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1.
Life Sci ; 270: 119126, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33508295

RESUMEN

AIMS: To investigate the biomimetic fabrication of fibrous-like organic-inorganic hybrid structures via a simple bottom-up approach, viz. self-assembly of simple molecules, and apply fibrous-like composites as a novel primer to improve dentin bond strengths of self-etch adhesives. MATERIALS AND METHODS: The resultants of commercial amorphous calcium phosphate (ACP) nanoparticles and 10-methacryloyloxydecyl dihydrogen phosphate (MDP) ethanol-aqueous solution were analyzed by TEM, SEM, XRD, DLS and AFM. The acid and alkali resistance of abovementioned self-assembled composites were analyzed with TEM. Micro-tensile bond strengths (MTBS) tests were performed after polished dentin surfaces were pretreated with self-assembled composites. The pretreated dentin surfaces and dentin-resin interfaces were characterized by SEM/TEM. KEY FINDINGS: ACP nanoparticles in MDP solution could self-assemble into fibrous-like nanotube structures in 8 nm diameter. Self-assembly and self-proliferation process went from ACP nanoparticles, dissolved ACP nanoparticles (less than 50 nm), twig-like structures and fibrous-like nanotubes to cellular networks. The fibrous-like nanotubes were only detected when the amount of ACP in reaction system were more than 0.01 g. The more ACP interacted with MDP, the more fibrous-like nanotubes were formed. After the dentin surfaces were treated with fibrous-like nanotube composites, MTBS could be significantly improved. Moreover, the fibrous-like nanotube structures could be resistant to acidic challenge, and were stable at least for 3 months. SIGNIFICANCE: The fibrous-like nanotube structures could be self-assembled via a bottom-up approach at certain ratio of MDP and commercial ACP nanoparticles. The application of fibrous-like nanotube composites as a novel primer prior to self-etch adhesives greatly improved dentin bond strengths.


Asunto(s)
Biomimética/métodos , Dentina/química , Nanotubos/química , Adhesivos/química , Fosfatos de Calcio/química , Humanos , Ensayo de Materiales/métodos , Metacrilatos/química , Nanopartículas/química , Resistencia a la Tracción/fisiología
2.
Int J Mol Sci ; 22(2)2021 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-33445775

RESUMEN

Accelerating wound healing with minimized bacterial infection has become a topic of interest in the development of the new generation of tissue bio-adhesives. In this study, we fabricated a hydrogel system (MGC-g-CD-ic-TCS) consisting of triclosan (TCS)-complexed beta-cyclodextrin (ß-CD)-conjugated methacrylated glycol chitosan (MGC) as an antibacterial tissue adhesive. Proton nuclear magnetic resonance (1H NMR) and differential scanning calorimetry (DSC) results showed the inclusion complex formation between MGC-g-CD and TCS. The increase of storage modulus (G') of MGC-g-CD-ic-TCS after visible light irradiation for 200 s indicated its hydrogelation. The swollen hydrogel in aqueous solution resulted in two release behaviors of an initial burst and sustained release. Importantly, in vitro and in vivo results indicated that MGC-g-CD-ic-TCS inhibited bacterial infection and improved wound healing, suggesting its high potential application as an antibacterial tissue bio-adhesive.


Asunto(s)
Adhesivos/química , Quitosano/química , Glicoles/química , Hidrogeles/química , Triclosán/química , beta-Ciclodextrinas/química , Animales , Antibacterianos/química , Antibacterianos/farmacología , Luz , Masculino , Ratones , Ratas , Ratas Sprague-Dawley , Cicatrización de Heridas/efectos de los fármacos
3.
Methods Mol Biol ; 2211: 183-191, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33336278

