected under TEM. Moreover, the cytotoxicity and anti-invasion activity of TGMF against tumor cells used were strongest among the five modular probes examined in vitro. TGMF increased reactive oxygen species (ROS) levels in cytoplasm and produced numerous NFs in extracellular interval and intracellular space. Transcriptome sequencing revealed that TGMF caused 446 genes' down-regulation and 270 genes' up-regulation in HeLa cells. In vivo, TGMF has a good anti-tumor effect, effectively prolonging the survival time of HeLa-tumor-bearing mice without systemic side effects. Conclusion: Integration of multiple functional modules into NPs could be a promising strategy for the future of nanomedicine design towards tumor treatment.


Asunto(s)
Antineoplásicos/uso terapéutico , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Femenino , Células HeLa , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones Endogámicos BALB C , Ratones Desnudos , Nanofibras/química , Nanofibras/ultraestructura , Nanopartículas/ultraestructura , Invasividad Neoplásica , Metástasis de la Neoplasia , Neoplasias/genética , Péptidos/química , Polímeros/química , Análisis de Componente Principal , Especies Reactivas de Oxígeno/metabolismo , Transcriptoma/efectos de los fármacos , Transcriptoma/genética , Microambiente Tumoral/efectos de los fármacos
11.
Int J Nanomedicine ; 16: 1587-1600, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33664573

RESUMEN

Background: Halofuginone hydrobromide (HF) is a synthetic analogue of the naturally occurring quinazolinone alkaloid febrifugine, which has potential therapeutic effects against breast cancer, however, its poor water solubility greatly limits its pharmaceutical application. D-α-tocopherol polyethylene glycol 1000 succinate (TPGS) is a water-soluble derivative of vitamin E, which can self-assemble to form polymeric micelles (PMs) for encapsulating insoluble anti-tumor drugs, thereby effectively enhancing their anti-cancer effects. Methods: HF-loaded TPGS PMs (HTPMs) were manufactured using a thin-film hydration technique, followed by a series of characterizations, including the hydrodynamic diameter (HD), zeta potential (ZP), stability, drug loading (DL), encapsulation efficiency (EE), and in vitro drug release. The anti-cancer effects and potential mechanism of HTPMs were investigated in the breast cell lines MDA-MB-231 and MCF-7, and normal breast epithelial cell line Eph-ev. The breast cancer-bearing BALB/c nude mouse model was successfully established by subcutaneous injection of MDA-MB-231 cells and used to evaluate the in vivo therapeutic effect and safety of the HTPMs. Results: The optimized HTPMs had an HD of 17.8±0.5 nm and ZP of 14.40±0.1 mV. These PMs exhibited DL of 12.94 ± 0.46% and EE of 90.6 ± 0.85%, along with excellent storage stability, dilution tolerance and sustained drug release in pH-dependent manner within 24 h compared to free HF. Additionally, the HTPMs had stronger inhibitory effects than free HF and paclitaxel against MDA-MB-231 triple-negative breast cancer cells, and little toxicity in normal breast epithelial Eph-ev cells. The HTPMs induced cell cycle arrest and apoptosis of MDA-MB-231 by disrupting the mitochondrial membrane potential and enhancing reactive oxygen species formation. Evaluation of in vivo anti-tumor efficacy demonstrated that HTPMs exerted a stronger tumor inhibition rate (68.17%) than free HF, and exhibited excellent biocompatibility. Conclusion: The findings from this study indicate that HTPMs holds great clinical potential for treating triple-negative breast cancer.


Asunto(s)
Composición de Medicamentos , Micelas , Piperidinas/uso terapéutico , Polímeros/química , Quinazolinonas/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Vitamina E/química , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Endogámicos BALB C , Ratones Desnudos , Paclitaxel/uso terapéutico , Piperidinas/farmacología , Quinazolinonas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Resultado del Tratamiento , Neoplasias de la Mama Triple Negativas/ultraestructura
12.
Nat Commun ; 12(1): 1367, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33649338

RESUMEN

Effective control of pain management has the potential to significantly decrease the need for prescription opioids following a surgical procedure. While extended release products for pain management are available commercially, the implementation of a device that safely and reliably provides extended analgesia and is sufficiently flexible to facilitate a diverse array of release profiles would serve to advance patient comfort, quality of care and compliance following surgical procedures. Herein, we review current polymeric systems that could be utilized in new, controlled post-operative pain management devices and highlight where opportunities for improvement exist.


