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1.
Small ; 19(52): e2304996, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37635097

RESUMEN

Both ternary copolymerization and ternary blending are effective methods to fine-tune polymer structure and manipulate thin-film morphology to improve device performance. In this work, three D-A-A-A (D: donor, A: acceptor) terpolymer donors (FY1, FY2, and FY3) are synthesized by introducing BDD (1,3-bis(2-ethylhexyl)-5,7-di(thiophen-2-yl)benzo[1,2-c:4,5-c']dithiophene-4,8-dione) units into the D-A alternating copolymer PM6 backbone. Owing to the promoted conjugated planarity and excellent absorption of BDD, the obtained terpolymers display an extended absorption range and enhanced π-π stacking orientation, which is a promising third component in ternary device. As a result, the optimal FY1:PM6:BTP-eC9-based ternary device afforded an impressive power conversion efficiency (PCE) as high as 18.52%, owing to the efficient charge transport, negligible energy loss, and suitable domain size. The result provides an efficient method to obtain high-performance polymer solar cells by using analogous polymer donors in ternary device.

2.
Nano Lett ; 22(16): 6560-6566, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-35947031

RESUMEN

Cooling based on the electrocaloric effect (ECE) is a promising solution to environmental and energy efficiency problems of vapor-compression refrigeration. Ferroelectric polymer-ceramics nanocomposites, integrating high electric breakdown of organic ferroelectrics and large EC strength of ceramics, are attractive EC materials. Here, we tuned the orientation of Ba0.67Sr0.33TiO3 nanofibers (BST nfs) in the P(VDF-TrFE-CFE) polymer. When the nfs were aligned parallel to the field, a ΔT of 11.3 K with an EC strength of 0.16 K·m/MV was achieved in the blends. The EC strength not only surpasses advanced nanocomposites but also is comparable to ferroelectric ceramics. The simulation indicates that a significantly higher electric field is concentrated in polymer regions around the ends of the orientated nfs, contributing to easier flipping of polymer chains for large ECE. This work provides a new method to obtain large ECE in composites for next-generation refrigeration.

3.
Int J Mol Sci ; 24(20)2023 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-37894851

RESUMEN

New amphiphilic VP-(di)methacrylate terpolymers of different monomer compositions and topologies have been synthesized by radical polymerization in toluene without any growth regulator of polymer chains. Their structures and properties in solid state and water solution were studied by double-detector size-exclusion chromatography; IR-, 1H, and 13C NMR-spectroscopy; DLS, TEM, TG, and DSC methods. The composition of the VP-AlkMA-TEGDM monomer mixture has been established to regulate the topology of the resulting macromolecules. The studied terpolymers presented on TEM images as individual low-contrast particles and their conglomerates of various sizes with highly ordered regions; in general, they are amorphous structures. None of the terpolymers demonstrated cytotoxic effects for noncancerous Vero and tumor HeLa cells. Hydrophobic D-α-tocopherol (TP) was encapsulated in terpolymer nanoparticles (NPs), and its antioxidant activity was evaluated by ABTS (radical monocation 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid)) or DPPH (2,2'-diphenyl-1-picrylhydrazyl) methods. The reaction efficiency depends on the TP-NP type. The IC50 values for the decolorization reaction of ABTS•+ and DPPH inhibition in the presence of initial and encapsulated TP were obtained.


Asunto(s)
Antioxidantes , Polímeros , Humanos , Células HeLa , Antioxidantes/farmacología , Antioxidantes/química , Polímeros/química
4.
Mikrochim Acta ; 189(8): 277, 2022 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-35829791