RESUMEN

The simple and versatile CRISPR/Cas9 system is a promising strategy for genome editing in mammalian cells. Generally, the genome editing components, namely Cas9 protein and single-guide RNA (sgRNA), are delivered in the format of plasmids, mRNA, or ribonucleoprotein (RNP) complexes. In particular, non-viral approaches are desirable as they overcome the safety concerns posed by viral vectors. To control cell fate for tissue regeneration, scaffold-based delivery of genome editing components will offer a route for local delivery and provide possible synergistic effects with other factors such as topographical cues that are co-delivered by the same scaffold. In this chapter, we detail a simple method of surface modification to functionalize electrospun nanofibers with CRISPR/Cas9 RNP complexes. The mussel-inspired bio-adhesive coating will be used as it is a simple and effective method to immobilize biomolecules on the surface. Nanofibers will provide a biomimicking microenvironment and topographical cues to seeded cells. For evaluation, a model cell line with single copies of enhanced green fluorescent protein (U2OS.EGFP) will be used to validate the efficiency of gene disruption.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Ribonucleoproteínas/metabolismo , Andamios del Tejido , Adhesivos/química , Animales , Proteína 9 Asociada a CRISPR/química , Línea Celular , Expresión Génica , Técnicas de Transferencia de Gen , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Lípidos/química , Sustancias Macromoleculares/química , Sustancias Macromoleculares/metabolismo , Nanofibras/química , ARN Guia/química , ARN Guia/genética , Ribonucleoproteínas/genética , Ingeniería de Tejidos , Andamios del Tejido/química
4.
J Mater Chem B ; 9(3): 783-792, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33333547

RESUMEN

Pesticides play a very important role in pest control and plant protection. However, they can be limited by a tendency to cause ecological system damage due to significant losses into the environment. To increase pesticide utilization efficiency, we developed highly leaf-adhesive avermectin nanocapsules (Av-pH-cat@CS) with pH-responsive controlled release properties. The Av-pH-cat@CS nanocapsules displayed good thermal stability and photostability in response to UV light irradiation. The Av-pH-cat@CS nanocapsules could be disrupted at low pH and they exhibited excellent controlled release in response to pH, which improved the release of avermectins. In addition, the Av-pH-cat@CS nanocapsules were highly adhesive to crop leaves as a result of strong hydrogen bonding, which prolonged the retention time on crop leaves. The Av-pH-cat@CS nanocapsules with pH-responsive release and strong leaf adhesion improved the control efficacy and enhanced the utilization efficiency. Our findings offer a promising approach to prolonging pesticide duration on crop leaves and improving the utilization efficiency.


Asunto(s)
Adhesivos/química , Antiprotozoarios/química , Ivermectina/análogos & derivados , Nanocápsulas/química , Plaguicidas/química , Adhesivos/síntesis química , Antiprotozoarios/síntesis química , Liberación de Fármacos , Enlace de Hidrógeno , Concentración de Iones de Hidrógeno , Ivermectina/síntesis química , Ivermectina/química , Estructura Molecular , Tamaño de la Partícula , Plaguicidas/síntesis química , Hojas de la Planta/química , Propiedades de Superficie , Factores de Tiempo , Zea mays/química
5.
Carbohydr Polym ; 251: 117019, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33142580

RESUMEN

The advent of high-performance conductive organohydrogels, which are sustainable in extremely cold environment, has attracted immersing interest in biosensors. In this work, a highly stretchable, self-healable, adhesive and antibacterial cellulose-based ionic conductive organohydrogel with low-temperature strain sensitivity was developed, using in-situ polymerization of acrylamide in glycerol-water with poly (vinyl alcohol), chitosan, FeCl3 and 2,2,6,6-Tetramethylpiperidine-1-oxyl oxidized cellulose nanofibril (TCNF). Owing to their chemically cross-linked structures and multiple H-bonding networks, the organohydrogel exhibits excellent mechanical properties, such as high stretchability (540 %), high compression strength (0.44 MPa), nearly 87 % self-healing efficiency and adhesive to various substrates. Also, good antibacterial property was confirmed by the diameter of inhibition zone (∼5.1 mm) against Salmonella enteritidis. Notably, the organohydrogels remained high conductivity and flexibility even below -20 °C, which can be applied as low-temperature strain sensor for real-time. Therefore, it has promising applications in artificial intelligence and personal healthcare under cold environment.


