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1.
Sci Rep ; 14(1): 10825, 2024 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-38734808

RESUMEN

This study developed a kind of PEG-crosslinked O-carboxymethyl chitosan (O-CMC-PEG) with various PEG content for food packaging. The crosslinking agent of isocyanate-terminated PEG was firstly synthesized by a simple condensation reaction between PEG and excess diisocyanate, then the crosslink between O-carboxymethyl chitosan (O-CMC) and crosslinking agent occurred under mild conditions to produce O-CMC-PEG with a crosslinked structure linked by urea bonds. FT-IR and 1H NMR techniques were utilized to confirm the chemical structures of the crosslinking agent and O-CMC-PEGs. Extensive research was conducted to investigate the impact of the PEG content (or crosslinking degree) on the physicochemical characteristics of the casted O-CMC-PEG films. The results illuminated that crosslinking and components compatibility could improve their tensile features and water vapor barrier performance, while high PEG content played the inverse effects due to the microphase separation between PEG and O-CMC segments. The in vitro degradation rate and water sensitivity primarily depended on the crosslinking degree in comparison with the PEG content. Furthermore, caused by the remaining -NH2 groups of O-CMC, the films demonstrated antibacterial activity against Escherichia coli and Staphylococcus aureus. When the PEG content was 6% (medium crosslinking degree), the prepared O-CMC-PEG-6% film possessed optimal tensile features, high water resistance, appropriate degradation rate, low water vapor transmission rate and fine broad-spectrum antibacterial capacity, manifesting a great potential for application in food packaging to extend the shelf life.


Asunto(s)
Antibacterianos , Quitosano , Escherichia coli , Embalaje de Alimentos , Polietilenglicoles , Quitosano/química , Quitosano/análogos & derivados , Quitosano/farmacología , Embalaje de Alimentos/métodos , Antibacterianos/química , Antibacterianos/farmacología , Polietilenglicoles/química , Escherichia coli/efectos de los fármacos , Reactivos de Enlaces Cruzados/química , Espectroscopía Infrarroja por Transformada de Fourier , Staphylococcus aureus/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Resistencia a la Tracción
2.
Int J Biol Macromol ; 256(Pt 1): 128441, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38013081

RESUMEN

This study focused on the development of cross-linked poly(ester urethane)/starch (PEUST) composites containing 50 wt% starch content for food-packaging materials. The NCO-terminated poly(caprolactone-urethane) prepolymer (PCUP) was first synthesized through bulk condensation. Then, low-moisture starch (0.21 wt%) and PCUP-based PEUST films were fabricated through an intensive extrusion process, followed by thermo-compression molding. The chemical structure of PCUP and PEUST was confirmed using Fourier transform infrared spectroscopy. Moreover, a comprehensive evaluation was conducted to assess the influence of cross-link density on the physicochemical properties of the composite films. The results showed that an increase in the cross-link density within the composites improved component compatibility and tensile strength but reduced crystallinity, water sensitivity, hydrolytic degradability, and water vapor permeability (WVP) of the films. In addition, the cytotoxicity tests were conducted to evaluate the safety of the composite films, and the high cell viability demonstrated non-toxicity for food application. The PEUST-II films with moderate cross-link density exhibited a suitable degradation rate (27.7 % weight loss at degradation for 140 d), optimal tensile properties (tensile strength at break: 12.4 MPa; elongation at break: 352 %), and low WVP (68.4 g/(m2⋅24h) at 30 % relative humidity). These characteristics make them highly promising as fresh-keeping food packaging.


Asunto(s)
Embalaje de Alimentos , Poliésteres , Almidón , Almidón/química , Ésteres , Poliuretanos/química , Permeabilidad
3.
Biomacromolecules ; 24(7): 3327-3344, 2023 07 10.
Artículo en Inglés | MEDLINE | ID: mdl-37366605