RESUMEN

A new polymeric (methyl methacrylate/ethylene glycol dimethacrylate/1,2-epoxy-5-hexene) base/matrix has been fabricated and decorated with zwitterionic hydrophilic cysteic acid (Cya) for the enrichment of intact N-glycopeptides from standards and biological samples. Terpolymer-Cya provides good enrichment efficiency, improved hydrophilicity, and selectivity by virtue of better surface area (2.09 × 102 m2/g) provided by terpolymer and the zwitterionic property offered by cysteic acid. Cysteic acid-functionalized polymeric hydrophilic interaction liquid chromatography (HILIC) sorbent enriches 35 and 24 N-linked glycopeptides via SPE (solid phase extraction) mode from tryptic digests of model glycoproteins, i.e., immunoglobulin G (IgG) and horseradish peroxidase (HRP), respectively. Zwitterionic chemistry of cysteine helps in achieving higher selectivity with BSA digest (1:200), and lower detection limit down to 100 attomoles with a complete glycosylation profile of each standard digest. The recovery of 81% and good reproducibility define the application of terpolymer-Cya for complex samples like a serum. Analysis of human serum provides a profile of 807 intact N-linked glycopeptides via nano-liquid chromatography-tandem mass spectrometry (nLC-MS/MS). To the best of our knowledge, this is the highest number of glycopeptides enriched by any HILIC sorbent. Selected glycoproteins are evaluated in link to various cancers including the breast, lung, uterine, and melanoma using single-nucleotide variances (BioMuta). This study represents the complete idea of using an in-house developed strategy as a successful tool to help analyze, relate, and answer glycoprotein-based clinical issues regarding cancers.


Asunto(s)
Ácido Cisteico , Glicopéptidos , Glicopéptidos/análisis , Glicoproteínas , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem
5.
J Appl Biomed ; 20(3): 87-97, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36218129

RESUMEN

The aim of this study was to assess 17-ß-estradiol (E2) influence on sciatic nerve regeneration after injury followed by a repair with chitosan conduit in ovariectomized female rats. The study was performed in 2 groups (n = 16) of rats: OVChit - after excision of a fragment of the sciatic nerve, a chitosan conduit was implanted; OVChitE10 group - additionally to chitosan conduit, shape-memory terpolymer rods based on poly(L-lactide-co-glycolide- co-trimethylene carbonate) releasing 17-ß-estradiol for 20 weeks were implanted. The mean number of regenerating axons and mean fiber area were significantly greater in 17-ß-estradiol-treated animals. In this group, the infiltrate of leukocytes was diminished. The presence of 17-ß-estradiol receptors alpha and beta in motoneurons in the spinal cord were discovered. This may indicate the location where 17-ß-estradiol affects the regeneration of the injured nerve. Estradiol released from the terpolymer rods for 20 weeks could enhance, to some extent, sciatic nerve regeneration after injury, and diminish the inflammatory reaction. In the future, 17-ß-estradiol entrapped in terpolymer rods could be used in the repair of injured peripheral nerves, but there is a need for further studies.


Asunto(s)
Quitosano , Animales , Quitosano/farmacología , Estradiol/farmacología , Femenino , Regeneración Nerviosa , Ratas , Ratas Wistar , Receptores de Estradiol , Nervio Ciático/cirugía
6.
Br J Community Nurs ; 27(6): 280-286, 2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35671211

RESUMEN

Skin excoriation is a common complication of enteral tube feeding; however, universal guidelines for treatment do not exist. A quality improvement pilot study to inform the development of a local clinical care pathway was conducted. The enteral nutrition team identified products and assessed patient preference, ease of use, availability, and clinical outcomes for inclusion. This pathway includes gentle site cleansing followed by skin protectant application. For mild skin excoriation (<5 mm), acrylate terpolymer barrier film (3M Cavilon No Sting Barrier Film) was applied once every seven days. Moderate skin excoriation (5-20 mm) received acrylate terpolymer barrier film twice a day for seven days. Severe skin excoriation (>20 mm) received advanced elastomeric skin protectant (3M Cavilon Advanced Skin Protectant) applied once every 3-4 days for 2-4 weeks. Ten patients were included, three were selected for discussion. Adoption of this local clinical care pathway resulted in skin healing and improved patient comfort.