Asunto(s)
Acrilamida/química , Antibacterianos/química , Técnicas Biosensibles , Celulosa/química , Quitosano/química , Hidrogeles , Adhesivos/química , Antibacterianos/farmacología , Frío , Conductividad Eléctrica , Hidrogeles/síntesis química , Hidrogeles/química , Fenómenos Mecánicos , Salmonella enteritidis/efectos de los fármacos
6.
Carbohydr Polym ; 254: 117478, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33357930

RESUMEN

Waterborne polyurethanes (WBPUs) have been proposed as ecofriendly elastomers with several applications in coatings and adhesives. WBPU's physicochemical properties can be enhanced by the addition of cellulose nanocrystals (CNCs). The way CNCs are isolated has a strong effect on their properties and can determine their role as reinforcement. In this work, CNCs produced using ancestral endoglucanase (EnCNCs) were used as reinforcement for WBPU and compared with CNC produced by sulfuric acid hydrolysis (AcCNC). The enzymatic method produced highly thermostable and crystalline CNCs. The addition of small contents of EnCNCs improved the thermomechanical stability and mechanical properties of WBPUs, even better than commercial AcCNCs. Besides, WBPU reinforced by adding EnCNCs was studied as a coating for paper materials, increasing its abrasion resistance and as electrospun nanocomposite mats where EnCNCs helped maintaining the morphology of the fibers.


Asunto(s)
Celulasa/química , Celulosa/química , Tecnología Química Verde , Nanopartículas/química , Poliuretanos/química , Adhesivos/química , Celulasa/genética , Celulasa/metabolismo , Materiales de Construcción/análisis , Humanos , Hidrólisis , Nanocompuestos/química , Nanocompuestos/ultraestructura , Nanopartículas/ultraestructura , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ácidos Sulfúricos/química , Agua/química
7.
Acta Odontol Latinoam ; 33(2): 135-142, 2020 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-32920616

RESUMEN

This study evaluated the influence of the mode and time of solvent evaporation on the tensile strength (TS), flexural strength (FS) and elastic modulus (EM) of two adhesive systems: Scotchbond Multipurpose (SBMP) and Clearfil SE (CSEB). For this purpose, rectangular samples (2x1x7 mm) were prepared with 10 µL of primer and the solvents were evaporated with air spray at (23±1) ºC, (40±1) ºC and negative control (without spray). For each temperature, the times of 5, 20, 30, and 60 seconds were investigated. The statistical results showed that evaporation at 40±1ºC resulted in better EM for the two adhesives tested and all the evaporation times evaluated. However, there were no significant differences between the times and modes of evaporation for TS. The results of this study indicate that evaporation at a temperature of (40±1) °C could improve the elastic modulus of both adhesives tested, regardless of the evaporating time.


Asunto(s)
Adhesivos/química , Cementos Dentales/química , Recubrimientos Dentinarios/química , Solventes/farmacología , Resistencia a la Tracción , Desecación , Humanos , Ensayo de Materiales , Volatilización
8.
Niger J Clin Pract ; 23(8): 1148-1154, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32788494

RESUMEN

Aims: The effect of mechanical loading on the microtensile bond strength (µTBS) of universal adhesives to dentin was evaluated in this study. Methods and Materials: Human molar teeth had the occlusal dentin surfaces exposed and were allocated into ten groups (five experimental groups and five control groups) that used the following universal adhesive systems in self-etch mode: All-Bond Universal (ABU), Single Bond Universal (SBU), Gluma Bond Universal (GBU), Tetric N-Bond Universal (TBU), and Clearfil Universal Bond (CUB). Following the bonding procedures and build-ups, the specimens were either stored in water at 37°C for 24 h or were mechanically loaded (50 N for 60,000 cycles) prior to the µTBS test. Data were analyzed using the one-way analysis of variance (ANOVA) and Tukey's posthoc test (P = 0.05). Results: Both the adhesive type and mechanical loading had significant effects on the µTBS (P < 0.05). The µTBS values of SBU and ABU were significantly higher than the values of the other adhesives (P < 0.05). However, the µTBS values of ABU decreased significantly after mechanical loading (P < 0.05). Conclusions: With the exception of ABU, mechanical loading had no deleterious effects on the µTBS of the universal adhesive systems examined in this study.