RESUMEN

Uncontrolled bleeding in emergency situations is a great threat to both military and civilian lives, and an ideal hemostat for effectively controlling prehospital hemorrhage is urgently needed but still lacking. Although hemostatic hydrogels are promising for emergency hemostasis, they are currently challenged by either the mutual exclusion between a short gelation time and strong adhesive network or the insufficient functionality of ingredients and complicated operations for in situ curing. Herein, an extracellular matrix biopolymer-based and multifunctional hemostatic hydrogel that simultaneously integrates rapid thermoresponsive gelation, robust wet adhesion, and ease of use in emergencies is rationally engineered. This hydrogel can be conveniently used via simple injection and achieves instant sol-gel phase transition at body temperature. Its comprehensive performance could be facilely regulated by tuning the proportions of components, and the optimal performance (gelation time 6-8 s, adhesion strength 125 ± 3.6 kPa, burst pressure 282 ± 4.1 mmHg) is established due to the coordinated enhancement of the photo-cross-linking pretreatment and the hydrophilic-hydrophobic balance among various interactions in the hydrogel system. Additionally, it exhibits significant coagulation effect in vitro and enables effective hemostasis and wound healing in vivo. This work provides a promising platform for versatile applications of hydrogel-based materials, including emergency hemostasis.


Asunto(s)
Hemostáticos , Hidrogeles , Hidrogeles/farmacología , Hidrogeles/química , Hemostáticos/farmacología , Biomimética , Hemostasis , Coagulación Sanguínea
4.
J Mater Chem B ; 11(25): 5846-5855, 2023 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-37291983

RESUMEN

This work developed innovative poly(ester-urethane) materials double-modified by quercetin (QC) and phosphorylcholine (PC) with improved antibacterial activity and hemocompatibility. The functional monomer of PC-diol was first synthesized via a click reaction between 2-methacryloyloxyethyl phosphorylcholine and α-thioglycerol; the NCO-terminated prepolymer was subsequently prepared by a one-pot condensation method of PC-diol, poly(ε-caprolactone) diol, and excess isophorone diisocyanate; finally, the prepolymer was chain-extended with QC to produce the linear products (PEU-PQs). 1H NMR, FT-IR, and XPS techniques confirmed the successful introduction of PC and QC, and the in-depth characterization of the cast PEU-PQ films was carried out. Although a low crystallinity was demonstrated by XRD and thermal analysis, the films exhibited excellent tensile stress and stretchability due to the interchain multiple hydrogen bonds. The introduction of PC groups enhanced the surface hydrophilicity, water absorption, and the in vitro hydrolytic degradation rate of the film materials. Inhibition zone tests presented that the QC-based PEU-PQs had effective antibacterial activity against E. coli and S. aureus. The biological evaluations of the materials were performed in vitro by protein absorption, platelet adhesion, and cytotoxic test and in vivo by subcutaneous implantation, which demonstrated superior surface hemocompatibility and biocompatibility. Collectively, the PEU-PQ biomaterials hold a prospective application in durable blood-contacting devices.


Asunto(s)
Poliuretanos , Quercetina , Poliuretanos/farmacología , Poliuretanos/química , Espectroscopía Infrarroja por Transformada de Fourier , Fosforilcolina/farmacología , Fosforilcolina/química , Ésteres , Escherichia coli , Staphylococcus aureus
5.
Molecules ; 28(8)2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37110535

RESUMEN

In this paper, an imine-based porous 3D covalent organic polymer (COP) was synthesized via solvothermal condensation. The structure of the 3D COP was fully characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and powder X-ray diffractometry, thermogravimetric analysis, and Brunauer-Emmer-Teller (BET) nitrogen adsorption. This porous 3D COP was used as a new sorbent for the solid-phase extraction (SPE) of amphenicol drugs, including chloramphenicol (CAP), thiamphenicol (TAP), and florfenicol (FF) in aqueous solution. Factors were investigated for their effects on the SPE efficiency, including the types and volume of eluent, washing speed, pH, and salinity of water. Under the optimized conditions, this method gave a wide linear range (0.1-200 ng/mL) with a high correlation coefficient value (R2 > 0.99), low limits of detection (LODs, 0.01-0.03 ng/mL), and low limits of quantification (LOQs, 0.04-0.10 ng/mL). The recoveries ranged from 83.98% to 110.7% with RSDs ≤ 7.02%. The good enrichment performance for this porous 3D COP might contribute to the hydrophobic and π-π interactions, the size-matching effect, hydrogen bonding, and the good chemical stability of 3D COP. This 3D COP-SPE method provides a promising approach to selectively extract trace amounts of CAP, TAP, and FF in environmental water samples in ng quantities.