Asunto(s)
Vías Clínicas , Nutrición Enteral , Acrilatos , Humanos , Proyectos Piloto , Mejoramiento de la Calidad
7.
Angew Chem Int Ed Engl ; 60(37): 20443-20451, 2021 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-34121303

RESUMEN

Polymerizations of perfluorinated vinyl ethers (PFVEs) provide an important category of fluoropolymers that have received considerable interests in applications. In this work, we report the development of an organocatalyzed controlled radical alternating terpolymerization of PFVEs and vinyl ethers (VEs) under visible-light irradiation. This method not only enables the synthesis of a broad scope of fluorinated terpolymers of low dispersities and high chain-end fidelity, facilitating tuning the chemical compositions by rationally choosing the type and/or ratio of comonomers, but also allows temporal control of chain-growth, as well as the preparation of a variety of novel fluorinated block copolymers. To showcase the versatility of this method, fluorinated alternating terpolymers have been synthesized and customized to simultaneously display a variety of desirable properties for solid polymer electrolyte design, creating new opportunities in high-performance energy storage devices.

8.
Angew Chem Int Ed Engl ; 60(8): 4315-4321, 2021 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-33180984

RESUMEN

Polymeric materials possessing both high refractive indices and high Abbe numbers are much in demand for the development of advanced optical devices. However, the synthesis of such functional materials is a challenge because of the trade-off between these two properties. Herein, a synthetic strategy is presented for enhancing the optical properties of CO2 -based polycarbonates by modifying the polymer's topological structure. Terpolymers with thiocarbonate and carbonate units randomly distributed in the polymers' main chain were synthesized via the terpolymerization of cyclohexene oxide with a mixture of CO2 and COS in the presence of metal catalysts, most notably a dinuclear aluminum complex. DFT calculations were employed to explain why different structural sequence were obtained with distinct bimetallic catalysts. Varying the CO2 pressure made it possible to obtain terpolymers with tunable carbonate linkages in the polymer chain. More importantly, optical property studies revealed that terpolymers with comparable thiocarbonate and carbonate units exhibited a refractive index of 1.501 with an enhanced Abbe number as high as 48.6, much higher than the corresponding polycarbonates or polythiocarbonates. Additionally, all terpolymers containing varying thiocarbonate content displayed good thermal properties with Tg >109 °C and Td >260 °C, suggesting little loss in the thermal stability compared to the polycarbonate. Hence, modification of the topological structure of the polycarbonate is an efficient method of obtaining polymeric materials with enhanced optical properties without compromising thermal performance.

9.
Mikrochim Acta ; 187(10): 555, 2020 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-32910214

RESUMEN

A hydrophilic terpolymer MOF composite is designed with high surface area and porosity to enrich mono- and multi-glycosylated peptides facilitating a bottom-up approach. Terpolymer@ZIF-8 is synthesized using free radical polymerization followed by layer by layer ZIF-8 fabrication. Subsequent surface modification was made by aminophenylboronic acid (AMBA). The enrichment ability of terpolymer@ZIF-8@BA is evaluated by using tryptic digest of IgG and HRP to exemplify mono- and multi-glycosylated protein samples. Improved selectivity of 1:200 for spiked HRP in BSA digest and sensitivity down to 1 fmol µL-1 is achieved. Batch to batch reproducibility is better 1% RSD which favors the adoption of the developed method for routine N-linked glycopeptide/protein determination. Cost-effective nature of given approach is given by regeneration of the material up to four cycles. Total 318 N-linked glycopeptides have been identified from 1 µL human serum digest after subjecting the enriched and PNGase-treated deglycosylated peptides to LC-MS. Thus, terpolymer@ZIF-8@BA holds the potential both for mono- and multi-glycosylated peptides from complex biological sample. Graphical abstract.


Asunto(s)
Glicopéptidos/metabolismo , Espectrometría de Masas/métodos , Péptidos/metabolismo
10.
Bioprocess Biosyst Eng ; 40(11): 1643-1656, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28762009