Asunto(s)
Sistemas de Liberación de Medicamentos , Manejo del Dolor , Dolor Postoperatorio/tratamiento farmacológico , Polímeros/química , Analgésicos/administración & dosificación , Analgésicos/uso terapéutico , Animales , Humanos , Control Social Formal
13.
Carbohydr Polym ; 260: 117792, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712140

RESUMEN

Methylcellulose (MC) has received considerable attention because of its thermogelation behavior in aqueous solutions upon heating; however, the accompanied macro-phase separation results in demixing and detriment of thickening power. To alleviate this drawback, a novel family of hydrophilically modified methylcelluloses (HMMCs) was prepared by introducing acylamino, carboxyl, and amino groups onto MC side chains. Above association temperature (Tass), MC solutions experienced obvious macro-phase separation and thermothinning phenomenon; on the contrary, HMMCs solutions exhibited thermo- and salt-thickening behaviors, and Tass could be adjusted from 44 °C to 87 °C by altering the nature of HMMCs or salt content in solutions. The mechanism to eliminate the macro-phase separation of HMMC stems from the balance between hydrophilicity and hydrophobicity. This work opens a new avenue for cellulose derivatives to sustain their thermoviscosifying ability and widen their applications in hostile environments.


Asunto(s)
Metilcelulosa/química , Polímeros/química , Interacciones Hidrofóbicas e Hidrofílicas , Reología , Temperatura , Viscosidad
14.
Carbohydr Polym ; 260: 117799, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712147

RESUMEN

Bacillus amyloliquefaciens strain PPL shows a potential for the control of phytopathogenic fungi. In the present study, upon growing the strain PPL on various forms of chitosan (0.5 % powder, 0.1 % soluble, and 0.15 % colloidal) as the carbon source, the antifungal activity on tomato Fusarium wilt correlated with the activity of chitosanase and ß-1,3-glucanase. The colloidal substrate-based strain PPL fermentation displayed the highest degree of spore germination inhibition (79.5 %) and biocontrol efficiency (76.0 %) in tomato by increased biofilm formation. The colloidal culture upregulated the expression of chitosanase gene (5.9-fold), and the powder attributed to the expression of cyclic lipopeptides-genes (2.5-5.7 fold). Moreover, the three chitosan cultures induced the morphological changes of Fusarium oxysporum. These results suggest that the choice of growth substrate synergistically affects the production of secondary metabolites by PPL strain, and consequently its antifungal activity.


Asunto(s)
Quitosano/química , Polímeros/química , Antifúngicos/metabolismo , Antifúngicos/farmacología , Bacillus amyloliquefaciens/enzimología , Bacillus amyloliquefaciens/crecimiento & desarrollo , Bacillus amyloliquefaciens/fisiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Técnicas de Cultivo Celular por Lotes , Biopelículas , Fusarium/efectos de los fármacos , Glicósido Hidrolasas/genética , Glicósido Hidrolasas/metabolismo , Lipopéptidos/metabolismo , Lycopersicon esculentum/microbiología
15.
Carbohydr Polym ; 260: 117827, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712167

RESUMEN

Alginates, a kind of naturally occurring polysaccharides, have been exploited for functional materials owing to their versatility, sustainability, nontoxicity, and relatively low cost. Inherent flame retardancy is one of the most attractive features of alginates, as it enables the high-value-added utilization of alginates for eco-friendly flame-retardant materials. Now, the influence of metal ions on the flame retardancy and pyrolysis behaviors of alginates has been systematically studied; besides, the applications of alginates for flame-retardant materials have been greatly developed, such as for preparing flame-retardant fibers, fabrics, aerogel composites, and foams, as well as serving as a component or modifier of functional coatings, hybrids, and additives. This review will give an overview of the recent progress and the prospects of using alginates in flame-retardant fields, which can guide the design of bio-based flame retardants and benefit the further development of more diverse applications of alginates.


Asunto(s)
Alginatos/química , Retardadores de Llama/análisis , Geles/química , Metales/química , Polímeros/química , Pirólisis , Viscosidad
16.
Carbohydr Polym ; 260: 117830, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712169

RESUMEN

The manifold array of saccharide linkages leads to a great variety of polysaccharide architectures, comprising three conformations in aqueous solution: compact sphere, random coil, and rigid rod. This conformational variation limits the suitability of the commonly applied molecular weight cut-off (MWCO) as selection criteria for polysaccharide ultrafiltration membranes, as it is based on globular marker proteins with narrow Mw and hydrodynamic volume relation. Here we show the effect of conformation on ultrafiltration performance using randomly coiled pullulan and rigid rod-like scleroglucan as model polysaccharides for membrane rejection and molecular weight distribution. Ultrafiltration with a 10 kDa polyethersulfone membrane yielded significant different recoveries for pullulan and scleroglucan showing 1% and 71%, respectively. We found deviations greater than 77-fold between nominal MWCO and apparent Mw of pullulan and scleroglucan, while recovering over 90% polysaccharide with unchanged Mw. We anticipate our work as starting point towards an optimized membrane selection for polysaccharide applications.