6.
ACS Omega ; 6(21): 13915-13925, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34095683

RESUMEN

In this work, the effects of droplet size and reaction time on the adsorption-reaction processes between gelatin and α-[3-(2,3-epoxypropoxy) propyl]-ω-butyl-polydimethylsiloxane (PDMS-E) emulsion droplets were studied. Gelatin molecules were only physically adsorbed on the surface of the PDMS-E droplet in the 0-75 min range, which was unrelated to the droplet size (100-1000 nm). For the small-size droplets (<410 nm), the physical adsorption proceeded over 75 min followed by agglomeration. For middle-size droplets (410-680 nm), the physical adsorption finished at 125 min; subsequently, the nucleophilic reaction between the primary amino group and the epoxy group began to happen, and globular-like or core-shell colloidal particles were formed. For large-size droplets (>680 nm), the nucleophilic reaction occurred at 75 min and produced core-shell or multi-layered colloidal particles. In a word, the physical absorption or nucleophilic reaction between gelatin and PDMS-E emulsion droplets could be controlled by controlling the droplet size and reaction time. Furthermore, the soft tissue paper coated with large-size droplets exhibited excellent resistance to water permeability and flame-resistant performance, which were carried out by water resistance and flammability tests.

7.
Membranes (Basel) ; 11(1)2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-33406798

RESUMEN

In the paper, the chitooligosaccharide (CHO) was surface-grafted on the medical segmented poly(ester-urethane) (SPU) film by a facile two-step procedure to improve the surface biocompatibility. By chemical treatment of SPU film with hexamethylene diisocyanate under mild reaction condition, free -NCO groups were first introduced on the surface with high grafting density, which were then coupled with -NH2 groups of CHO to immobilize CHO on the SPU surface (SPU-CHO). The CHO-covered surface was characterized by FT-IR and water contact angle test. Due to the hydrophilicity of CHO, the SPU-CHO possessed higher surface hydrophilicity and faster hydrolytic degradation rate than blank SPU. The almost overlapping stress-strain curves of SPU and SPU-CHO films demonstrated that the chemical treatments had little destruction on the intrinsic properties of the substrate. In addition, the significant inhibition of platelet adhesion and protein adsorption on CHO-covered surface endowed SPU-CHO an outstanding surface biocompatibility (especially blood compatibility). These results indicated that the CHO-grafted SPU was a promising candidate as blood-contacting biomaterial for biomedical applications.

8.
Nanoscale Horiz ; 6(2): 120-131, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33206735

RESUMEN

Photosensitizer-based photodynamic therapy (PDT) can not only kill tumor cells by the generated cytotoxic reactive oxygen species (ROS), but also trigger immunogenic cell death (ICD) and activate an immune response for immunotherapy. However, such photodynamic immunotherapy suffers from major obstacles in the tumor microenvironment. The hypoxic microenvironment greatly weakens PDT, while the immunosuppressive tumor microenvironment caused by aberrant tumor blood vessels and indoleamine 2,3-dioxygenase (IDO) leads to a significant reduction in immunotherapy. To overcome these obstacles, herein, an engineered photosensitizer nanoplatform is designed for amplified photodynamic immunotherapy by integrating chlorin e6 (Ce6, a photosensitizer), axitinib (AXT, a tyrosine kinase inhibitor) and dextro-1-methyl tryptophan (1MT, an IDO inhibitor). In our nanoplatform, AXT improves the tumor microenvironment by normalizing tumor blood vessels, which not only promotes PDT by reducing the level of hypoxia of the tumor microenvironment, but also promotes immunotherapy through facilitating infiltration of immune effector cells into the tumor and reversing the immunosuppressive effect of vascular endothelial growth factor (VEGF). Moreover, 1MT effectively inhibits the activity of IDO, further reducing the immunosuppressive nature of the tumor microenvironment. Therefore, this nanoplatform demonstrates an amplified photodynamic immunotherapy via tumor microenvironment modulation, exhibiting outstanding therapeutic efficacy against tumor growth and metastasis with negligible side toxicity. The current concept of engineering photosensitizer nanoplatforms for overcoming photodynamic immunotherapy obstacles provides a promising strategy against tumors.