RESUMEN

This study reports an efficient fed-batch strategy to improve poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-4-hydroxybutyrate) [P(3HB-co-3HV-co-4HB)] terpolymer production by Cupriavidus sp. USMAA2-4 with enhanced mechanical properties in bioreactor. The cultivations have been performed by combining oleic acid with γ-butyrolactone at different concentration ratios with 1-pentanol at a fixed concentration. The batch and fed-batch fermentations have resulted in P(3HB-co-3HV-co-4HB) with compositions of 9-35 mol% 3HV and 4-24 mol% 4HB monomers. The DO-stat fed-batch fermentation strategies have significantly improved the production with a maximum 4.4-fold increment of cell dry weight (CDW). Besides, appropriate feeding of the substrates has resulted in an increment of terpolymer productivity from 0.086-0.347 g/L/h, with a significantly shortened cultivation time. The bacterial growth and terpolymer formation have been found to be affected by the concentration of carbon sources supplied. Characterization of P(3HB-co-3HV-co-4HB) has demonstrated that incorporation of 3HV and 4HB monomer has significantly improved the physical and thermodynamic properties of the polymers, by reducing the polymer's crystallinity. The tensile strength, Young's modulus of the terpolymer has been discovered to increase with the increase of M w. The fed-batch fermentation strategies employed in this study have resulted in terpolymers with a range of flexible materials having improved tensile strength and Young's modulus as compared to the terpolymer produced from batch fermentation. Possession of lower melting temperature indicates an enhanced thermal stability which broadens the polymer processing window.


Asunto(s)
Reactores Biológicos , Ensayo de Materiales , Poliésteres/química , Rastreo Diferencial de Calorimetría , Cromatografía de Gases , Cromatografía en Gel , Fermentación , Resistencia a la Tracción , Termogravimetría
11.
Molecules ; 22(8)2017 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-28796171

RESUMEN

The presented paper concerns scientific research on processing a poly(lactide-co-glycolide-co-trimethylene carbonate) copolymer (PLLAGLTMC) with thermally induced shape memory and a transition temperature around human body temperature. The material in the literature called terpolymer was used to produce smart, nonwoven fabric with the melt blowing technique. Bioresorbable and biocompatible terpolymers with shape memory have been investigated for its medical applications, such as cardiovascular stents. There are several research studies on shape memory in polymers, but this phenomenon has not been widely studied in textile products made from shape memory polymers (SMPs). The current research aims to explore the characteristics of the PLLAGLTMC nonwoven fabric in detail and the mechanism of its shape memory behavior. In this study, the nonwoven fabric was subjected to thermo-mechanical, morphological, and shape memory analysis. The thermo-mechanical and structural properties were investigated by means of differential scanning calorimetry, dynamic mechanical analysis, scanning electron microscopic examination, and mercury porosimetry measurements. Eventually, the gathered results confirmed that the nonwoven fabric possessed characteristics that classified it as a smart material with potential applications in medicine.


Asunto(s)
Poliésteres/química , Materiales Biocompatibles , Humanos , Ensayo de Materiales/métodos , Porosidad , Temperatura , Textiles , Andamios del Tejido
12.
Des Monomers Polym ; 20(1): 406-418, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29491812

RESUMEN

Sharply thermo- and pH-responsive pentablock terpolymer with a core-shell-corona structure was prepared by RAFT polymerization of N-isopropylacrylamide and methacrylic acid monomers using PEG-based benzoate-type of RAFT agent. The PEG-based RAFT agent could be easily synthesized by dihydroxyl-capped PEG with 4-cyano-4-(thiobenzoyl) sulfanylpentanoic acids, using esterification reaction. This pentablock terpolymer was characterized by 1H NMR, FT-IR, and GPC. The PDI was obtained by GPC, indicating that the molecular weight distribution was narrow and the polymerization was well controlled. The thermo- and pH-responsive micellization of the pentablock terpolymer in aqueous solution was investigated using fluorescence spectroscopy technique, UV-vis transmittance, and TEM. The LCST of pentablock terpolymer increased (over 50 °C) compared to the NIPAM homopolymer (~32 °C), due to the incorporation of the hydrophilic PEG and PMA blocks in pentablock terpolymer (PNIPAM block as the core, PEG the block and the hydrophilic PMA block as the shell and the corona). Also, pH-dependent phase transition behavior shows at a pH value of about ~5.8, according to pKa of MAA. Thus, in acidic solution at room temperature, the pentablock terpolymer self-assembled to form core-shell-corona micelles, with the hydrophobic PMA block as the core, the PNIPAM block and the hydrophilic PEG block as the shell and the corona, respectively.