Asunto(s)
Adhesivos/química , Recubrimiento Dental Adhesivo/métodos , Recubrimientos Dentinarios/química , Bisfenol A Glicidil Metacrilato , Resinas Compuestas , Glutaral , Humanos , Ensayo de Materiales/métodos , Diente Molar , Ácidos Polimetacrílicos , Cementos de Resina/química , Resistencia a la Tracción
9.
Nat Commun ; 11(1): 3895, 2020 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-32753588

RESUMEN

The mussel byssus has long been a source of inspiration for the adhesion community. Recently, adhesive synergy between flanking lysine (Lys, K) and 3,4-Dihydroxyphenylalanine (DOPA, Y) residues in the mussel foot proteins (Mfps) has been highlighted. However, the complex topological relationship of DOPA and Lys as well as the interfacial adhesive roles of other amino acids have been understudied. Herein, we study adhesion of Lys and DOPA-containing peptides to organic and inorganic substrates using single-molecule force spectroscopy (SMFS). We show that a modest increase in peptide length, from KY to (KY)3, increases adhesion strength to TiO2. Surprisingly, further increase in peptide length offers no additional benefit. Additionally, comparison of adhesion of dipeptides containing Lys and either DOPA (KY) or phenylalanine (KF) shows that DOPA is stronger and more versatile. We furthermore demonstrate that incorporating a nonadhesive spacer between (KY) repeats can mimic the hidden length in the Mfp and act as an effective strategy to dissipate energy.


Asunto(s)
Adhesivos/química , Dihidroxifenilalanina/química , Lisina/química , Secuencia de Aminoácidos , Animales , Bivalvos , Dipéptidos , Péptidos/síntesis química , Propiedades de Superficie , Titanio/química
10.
J Vis Exp ; (161)2020 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-32716389

RESUMEN

The analysis of thermal processes associated to the curing of adhesives and the study of mechanical behavior once cured, provide key information to choose the best option for any specific application. The proposed methodology for the curing characterization, based on thermal analysis and rheology, is described through the comparison of three commercial adhesives. The experimental techniques used here are Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC) and Rheology. TGA provides information about the thermal stability and filler content, DSC allows the evaluation of some thermal events associated to the cure reaction and to thermal changes of the cured material when subjected to temperature changes. Rheology complements the information of the thermal transformations from a mechanical point of view. Thus, the curing reaction can be tracked through the elastic modulus (mainly the storage modulus), the phase angle and the gap. In addition, it is also shown that although DSC is of no use to study the curing of moisture curable adhesives, it is a very convenient method to evaluate the low temperature glass transition of amorphous systems.


Asunto(s)
Adhesivos/química , Rastreo Diferencial de Calorimetría , Módulo de Elasticidad , Ensayo de Materiales , Reología , Termogravimetría
11.
Proc Natl Acad Sci U S A ; 117(28): 16127-16137, 2020 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-32601214

RESUMEN

Thrombogenic reaction, aggressive smooth muscle cell (SMC) proliferation, and sluggish endothelial cell (EC) migration onto bioinert metal vascular stents make poststenting reendothelialization a dilemma. Here, we report an easy to perform, biomimetic surface engineering strategy for multiple functionalization of metal vascular stents. We first design and graft a clickable mussel-inspired peptide onto the stent surface via mussel-inspired adhesion. Then, two vasoactive moieties [i.e., the nitric-oxide (NO)-generating organoselenium (SeCA) and the endothelial progenitor cell (EPC)-targeting peptide (TPS)] are clicked onto the grafted surfaces via bioorthogonal conjugation. We optimize the blood and vascular cell compatibilities of the grafted surfaces through changing the SeCA/TPS feeding ratios. At the optimal ratio of 2:2, the surface-engineered stents demonstrate superior inhibition of thrombosis and SMC migration and proliferation, promotion of EPC recruitment, adhesion, and proliferation, as well as prevention of in-stent restenosis (ISR). Overall, our biomimetic surface engineering strategy represents a promising solution to address clinical complications of cardiovascular stents and other blood-contacting metal materials.