Asunto(s)
Antineoplásicos/uso terapéutico , Inmunidad/efectos de los fármacos , Nanopartículas/uso terapéutico , Neoplasias/tratamiento farmacológico , Fármacos Fotosensibilizantes/uso terapéutico , Microambiente Tumoral/efectos de los fármacos , Animales , Axitinib/uso terapéutico , Clorofilidas , Células Dendríticas/efectos de los fármacos , Inhibidores Enzimáticos/uso terapéutico , Femenino , Inmunoterapia , Indolamina-Pirrol 2,3,-Dioxigenasa/antagonistas & inhibidores , Luz , Ratones Endogámicos C57BL , Neoplasias/terapia , Fotoquimioterapia , Fármacos Fotosensibilizantes/efectos de la radiación , Porfirinas/efectos de la radiación , Porfirinas/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Triptófano/análogos & derivados , Triptófano/uso terapéutico
9.
Mater Sci Eng C Mater Biol Appl ; 109: 110571, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32228944

RESUMEN

In order to improve the hemocompatibility of durable medical-grade polyurethane, a novel series of segmented poly(ester-urethane)s containing uniformly sized hard segments and phosphorylcholine (PC) groups on the side chains (SPU-PCs) was prepared by a facile method. The 2-methacryloyloxyethyl phosphorylcholine (MPC) was first reacted with α-thioglycerol by Michael addition to give a diol compound (MPC-diol), then the SPU-PCs with various PC content were prepared by a one-step chain extension of the mixture of MPC-diol and poly(ε-caprolactone) diol (PCL-diol) with aliphatic diurethane diisocyanates (HBH). The chemical structures of MPC-diol and SPU-PCs were confirmed by 1H NMR and FT-IR, and the influences of PC content on the physicochemical properties of the SPU-PC films were studied. The introduction of PC groups enhanced the degree of micro-phase separation and improved the hydrolytic degradation of the films. Due to the denser hydrogen bonds formed in the uniformly sized hard segments, the films exhibited favorable tensile properties and a slow hydrolytic degradation rate. The results of water contact angle and XPS analysis indicated that the PC groups on the flexible side chains were concentrated on the surface after contact with water. The surface hemocompatibility of the films was evaluated by testing the protein adsorption and platelet adhesion, and the results revealed that the films surfaces could dramatically suppress the protein adsorption and platelet adhesion. The PC-containing polyurethane films possessed outstanding tensile properties, low degradation rate and good surface hemocompatibility, implying their great potential for use as long-term implant or blood-contacting devices.


Asunto(s)
Plaquetas/metabolismo , Ensayo de Materiales , Fosforilcolina , Adhesividad Plaquetaria , Poliésteres , Poliuretanos , Plaquetas/citología , Humanos , Fosforilcolina/química , Fosforilcolina/farmacología , Poliésteres/síntesis química , Poliésteres/química , Poliésteres/farmacología , Poliuretanos/síntesis química , Poliuretanos/química , Poliuretanos/farmacología
10.
J Hazard Mater ; 383: 121142, 2020 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-31639610

RESUMEN

Leather wastewater is one of the most polluting industrial emissions. The efficiency of wastewater remediation is limited by its complex composition. Herein, a novel strategy for designing modified gelatine with higher degree of quaternization (MG-2) is presented. The higher degree of quaternization allows sufficient adsorption of dyes in the tanning process. It is an in situ, environmentally friendly, and innovative strategy to limit dye emissions and can circumvent the subsequent waste management. Dyes such as Direct Purple N and Acid Black 24 could be adsorbed completely within 5 min by the MG-2 film formed from MG-2 solution. In addition, a remarkable efficiency in removing Acid Red 73, Golden Orange G, and Acid Orange II (>96.1% removal rates) was achieved within 30 min. The adsorption equilibrium data suggested that the adsorption capacity was positively correlated to the concentration of MG-2. When Acid Orange II and MG-2 were used in the industrial re-tanning process, the residual dye concentration in wastewater was only 23.1 mg L-1, indicating that MG-2 is a promising re-tanning agent for adsorbing dyes in the leather tanning process.