13.
Mol Pharm ; 13(12): 4021-4033, 2016 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-27809548

RESUMEN

In this study, we developed a micellar platform composed of terpolymers for the encapsulation of inorganic arsenite or arsenous acid (AsIII). For this purpose, a series of terpolymers composed of poly(ethylene oxide) (PEO, block A), poly(α-carboxylate-ε-carprolactone) (PCCL, block B), and poly(ε-caprolactone) (PCL, block C) with either a blocked, i.e., BC or CB, or random, i.e., (B/C)ran block copolymer sequence in the polyester segment was synthesized. The COOH groups on block B were further modified with mercaptohexylamine for AsIII encapsulation. We then investigated how sequence of terpolymers can affect the stability and surface charge of micelles as well as the cellular uptake of their cargo, i.e., AsIII, by MDA-MB-435 cancer cells. 1H NMR spectroscopy in D2O and CDCl3 was also used to study the structure of different terpolymer micelles. Our results showed micelles with ABC sequence to have better stability over those of ACB and A(B/C)ran as reflected by a lower critical micellar concentration. The AsIII-loaded ABC micelles were less negatively charged on the surface than the other two types of terpolymer micelles. In line with this observation, ABC micelles showed a substantially enhanced uptake of AsIII by MDA-MB-435 cancer cells. Stability and surface charge are key parameters that can influence the performance of polymeric micelles as nanodrug carriers. Based on these results, we suggest ABC micelles to have improved characteristics for AsIII delivery compared to ACB and A(B/C)ran micelles.


Asunto(s)
Antineoplásicos/farmacología , Arsénico/farmacología , Neoplasias de la Mama/metabolismo , Sistemas de Liberación de Medicamentos , Micelas , Polímeros/química , Antineoplásicos/química , Arsénico/química , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Humanos
14.
Macromol Rapid Commun ; 37(3): 209-14, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26641211

RESUMEN

A route of synthesizing triblock terpolymers in a one-pot, "one-step" polymerization approach is presented. The combination of two distinct polymerization techniques through orthogonal catalyst/initiator functionalities attached to a polymeric linker furnishes novel pathways to ABC-terpolymers. Both polymerizations have to be compatible regarding mechanisms, chosen monomers, and solvents. Here, an α,ω-heterobifunctional poly(ethylene glycol) serves as poly-meric catalyst/initiator to obtain triblock terpolymers of poly(norbornene)-b-poly(ethylene glycol)-b-poly(L-lactic acid) PNB-PEG-PLLA via simultaneous ring opening metathesis poly-merization and ring opening polymerization in a fast one-pot polymerization. Structural characterization of the polymers is provided via (1)H-, DOSY-, and (1)H,(1)H-COSY-NMR, while solution and thin film self-assembly are investigated by dynamic light scattering and atomic force microscopy.


Asunto(s)
Polimerizacion , Polímeros/síntesis química , Alcohol Bencilo/síntesis química , Alcohol Bencilo/química , Hidrodinámica , Ácido Láctico/química , Ligandos , Microscopía Electrónica de Rastreo , Peso Molecular , Poliésteres , Polietilenglicoles/química , Polímeros/química
15.
Waste Manag Res ; 33(5): 453-9, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25750055

RESUMEN

In the present research, blending of polymers used in electrical and electronic equipment, i.e. acrylonitrile-butadiene-styrene terpolymer, polycarbonate and polypropylene, was performed in a twin-screw extruder, in order to explore the effect process parameters on the mixture properties, in an attempt to determine some characteristics of a fast and economical procedure for waste management. The addition of polycarbonate in acrylonitrile-butadiene-styrene terpolymer seemed to increase its thermal stability. Also, the addition of polypropylene in acrylonitrile-butadiene-styrene terpolymer facilitates its melt processing, whereas the addition of acrylonitrile-butadiene-styrene terpolymer in polypropylene improves its mechanical performance. Moreover, the upgrading of the above blends by incorporating 2 phr organically modified montmorillonite was investigated. The prepared nanocomposites exhibit greater tensile strength, elastic modulus and storage modulus, as well as higher melt viscosity, compared with the unreinforced blends. The incorporation of montmorillonite nanoplatelets in polycarbonate-rich acrylonitrile-butadiene-styrene terpolymer/polycarbonate blends turns the thermal degradation mechanism into a two-stage process. Alternatively to mechanical recycling, the energy recovery from the combustion of acrylonitrile-butadiene-styrene terpolymer/polycarbonate and acrylonitrile-butadiene-styrene terpolymer/polypropylene blends was recorded by measuring the gross calorific value. Comparing the investigated polymers, polypropylene presents the higher gross calorific value, followed by acrylonitrile-butadiene-styrene terpolymer and then polycarbonate. The above study allows a rough comparative evaluation of various methodologies for treating plastics from waste from electrical and electronic equipment.