Asunto(s)
Adhesivos/química , Materiales Biocompatibles Revestidos/química , Péptidos/química , Stents , Adhesivos/síntesis química , Animales , Materiales Biomiméticos/síntesis química , Materiales Biomiméticos/química , Adhesión Celular , Movimiento Celular , Proliferación Celular , Células Cultivadas , Química Clic , Células Progenitoras Endoteliales/citología , Endotelio Vascular/citología , Endotelio Vascular/fisiología , Humanos , Miocitos del Músculo Liso/citología , Óxido Nítrico/química , Compuestos de Organoselenio/química , Péptidos/síntesis química , Proteínas/química , Conejos , Stents/efectos adversos , Trombosis/etiología , Trombosis/prevención & control
12.
J Vis Exp ; (159)2020 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-32478730

RESUMEN

The properties of cured wood adhesives are difficult to study because of the loss of water and other components to the wood, the influence of wood on the adhesive cure, and the effect of adhesive penetration on the wood interphase; thus, normal testing of a neat adhesive film is generally not useful. Most tests of wood adhesive bond strength are slow, laborious, can be strongly influenced by the wood and do not provide information on the kinetics of cure. Test method ASTM D 7998-19, however, can be used for fast evaluation of the strength of wood bonds. The use of a smooth, uniform, and strong wood surface, like maple face-veneer, and sufficient bonding pressure reduces the adhesion and wood strength effects on bond strength. This method has three main applications. The first is to provide consistent data on bond strength development. The second is to measure the dry and wet strengths of bonded lap shear samples. The third is to better understand the adhesive heat resistance by quickly evaluating thermal sensitivity and distinguishing between thermal softening and thermal degradation.


Asunto(s)
Adhesivos/química , Ensayo de Materiales/métodos , Madera/química , Resistencia al Corte
13.
AAPS PharmSciTech ; 21(4): 120, 2020 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-32323091

RESUMEN

The objective of this study was to develop a simpler and more practical quantitative evaluation method of cold flow (CF) in transdermal drug delivery systems (TDDSs). CF was forcibly induced by loading a weight on a punched-out sample (bisoprolol and tulobuterol tapes). When the extent of CF was analyzed using the area of oozed adhesive as following a previously reported method, the CF profiles were looked different between the samples 12 mm in diameter subjected to a 0.5-kg weight and samples 24 mm in diameter subjected to a 2.0-kg weight despite an equal load per unit area (4.42 g/mm2). The width of oozed adhesive around the original sample was suggested to be an index that properly describes the relationship between the load per unit area and the extent of CF. Further, it was clarified that the average CF width over the entire circumference of the sample was the same whether the samples were round or square as long as the sample area and load were the same. We also observed a linear relationship between the CF width and the aspect ratio of oval and rectangular samples. These results indicated that the CF properties of typical TDDS products lacking CF-proof processing at the edges could be determined by testing samples cut from the product rather than the whole TDDS patch. The proposed width measuring method was simple and useful for optimizing the composition of the adhesive and for testing the quality of the product.