11.
Mater Sci Eng C Mater Biol Appl ; 104: 109952, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31499985

RESUMEN

The aim of this work is to provide a new kind of polyurethane with improved surface blood compatibility for long-term blood-contacting biomaterials. In the study, an aliphatic poly(ester-urethane) (H-PEU) with uniform-size hard segments was synthesized by one-step chain extension of poly(ε-caprolactone) (PCL) with diurethane diisocyanate (HBH), and biomimetic phosphorylcholine (PC) groups were immobilized onto the film surface with high grafting efficiency by three-step chemical treatments under mild reaction conditions. The H-PEU film was firstly treated with 1,6-hexanediisocyanate (HDI) to introduce -NCO groups on the surface (H-PEU-NCO) through an allophanate reaction; the -NCO groups were then coupled via a condensation reaction with one of -NH2 groups of tris(2-aminoethyl)amine (TAEA) to immobilize -NH2 on the surface (H-PEU-NH2); finally, the double bond of 2-methacryloyloxyethyl phosphorylcholine (MPC) reacted with -NH2 by Michael addition reaction to obtain MPC-grafted H-PEU (H-PEU-MPC). The modified surfaces were characterized by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). The results verified that MPC was successfully grafted onto H-PEU surface with high grafting density. The blank and modified films showed similar crystallization behaviors, thermal stabilities and mechanical properties, indicating that the chemical treatments had minimum influence on the physicochemical properties of the substrate. The H-PEU-MPC displaying a much lower water contact angle (~15.2°) than H-PEU (80.3°) meant that the hydrophilic PC functional groups improved the surface hydrophilicity significantly. The surface blood compatibility was examined by bovine serum albumin adsorption and platelet adhesion tests, and the results revealed that H-PEU-MPC had improved resistance to protein adsorption and platelet adhesion capacity. The MPC-grafted H-PEU film possessed outstanding mechanical properties (ultimate stress: 36.1 MPa; strain at break: 883%), low protein adsorption quantity (1.33 µg/cm2) and good anti-platelet adhesion capacity (582 ±â€¯16 per mm2), implying its high potential to be applied as biomaterials for vascular grafts, subcutaneously implanted devices or other blood-contacting devices.


Asunto(s)
Materiales Biocompatibles/química , Metacrilatos/química , Fosforilcolina/análogos & derivados , Poliésteres/química , Poliuretanos/química , Adsorción/efectos de los fármacos , Animales , Caproatos/química , Isocianatos/química , Lactonas/química , Fosforilcolina/química , Adhesividad Plaquetaria/efectos de los fármacos , Conejos , Albúmina Sérica Bovina/química , Propiedades de Superficie
12.
Polymers (Basel) ; 11(6)2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31195671

RESUMEN

The aim of this study is to offer a new class of degradable shape-memory poly(ether-ester-urethane)s (SMPEEUs) based on poly(ether-ester) (PECL) and well-defined aliphatic diurethane diisocyanate (HBH) for further biomedical application. The prepolymers of PECLs were synthesized through bulk ring-opening polymerization using ε-caprolactone as the monomer and poly(ethylene glycol) as the initiator. By chain extension of PECL with HBH, SMPEEUs with varying PEG content were prepared. The chemical structures of the prepolymers and products were characterized by GPC, 1H NMR, and FT-IR, and the effect of PEG content on the physicochemical properties (especially the shape recovery properties) of SMPEEUs was studied. The microsphase-separated structures of the SMPEEUs were demonstrated by DSC and XRD. The SMPEEU films exhibited good tensile properties with the strain at a break of 483%-956% and an ultimate stress of 23.1-9.0 MPa. Hydrolytic degradation in vitro studies indicated that the time of the SMPEEU films becoming fragments was 4-12 weeks and the introduction of PEG facilitates the degradation rate of the films. The shape memory properties studies found that SMPEEU films with a PEG content of 23.4 wt % displayed excellent recovery properties with a recovery ratio of 99.8% and a recovery time of 3.9 s at body temperature. In addition, the relative growth rates of the SMPEEU films were greater than 75% after incubation for 72 h, indicating good cytocompatibility in vitro. The SMPEEUs, which possess not only satisfactory tensile properties, degradability, nontoxic degradation products, and cytocompatibility, but also excellent shape recovery properties at body temperature, promised to be an excellent candidate for medical device applications.