Asunto(s)
Residuos Electrónicos/análisis , Plásticos/análisis , Polímeros/análisis , Reciclaje/métodos , Administración de Residuos/métodos , Plásticos/química , Polímeros/química
16.
Macromol Rapid Commun ; 35(4): 437-41, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24347368

RESUMEN

Diblock brush terpolymers (DBTs) with different fluorinated methacrylate-based block segments are synthesized through sequential ring-opening metathesis polymerizations and are used to prepare polymer thin films with predictable film thicknesses. These DBTs exhibit preferable substrate vertical alignments within the films, induced by the relatively lower surface energy of the fluorinated structural components, together with the overall cylindrical morphology of the brush architecture.


Asunto(s)
Polímeros/química , Metacrilatos/química , Nanotecnología , Polimerizacion , Polímeros/síntesis química
17.
J Biomater Appl ; 39(1): 66-79, 2024 07.
Artículo en Inglés | MEDLINE | ID: mdl-38646887

RESUMEN

Three-dimensional (3D) structures are actually the state-of-the-art technique to create porous scaffolds for tissue engineering. Since regeneration in cartilage tissue is limited due to intrinsic cellular properties this study aims to develop and characterize three-dimensional porous scaffolds of poly (L-co-D, L lactide-co-trimethylene carbonate), PLDLA-TMC, obtained by 3D fiber deposition technique. The PLDLA-TMC terpolymer scaffolds (70:30), were obtained and characterized by scanning electron microscopy, gel permeation chromatography, differential scanning calorimetry, thermal gravimetric analysis, compression mechanical testing and study on in vitro degradation, which showed its amorphous characteristics, cylindrical geometry, and interconnected pores. The in vitro degradation study showed significant loss of mechanical properties compatible with a decrease in molar mass, accompanied by changes in morphology. The histocompatibility association of mesenchymal stem cells from rabbit's bone marrow, and PLDLA-TMC scaffolds, were evaluated in the meniscus regeneration, proving the potential of cell culture at in vivo tissue regeneration. Nine New Zealand rabbits underwent total medial meniscectomy, yielding three treatments: implantation of the seeded PLDLA-TMC scaffold, implantation of the unseeded PLDLA-TMC and negative control (defect without any implant). After 24 weeks, the results revealed the presence of fibrocartilage in the animals treated with polymer. However, the regeneration obtained with the seeded PLDLA-TMC scaffolds with mesenchymal stem cells had become intimal to mature fibrocartilaginous tissue of normal meniscus both macroscopically and histologically. This study demonstrated the effectiveness of the PLDLA-TMC scaffold in meniscus regeneration and the potential of mesenchymal stem cells in tissue engineering, without the use of growth factors. It is concluded that bioresorbable polymers represent a promising alternative for tissue regeneration.


Asunto(s)
Dioxanos , Células Madre Mesenquimatosas , Poliésteres , Impresión Tridimensional , Ingeniería de Tejidos , Andamios del Tejido , Animales , Conejos , Andamios del Tejido/química , Células Madre Mesenquimatosas/citología , Dioxanos/química , Poliésteres/química , Ingeniería de Tejidos/métodos , Materiales Biocompatibles/química , Menisco/citología , Regeneración , Trasplante de Células Madre Mesenquimatosas/métodos , Porosidad , Ensayo de Materiales , Implantes Absorbibles , Células Cultivadas , Polímeros/química
18.
ACS Appl Mater Interfaces ; 16(11): 14026-14037, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38447136