Asunto(s)
Adhesivos/farmacocinética , Frío , Sistemas de Liberación de Medicamentos/métodos , Terbutalina/análogos & derivados , Adhesivos/administración & dosificación , Adhesivos/química , Administración Cutánea , Agonistas Adrenérgicos beta/administración & dosificación , Agonistas Adrenérgicos beta/química , Agonistas Adrenérgicos beta/farmacocinética , Evaluación Preclínica de Medicamentos/métodos , Terbutalina/administración & dosificación , Terbutalina/química , Terbutalina/farmacocinética
14.
Biofouling ; 36(3): 245-255, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32326753

RESUMEN

Dental plaque is a biofilm composed of a complex oral microbial community. The accumulation of plaque in the pit and fissures of dental elements often leads to the development of tooth decay (dental caries). Here, potent anti-biofilm materials were developed by incorporating zinc methacrylates or di-n-butyl-dimethacrylate-tin into the light-curable sealant and their physical, mechanical, and biological properties were evaluated. The data revealed that 5% di-n-butyl-dimethacrylate-tin (SnM 5%) incorporated sealant showed strong anti-biofilm efficacy against various single-species (Streptococcus mutans or Streptococcus oralis or Candida albicans) and S. mutans-C. albicans cross-kingdom dual-species biofilms without either impairing the mechanical properties of the sealant or causing cytotoxicities against mouse fibroblasts. The findings indicate that the incorporation of SnM 5% in the experimental pit and fissure self-adhesive sealant may have the potential to be part of current chemotherapeutic strategies to prevent the formation of cariogenic oral biofilms that cause dental caries.


Asunto(s)
Adhesivos/farmacología , Biopelículas/efectos de los fármacos , Caries Dental/prevención & control , Selladores de Fosas y Fisuras/farmacología , Zinc/química , Adhesivos/química , Animales , Biopelículas/crecimiento & desarrollo , Candida albicans/efectos de los fármacos , Candida albicans/crecimiento & desarrollo , Caries Dental/microbiología , Humanos , Metacrilatos/química , Ratones , Microbiota/efectos de los fármacos , Selladores de Fosas y Fisuras/química , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/crecimiento & desarrollo , Streptococcus oralis/efectos de los fármacos , Streptococcus oralis/crecimiento & desarrollo
15.
Molecules ; 25(4)2020 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-32075064

RESUMEN

Freestanding films based on catechol functionalized chitosan (CHI), hyaluronic acid (HA), and bioglass nanoparticles (BGNPs) were developed by spin-coating layer-by-layer assembly (SA-LbL). The catechol groups of 3,4-dihydroxy-l-phenylalanine (DOPA) present in the marine mussels adhesive proteins (MAPs) are the main factors responsible for their characteristic strong wet adhesion. Then, the produced films were cross-linked with genipin to improve their stability in wet state. Overall, the incorporation of BGNPs resulted in thicker and bioactive films, hydrophilic and rougher surfaces, reduced swelling, higher weight loss, and lower stiffness. The incorporation of catechol groups onto the films showed a significant increase in the films' adhesion and stiffness, lower swelling, and weight loss. Interestingly, a synergetic effect on the stiffness increase was observed upon the combined incorporation of BGNPs with catechol-modified polymers, given that such films were the stiffest. Regarding the biological assays, the films exhibited no negative effects on cellular viability, adhesion, and proliferation, and the BGNPs seemed to promote higher cellular metabolic activity. These bioactive LbL freestanding films combine enhanced adhesion with improved mechanical properties and could find applications in the biomedical field, such as guided hard tissue regeneration membranes.


Asunto(s)
Materiales Biomiméticos/química , Materiales Biocompatibles Revestidos/química , Nanopartículas/química , Polisacáridos/farmacología , Adhesivos/química , Adhesivos/farmacología , Catecoles/química , Adhesión Celular/efectos de los fármacos , Cerámica/química , Quitosano/química , Materiales Biocompatibles Revestidos/farmacología , Ácido Hialurónico/química , Ensayo de Materiales , Membranas Artificiales , Polímeros/química , Polisacáridos/química , Proteínas/química
16.
Int J Pharm ; 578: 119132, 2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-32057892