13.
J Biomater Sci Polym Ed ; 30(13): 1212-1226, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31140366

RESUMEN

In this article, a series of medical poly(ester-urethane)s (PEUs) with varying uniform-size hard segment content were prepared via one-step chain extension of poly(ε-caprolactone)s with aliphatic urethane diisocyanate, and the corresponding films were obtained by solvent evaporation technique. The chemical structures of polymers were confirmed by 1H NMR, FT-IR and GPC. The effect of uniform-size hard segment content on the physicochemical properties of PEU films, including thermal properties, mechanical properties, crystallization behavior, water-swelling behavior and in vitro degradability, was extensively researched. The PEU films exhibiting similar thermal transition and thermal stability indicated that the uniform-size hard segment content had little effect on the thermal properties. Two obvious glass transition temperatures observed in DSC curves manifested a microphase separation structure, which endowed the PEU films excellent mechanical properties with ultimate stress of 34.6-51.2 MPa and strain at break of 898-1485%. And with the increase of uniform-size hard segment content, the initial modulus and ultimate stress increased, while the strain at break decreased. Due to the compact physical-linking network structure formed by the denser hydrogen bonds, the PEU films exhibited low water-swellability of less than 1.5 wt% and low degradation rate in vitro. The weight loss of the PEU films in degradation test was less than 1 wt% at the first four months and the time of films becoming fragments was more than 15 months. Cytotoxicity test of film extracts was conducted with L929 mouse fibroblasts, and the relative growth rate approached or exceeded 75%, indicating an acceptable cytocompatibility. For the excellent mechanical properties, slow biodegradability, non-toxic degradation products and adequate cytocompatibility, the PEUs containing uniform-size hard segments possess a high potential to be applied as long-term implant biomaterials.


Asunto(s)
Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Metacrilatos/química , Poliésteres/química , Poliuretanos/química , Uretano/análogos & derivados , Espectroscopía de Resonancia Magnética , Ensayo de Materiales , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Uretano/química
14.
Polymers (Basel) ; 11(5)2019 May 11.
Artículo en Inglés | MEDLINE | ID: mdl-31083573

RESUMEN

To improve the hemocompatibility of the biodegradable medical poly(ether-ester-urethane) (PEEU), containing uniform-size aliphatic hard segments that was prepared in our lab, a copolymer containing phosphorylcholine (PC) groups was blended with the PEEU. The PC-copolymer of poly(MPC-co-EHMA) (PMEH) was first obtained by copolymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC) and 2-ethylhexyl methacrylate (EHMA), and then dissolved in mixed solvent of ethanol/chloroform to obtain a homogeneous solution. The composite films (PMPU) with varying PMEH content were prepared by solvent evaporation method. The physicochemical properties of the composite films with varying PMEH content were researched. The PMPU films exhibited higher thermal stability than that of the pure PEEU film. With the PMEH content increasing from 5 to 20 wt%, the PMPU films also possessed satisfied tensile properties with ultimate stress of 22.9-15.8 MPa and strain at break of 925-820%. The surface and bulk hydrophilicity of the films were improved after incorporation of PMEH. In vitro degradation studies indicated that the degradation rate increased with PMEH content, and it took 12-24 days for composite films to become fragments. The protein adsorption and platelet-rich plasma contact tests were adapted to evaluate the surface hemocompatibility of the composite films. It was found that the amount of adsorbed protein and adherent platelet on the surface decreased significantly, and almost no activated platelets were observed when PMEH content was above 5 wt%, which manifested good surface hemocompatibility. Due to the biodegradability, acceptable tensile properties and good surface hemocompatibility, the composites can be expected to be applied in blood-contacting implant materials.

15.
J Colloid Interface Sci ; 545: 172-183, 2019 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30878783

RESUMEN

Graphene oxide (GO), as a drug delivery carrier, has attracted considerable attention because of its interesting properties. However, GO tends to aggregate in aqueous solution. Amphiphilic molecules are usually necessary to stabilize GO. The introduction of these non-functional macromolecules on the one hand reduces drug loading, but on the other hand may cause unpredictable side effects. This study proposes a new strategy for stabilizing GO with a functional photothermal agent, IR820 (new indocyanine green) derivative. IR820 derivative results from the conjugation of active targeted lactobionic acid (LA) with IR820 for the formation of IR820-LA. IR820-LA features central aromatic groups that can associate with the GO basal plane through π-π interactions. The flanking moiety of hydrophilic LA and sulfonic groups thus provides steric stabilization of GO in aqueous solution. Moreover, IR820-LA endows GO/doxorubicin (GO/DOX) nanovehicles with fluorescence imaging ability and actively targeted chemo-photothermal therapy. Experimental results both in vitro and in vivo have indicated its good chemo-photothermal therapeutic effect according to its active tumor targeting ability and pH-sensitive drug release characteristics. Therefore, our GO/DOX/IR820-LA nanohybrids can be excellent nanoplatforms for active tumor-targeted chemo-photothermal therapy with imaging guidance.