RESUMEN

With the rapid development of small-molecule electron acceptors, polymer electron donors are becoming more important than ever in organic photovoltaics, and there is still room for the currently available high-performance polymer donors. To further develop polymer donors with finely tunable structures to achieve better photovoltaic performances, random ternary copolymerization is a useful technique. Herein, by incorporating a new electron-withdrawing segment 2,3-bis(3-octyloxyphenyl)dithieno[3,2-f:2',3'-h]quinoxaline derivative (C12T-TQ) to PM6, a series of terpolymers were synthesized. It is worth noting that the introduction of the C12T-TQ unit can deepen the highest occupied molecular orbital energy levels of the resultant polymers. In addition, the polymer Z6 with a 10% C12T-TQ ratio possesses the highest film absorption coefficient (9.86 × 104 cm-1) among the four polymers. When blended with Y6, it exhibited superior miscibility and mutual crystallinity enhancement between Z6 and Y6, suppressed recombination, better exciton separation and charge collection characteristics, and faster hole transfer in the D-A interface. Consequently, the device of Z6:Y6 successfully achieved enhanced photovoltaic parameters and yielded an efficiency of 17.01%, higher than the 16.18% of the PM6:Y6 device, demonstrating the effectiveness of the meta-octyloxy-phenyl-modified dithieno[3,2-f:2',3'-h]quinoxaline moiety to build promising terpolymer donors for high-performance organic solar cells.

19.
Acta Pharm Sin B ; 14(6): 2669-2684, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38828156

RESUMEN

Solid oral controlled release formulations feature numerous clinical advantages for drug candidates with adequate solubility and dissolution rate. However, most new chemical entities exhibit poor water solubility, and hence are exempt from such benefits. Although combining drug amorphization with controlled release formulation is promising to elevate drug solubility, like other supersaturating systems, the problem of drug recrystallization has yet to be resolved, particularly within the dosage form. Here, we explored the potential of an emerging, non-leachable terpolymer nanoparticle (TPN) pore former as an internal recrystallization inhibitor within controlled release amorphous solid dispersion (CRASD) beads comprising a poorly soluble drug (celecoxib) reservoir and insoluble polymer (ethylcellulose) membrane. Compared to conventional pore former, polyvinylpyrrolidone (PVP), TPN-containing membranes exhibited superior structural integrity, less crystal formation at the CRASD bead surface, and greater extent of celecoxib release. All-atom molecular dynamics analyses revealed that in the presence of TPN, intra-molecular bonding, crystal formation tendency, diffusion coefficient, and molecular flexibility of celecoxib were reduced, while intermolecular H-bonding was increased as compared to PVP. This work suggests that selection of a pore former that promotes prolonged molecular separation within a nanoporous controlled release membrane structure may serve as an effective strategy to enhance amorphicity preservation inside CRASD.

20.
Heliyon ; 9(10): e20459, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37810859

RESUMEN

In an innovative approach to push the boundaries of antimicrobial and antioxidant strategies, we present the synthesis and characterization of a novel terpolymer derived from N-Phenyl-p-phenylenediamine and 2-aminopyrimidine with formaldehyde in the presence of dimethylformamide as a reaction medium through polycondensation technique. Leveraging this terpolymer as a ligand, we introduce an intriguing terpolymer-metal complex, created with Ni (II) metal ion. In our pursuit to validate the structure and properties of these substances, we performed meticulous characterizations using important spectral studies such as FTIR, electronic, and 1H NMR spectroscopy. This provided us with a unique fingerprint for the (N-Phenyl-p-phenylenediamine-2-aminopyrimidine-formaldehyde) terpolymeric ligand (PAF) and its metal complex. In addition, the molecular weights of PAF terpolymer were established using gel permeation chromatography. Upon investigation, PAF terpolymer and PAF-Ni complex exhibited impressive antimicrobial activity, tested by the disc-diffusion technique. Both demonstrated potency against a range of harmful bacterial and fungal strains, including Staphylococcus aureus, Escherichia coli, Candida albicans, and Aspergillus niger. In an extension to their biological applications, we evaluated the free radical scavenging activity of PAF terpolymer and PAF-Ni complex using the DPPH assay. The complex PAF-Ni showcased an enhanced scavenging activity 73.94% (IC50 = 17.58) compared to the ligand PAF 63.06% (IC50 = 27.61) at 100 µg/ml indicating its potential role in oxidative stress management.

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