RESUMEN

This study investigated the effects of drug recrystallization on the in vitro performance of testosterone drug-in-adhesive transdermal delivery system (TDS). Six formulations were prepared with a range of dry drug loading in the adhesive matrix from 1% to 10% w/w with the aim of generating TDS with various levels of drug crystals. We visually quantified the amount of crystals in TDS by polarized light microscopy. The effect of drug recrystallization on adhesion, tackiness, cohesive strength, viscoelasticity, drug release, and drug permeation through human cadaver skin were evaluated for these TDS samples. The Optical images showed no crystals in 1% and 2% testosterone TDSs; however, the amount of crystals increased by increasing testosterone loading from 4 to 10%. A proportional and significant decrease (p < 0.05) in tack, peel, and shear strength of the adhesive matrix with increasing amount of crystals in TDS was observed. The drug crystals resulted in a proportional deterioration of the viscoelastic properties of the adhesive matrix. The 2% testosterone TDS showed faster drug release rate when compared to 1% testosterone TDS. The increase in drug loading from 2% to 4% w/w slightly increased the cumulative amount of testosterone released. Further increase in drug loading in TDS to 6, 8, and 10% was nonsignificant (p > 0.05) to affect the drug release and permeation. In conclusion, this study demonstrated that the extent of drug recrystallization can be quantitatively correlated with the deterioration of performance characteristics of TDS products.


Asunto(s)
Adhesivos/química , Preparaciones Farmacéuticas/administración & dosificación , Preparaciones Farmacéuticas/química , Piel/efectos de los fármacos , Testosterona/administración & dosificación , Testosterona/química , Administración Cutánea , Anciano , Cristalización/métodos , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos/efectos de los fármacos , Humanos , Persona de Mediana Edad , Permeabilidad/efectos de los fármacos , Reología/métodos , Absorción Cutánea/efectos de los fármacos , Parche Transdérmico
17.
Carbohydr Polym ; 234: 115898, 2020 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-32070518

RESUMEN

A hybrid poly(N-isopropylacrylamide) (PNIPAm)/cellulose nanofibrils (CNFs) hydrogel composite was fabricated by inverted stereolithography 3D printing to provide a new platform for regulating lower critical solution temperature (LCST) properties and thus tuning optical and bioadhesive properties. The phenomena of interest in the as-printed PNIPAm/CNF hydrogels may be attributed to the fiber-reinforced composite system between crosslinked PNIPAm and CNFs. The optical tunability was found to be correlated to the micro/nano structures of the PNIPAm/CNF hydrogel films. It was found that PNIPAm/CNF hydrogels exhibit switchable bioadhesivity to bacteria in response to CNF distribution in the hydrogels. After 2.0 wt% CNF was incorporated, it was found that a remarkable 8°C reduction of the LCST was achieved relative to PNIPAm hydrogel crosslinked by TEGDMA without CNF. The prepared PNIPAm/CNF hydrogels possessed highly reversible optical, bioadhesion, and thermal performance, making them suitable to be used as durable temperature-sensitive sensors and functional biomedical devices.


Asunto(s)
Resinas Acrílicas/química , Adhesivos/química , Celulosa/química , Hidrogeles/química , Nanofibras/química , Impresión Tridimensional , Óptica y Fotónica , Tamaño de la Partícula , Propiedades de Superficie
18.
Int J Pharm ; 578: 119081, 2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-32006623