Asunto(s)
Disacáridos/metabolismo , Doxorrubicina/farmacología , Portadores de Fármacos/química , Colorantes Fluorescentes/química , Grafito/química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Transporte Biológico , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Preparaciones de Acción Retardada/química , Doxorrubicina/química , Liberación de Fármacos , Humanos , Ratones , Terapia Molecular Dirigida/métodos , Imagen Óptica/métodos , Tamaño de la Partícula , Fototerapia/métodos , Propiedades de Superficie
16.
Langmuir ; 35(4): 894-900, 2019 01 29.
Artículo en Inglés | MEDLINE | ID: mdl-30607955

RESUMEN

In this work, interfacial reaction kinetics between α-[3-(2,3-epoxypropoxy)propyl]-ω-butyl-polydimethylsiloxane emulsion droplets with different sizes and gelatin was studied. The results of amino conversion rate determination show that the reaction proceeded in two steps. Fluorescence spectra analysis indicates that step 1 (0-2 h) should be the adsorption of gelatin on droplet surface. In step 2 (2-13 h), amino conversion rate increased rapidly. The reaction rate in step 2 ( k2) was obtained by using the 2nd-order approach to model the grafting reaction kinetics. The quantitative relationships among amino conversion rate, droplet size, the concentration of surfactant, reaction temperature, and time were described by linear regression models in given ranges of conditions in step 2. Thermodynamic analysis indicates that the interfacial reaction is an endothermic reaction. After 13 h, the reaction was almost stopped.

17.
Colloids Surf B Biointerfaces ; 171: 647-655, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-30107338

RESUMEN

Understanding the assembly mechanisms of supramolecular architectures in nature is essential for the design and synthesis of novel biomaterials. In the work, self-assembly of gelatin-mono epoxy terminated polydimethylsiloxane polymer (PGG) controlled by electrostatic and hydrophobic interactions between gelatin and sodium dodecyl sulfate (SDS) was investigated in suit. Confocal laser scanning microscopy, circular dichroism spectroscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy were conducted to reveal the structure evolution of PGG at a molecular level with the increment of SDS concentration, including micro-sized sphere, core-shell and multi-layer structure. Notably, the multi-layer structure was formed from the large contribution of antiparallel ß-sheets on the boundary and new hydrophobic aggregation driven by higher monomer conversions. The delicate supramolecular architectures preliminarily present excellent anti-water, anti-contamination and anti-radiation properties in the surface of skin. The excellent self-cleaning function of PGG indicates potential application in biomaterials.


Asunto(s)
Gelatina/química , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Tamaño de la Partícula , Dodecil Sulfato de Sodio/química , Electricidad Estática , Propiedades de Superficie
18.
J Biomater Appl ; 32(10): 1329-1342, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29547018

RESUMEN

The purpose of this study is to offer a novel kind of polyurethane with improved surface blood compatibility for long-term implant biomaterials. In this work, the aliphatic poly(ester-urethane) (PEU) with uniform-size hard segments was prepared and the PEU surface was grafted with hydrophilic poly(ethylene glycol) (PEG). The PEU was obtained by chain-extension of poly(ɛ-caprolactone) (PCL) with isocyanate-terminated urethane triblock. Free amino groups were introduced onto the surface of PEU film via aminolysis with hexamethylenediamine, and then the NH2-grafted PEU surfaces (PEU-NH2) were reacted with isocyanate-terminated monomethoxyl PEG (MPEG-NCO) to obtain the PEG-grafted PEU surfaces (PEU-PEG). Analysis by nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and gel permeation chromatography were performed to confirm the chemical structures of the chain extender, PCL, PEU, and PEU-PEG. Additionally, the influence of aminolysis on the physical-mechanical properties of PEU films was investigated. Two glass transition temperatures and a broad endothermic peak were observed in the differential scanning calorimetry curves of PEU, which demonstrated a microphase-separated and semicrystalline structure, respectively. The PEU-PEG film exhibited excellent mechanical properties with an ultimate stress of ∼39 MPa and an elongation at break of ∼1190%, which was slightly lower than that of PEU, indicating that the aminolysis has little influence on the tensile properties. Evaluation of the blood compatibility of the films by bovine serum albumin adsorption and the platelet adhesion test revealed that the PEG-grafted surface had improved resistance to protein adsorption and excellent resistance to platelet adhesion. In vitro degradation tests showed that the PEU-PEG film could maintain its mechanical properties for more than six months and only lost ∼25% weight after 18 months. Due to the excellent mechanical properties, good blood compatibility and slow degradability, this novel kind of polyurethane hold significant promise for long-term implant biomaterials, especially soft tissue augmentation and regeneration.