Asunto(s)
Polisacáridos/química , Ultrafiltración/métodos , Glucanos/química , Glucanos/aislamiento & purificación , Membranas Artificiales , Conformación Molecular , Peso Molecular , Polímeros/química , Polisacáridos/aislamiento & purificación , Sulfonas/química
17.
Carbohydr Polym ; 260: 117836, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712173

RESUMEN

pH-sensitive polymeric dyes were fabricated by grafting phenol red (PR) and rosolic acid (RA) onto chitosan (CS) by a facile method. Successful grafting was confirmed by 1H NMR, FT-IR, UV-vis, XRD, and elemental analysis. The polymeric dyes exhibited no cell toxicity. The colorimetric pH-sensing films were fabricated by blending the polymeric dyes with CS to establish their pH-dependent color properties. The film color changed in the pH range 4-10, which may indicate food spoilage or wound status. Covalently grafting of polymeric dyes in the films led to excellent color stability, leaching resistance, and reversibility. Hence, the synthesized polymeric dyes had potential as pH-indicative colorants for food and biomedical fields.


Asunto(s)
Quitosano/química , Colorantes/síntesis química , Polímeros/química , Infecciones Bacterianas/diagnóstico , Línea Celular , Supervivencia Celular/efectos de los fármacos , Colorantes/química , Colorantes/farmacología , Almacenamiento de Alimentos , Humanos , Concentración de Iones de Hidrógeno , Fenolsulfonftaleína/química
18.
Molecules ; 26(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670378

RESUMEN

Biodegradable and antimicrobial waterborne polyurethane dispersions (PUDs) and their casted solid films have recently emerged as important alternatives to their solvent-based and non-biodegradable counterparts for various applications due to their versatility, health, and environmental friendliness. The nanoscale morphology of the PUDs, dispersion stability, and the thermomechanical properties of the solid films obtained from the solvent cast process are strongly dependent on several important parameters, such as the preparation method, polyols, diisocyanates, solid content, chain extension, and temperature. The biodegradability, biocompatibility, antimicrobial properties and biomedical applications can be tailored based on the nature of the polyols, polarity, as well as structure and concentration of the internal surfactants (anionic or cationic). This review article provides an important quantitative experimental basis and structure evolution for the development and synthesis of biodegradable waterborne PUDs and their solid films, with prescribed macromolecular properties and new functions, with the aim of understanding the relationships between polymer structure, properties, and performance. The review article will also summarize the important variables that control the thermomechanical properties and biodegradation kinetics, as well as antimicrobial and biocompatibility behaviors of aqueous PUDs and their films, for certain industrial and biomedical applications.


Asunto(s)
Antiinfecciosos/química , Plásticos Biodegradables/química , Polímeros/química , Poliuretanos/química , Aniones/química , Aniones/uso terapéutico , Antiinfecciosos/uso terapéutico , Plásticos Biodegradables/uso terapéutico , Humanos , Polímeros/uso terapéutico , Poliuretanos/uso terapéutico , Solventes/química , Tensoactivos/química , Tensoactivos/uso terapéutico , Agua/química
19.
Molecules ; 26(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670379

RESUMEN

A p-type thermoelectric conjugated polymer based on indacenodithiophene and benzothiadiazole is designed and synthesized by replacing normal aliphatic side chains (P1) with conjugated aromatic benzene substituents (P2). The introduced bulky substituent on P2 is detrimental to form the intensified packing of polymers, therefore, it hinders the efficient transporting of the charge carriers, eventually resulting in a lower conductivity compared to that of the polymers bearing aliphatic side chains (P1). These results reveal that the modification of side chains on conjugated polymers is crucial to rationally designed thermoelectric polymers with high performance.


Asunto(s)
Benceno/química , Compuestos Orgánicos/química , Polímeros/química , Centrales Eléctricas
20.
Molecules ; 26(4)2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33671148

RESUMEN

NaYF4:Er,Yb upconversion luminescent nanoparticles (UCNPs) were prepared by hydrothermal methods at 180 °C for 24 h. The X-ray diffraction (XRD) and TEM (transmission electron microscopy) images show that the resulting 60 nm UCNPs possess a hexagonal structure. In this work, maleic anhydride (MA) was grafted on the surface of UCNPs to induce hydrophilic properties. The photoluminescence spectra (PL) show upconversion emissions centered around 545 nm and 660 nm under excitation at 980 nm. The luminescent inks, including UCNPs@MA, polyvinyl alcohol (PVA), deionized water (DI), and ethylene glycol (EG), exhibit suitable properties for screen printing, such as high stability, emission intensity, and tunable dynamic viscosity. The printed patterns with a height of 5 mm and a width of 1.5 mm were clearly observed under the irradiation of a 980 nm laser. Our strategy provides a new route for the controlled synthesis of hydrophilic UCNPs, and shows that the UCNPs@MAs have great potential in applications of anti-counterfeiting packing.


Asunto(s)
Fluoruros/química , Tecnología Química Verde , Tinta , Luminiscencia , Anhídridos Maleicos/química , Nanopartículas/química , Análisis Espectral , Iterbio/química , Itrio/química , Erbio/química , Fenómenos Ópticos , Polímeros/química , Espectroscopía Infrarroja por Transformada de Fourier , Vibración , Difracción de Rayos X
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