RESUMEN

Osteoarthritis is a major problem in elder people. Etoricoxib-loaded bio-adhesive hybridized nanoparticles were prepared using polylactic acid (PLA) and chitosan hydrochloride (CS-HCl) in presence of Captex®200 as a liquid oil, polyvinyl alcohol (PVA) and Tween®80 as surfactants. The study aimed to present a new intra-articular treatment of osteoarthritis with anti-inflammatory as well as bone rebuilding effects. Hybridized nanoparticles were fabricated applying the emulsion solvent evaporation technique then assessed for particle size, zeta potential, entrapment efficiency and in-vitro drug release. Furthermore, FT-IR and DSC in addition to morphological examination were done. Results revealed that the formulation composed of PLA:Captex®200 in ratio 1:2 (w/w), 1%w/v Tween®80, 0.3% w/v CS-HCl and 3%w/v PVA possessed the smallest particle size and the most sustained drug release, thus was sorted for further analyses. The selected formulation ability to interact with the negatively charged sodium fluroscein was evaluated to predict its binding with the naturally occurring hyaluronic acid in the knee joint where promising results were obtained. Results showed the cytocompatibility of the formulation when tested using MC3T3-E1 normal bone cell line, enhanced ALP activity and increased calcium ion deposition and binding. Results suggested that the presented formulation can be considered as an innovative approach for osteoarthritis.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Quitosano/administración & dosificación , Etoricoxib/administración & dosificación , Nanopartículas/administración & dosificación , Poliésteres/administración & dosificación , Adhesivos/administración & dosificación , Adhesivos/química , Fosfatasa Alcalina/metabolismo , Antiinflamatorios no Esteroideos/química , Calcio/metabolismo , Línea Celular , Supervivencia Celular/efectos de los fármacos , Quitosano/química , Liberación de Fármacos , Etoricoxib/química , Humanos , Inyecciones Intraarticulares , Nanopartículas/química , Osteoartritis/tratamiento farmacológico , Poliésteres/química , Polisorbatos/administración & dosificación , Polisorbatos/química
19.
Sci Rep ; 10(1): 2612, 2020 02 13.
Artículo en Inglés | MEDLINE | ID: mdl-32054875

RESUMEN

Underwater adhesion in mussels (Bivalvia) is an extreme adaptation to achieve robust and firm wet adhesion in the freshwater/brackish/ocean, which biochemically shaped through millions of years. The protein-based adhesion has huge prospective in various fields like industry, medical, etc. Currently, no comprehensive records related to the systematic documentation of structural and functional properties of Mussel foot proteins (Mfps). In this study, we identified the nine species of bivalves in which the complete sequence of at least one adhesive protein is known. The insilico characterization revealed the specific physio-chemical structural and functional characters of each Mfps. The evolutionary analyses of selected bivalves are mainly based on Mfps, Mitogenome, and TimeTree. The outcome of the works has great applications for designing biomimetic materials in future.


Asunto(s)
Bivalvos/química , Bivalvos/genética , Proteínas/química , Proteínas/genética , Adhesivos/química , Adhesivos/metabolismo , Secuencia de Aminoácidos , Animales , Bivalvos/metabolismo , Evolución Molecular , Genoma Mitocondrial , Iones/metabolismo , Modelos Moleculares , Filogenia , Conformación Proteica , Proteínas/metabolismo
20.
Nanoscale ; 12(3): 1307-1324, 2020 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-31907498

RESUMEN

The rapid and robust adhesion of marine mussels to diverse solid surfaces in wet environments is mediated by the secreted mussel adhesive proteins which are abundant in a catecholic amino acid, l-3,4-dihydroxyphenylalanine (Dopa). Over the last two decades, enormous efforts have been devoted to the development of synthetic mussel-inspired adhesives with water-resistant adhesion and cohesion properties by modifying polymer systems with Dopa and its analogues. In the present review, an overview of the unique features of various mussel foot proteins is provided in combination with an up-to-date understanding of catechol chemistry, which contributes to the strong interfacial binding via balancing a variety of covalent and noncovalent interactions including oxidative cross-linking, electrostatic interaction, metal-catechol coordination, hydrogen bonding, hydrophobic interactions and π-π/cation-π interactions. The recent developments of novel Dopa-containing adhesives with on-demand mechanical properties and other functionalities are then summarized under four broad categories: viscous coacervated adhesives, soft adhesive hydrogels, smart adhesives, and stiff adhesive polyesters, where their emerging applications in engineering, biological and biomedical fields are discussed. Limitations of the developed adhesives are identified and future research perspectives in this field are proposed.


Asunto(s)
Adhesivos/química , Materiales Biomiméticos/química , Bivalvos/química , Hidrogeles/química , Proteínas/química , Animales
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