Asunto(s)
Materiales Biocompatibles/química , Isocianatos/química , Polietilenglicoles/química , Poliuretanos/química , Adsorción , Animales , Materiales Biocompatibles/síntesis química , Bovinos , Interacciones Hidrofóbicas e Hidrofílicas , Isocianatos/síntesis química , Ensayo de Materiales , Adhesividad Plaquetaria , Polietilenglicoles/síntesis química , Poliuretanos/síntesis química , Conejos , Albúmina Sérica Bovina/química , Propiedades de Superficie , Resistencia a la Tracción
19.
Polymers (Basel) ; 10(10)2018 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-30961050

RESUMEN

In the paper, poly(ethylene glycol) (PEG) was grafted on the surface of poly(ester-urethane) (SPEU) film with high grafting density for biomedical purposes. The PEG-surface-grafted SPEU (SPEU-PEG) was prepared by a three-step chemical treatment under mild-reaction conditions. Firstly, the SPEU film surface was treated with 1,6-hexanediisocyanate to introduce -NCO groups on the surface with high density (5.28 × 10-7 mol/cm²) by allophanate reaction; subsequently, the -NCO groups attached to SPEU surface were coupled with one of -NH2 groups of tris(2-aminoethyl)amine via condensation reaction to immobilize -NH2 on the surface; finally, PEG with different molecular weight was grafted on the SPEU surface through Michael addition between terminal C = C bond of monoallyloxy PEG and -NH2 group on the film surface. The chemical structure and modified surface were characterized by FT-IR, ¹H NMR, X-ray photoelectron spectroscopy (XPS), and water contact angle. The SPEU-PEGs displaying much lower water contact angles (23.9⁻21.8°) than SPEU (80.5°) indicated that the hydrophilic PEG chains improved the surface hydrophilicity significantly. The SPEU-PEG films possessed outstanding mechanical properties with strain at break of 866⁻884% and ultimate stress of 35.5⁻36.4 MPa, which were slightly lower than those of parent film, verifying that the chemical treatments had minimum deterioration on the mechanical properties of the substrate. The bovine serum albumin adsorption and platelet adhesion tests revealed that SPEU-PEGs had improved resistance to protein adsorption (3.02⁻2.78 µg/cm²) and possessed good resistance to platelet adhesion (781⁻697 per mm²), indicating good surface hemocompatibility. In addition, due to the high grafting density, the molecular weight of surface-grafted PEG had marginal effect on the surface hydrophilicity and hemocompatibility.

20.
Polymers (Basel) ; 10(6)2018 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-30966614

RESUMEN

The purpose of this study was to develop a process to achieve biodegradable chitooligosaccharide-based polyurethane (CPU) with improved hemocompatibility and mechanical properties. A series of CPUs with varying chitooligosaccharide (COS) content were prepared according to the conventional two-step method. First, the prepolymer was synthesized from poly(ε-caprolactone) (PCL) and uniform-size diurethane diisocyanates (HBH). Then, the prepolymer was chain-extended by COS in N,N-dimethylformamide (DMF) to obtain the weak-crosslinked CPU, and the corresponding films were obtained from the DMF solution by the solvent evaporation method. The uniform-size hard segments and slight crosslinking of CPU were beneficial for enhancing the mechanical properties, which were one of the essential requirements for long-term implant biomaterials. The chemical structure was characterized by FT-IR, and the influence of COS content in CPU on the physicochemical properties and hemocompatibility was extensively researched. The thermal stability studies indicated that the CPU films had lower initial decomposition temperature and higher maximum decomposition temperature than pure polyurethane (CPU-1.0) film. The ultimate stress, initial modulus, and surface hydrophilicity increased with the increment of COS content, while the strain at break and water absorption decreased, which was due to the increment of crosslinking density. The results of in vitro degradation signified that the degradation rate increased with the increasing content of COS in CPU, demonstrating that the degradation rate could be controlled by adjusting COS content. The surface hemocompatibility was examined by protein adsorption and platelet adhesion tests. It was found that the CPU films had improved resistance to protein adsorption and possessed good resistance to platelet adhesion. The slow degradation rate and good hemocompatibility of the CPUs showed great potential in blood-contacting devices. In addition, many active amino and hydroxyl groups contained in the structure of CPU could carry out further modification, which made it an excellent candidate for wide application in biomedical field.

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