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1.
Methods Mol Biol ; 2720: 101-113, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37775660

RESUMO

Recombinant elastin-based proteins (ELPs) are used in applications that include therapeutics, drug delivery, and tissue engineering due to their biocompatibility and unique ability to undergo simple coacervation. Here, we describe a cost-effective method to purify ELPs utilizing salt precipitation and their reversible phase transition property when heated above their lower critical solution temperature (LCST). Furthermore, we describe the post-translational modification of converting tyrosine residues to L-3,4-dihydroxyphenylalanine (DOPA) for adhesive applications.


Assuntos
Sistemas de Liberação de Medicamentos , Elastina , Elastina/química , Proteínas Recombinantes/genética , Transição de Fase , Adesivos
2.
An Acad Bras Cienc ; 95(3): e20220856, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37909564

RESUMO

The properties of adhesive mortars can change due to heating, compromising the durability of the coating systems. The aim of this article was to evaluate the influence of cement and polymer contents on the tensile bond strength of adhesive mortars after thermal storage. Ceramic tiling system specimens were prepared with seventeen formulations of adhesive mortars. These specimens were stored under dry (reference) at temperature of 23 ± 2 °C and 60 ± 5% of relative humidity and thermal (temperature of 70 ± 2 °C) conditions. The results showed that the cement content was the major factor concerning tensile bond strength. The vinyl acetate-ethylene (VAE) polymer improved the tensile bond strength of mortars under thermal storage. However, the hydroxypropyl methyl cellulose (HPMC) content contributed to the tensile bond strength only when higher cement contents were used. Besides, microstructure analysis showed that ettringite was degraded during thermal storage.


Assuntos
Adesivos , Polietilenos , Cimentos de Resina/química , Resistência à Tração , Polímeros , Metilcelulose , Propriedades de Superfície
3.
J Appl Oral Sci ; 31: e20230224, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37909528

RESUMO

OBJECTIVE: This study aimed to evaluate whether the use of desensitizing dentifrices containing obliterating agents can affect bond strength of eroded/abraded dentin. METHODOLOGY: A total of 100 dentin samples were obtained from human molars. The teeth were cut into 3 mm-thickness discs and allocated in five groups (n=20), according to the toothpaste used: WoF - abrasion with fluoride-free toothpaste (Cocoricó); Arg - toothpaste containing arginine (Colgate Sensitive Pro-Relief); Nov - calcium sodium phosphosilicate toothpaste (Sensodyne Repair and Protect); SnF - fluoride-containing toothpaste (AmF/SnCl2/SnF2 - Elmex Erosion); and Control (no erosive/abrasive process). The erosive/abrasive cycle consisted of immersion in citric acid (1%, pH 2.6, 5 min, 4×/day) and abrasion (2×/day, 120-20 sec abrasion, 100 sec immersion) with each toothpaste. During intervals, samples were immersed in artificial saliva. This cycle was performed for five days. Two resin cylinders (2 mm in diameter) were constructed on each sample for the shear bond strength test using a universal adhesive system. The self-etch and etch-and-rinse (Scotchbond Universal) strategies were employed, each in half of the total sample (n=10). Bond strength (MPa) was measured in a shear test and failure modes were assessed with a stereomicroscope. Statistical analysis was performed using the two-way analysis of variance (ANOVA) and Tukey tests (p<0.05). RESULTS: A statistically significant difference was found between the adhesive strategies tested (p<0.001), with the self-etching form showing higher values than the etch-and-rinse. Moreover, no significant differences were observed between the tested toothpastes (p=0.750) and interactions (p=0.438). CONCLUSION: The use of toothpaste containing obliterating agents does not affect bond strength to dentin subjected to erosive/abrasive conditions when a universal adhesive is used. However, the self-etch strategy might be preferred for eroded/abraded dentin.


Assuntos
Colagem Dentária , Dentifrícios , Humanos , Cimentos Dentários/farmacologia , Dentifrícios/farmacologia , Dentina , Cremes Dentais/farmacologia , Cimentos de Resina/química , Fluoreto de Sódio/farmacologia , Adesivos Dentinários , Teste de Materiais , Adesivos/farmacologia
4.
Eur Rev Med Pharmacol Sci ; 27(20): 9628-9638, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37916328

RESUMO

OBJECTIVE: This study aimed to investigate the effect of adhesive thinning on resin-dentin-bonded interfaces created by two simplified adhesives. MATERIALS AND METHODS: Micro-tensile bond strengths and interfacial nanoleakage were evaluated within bonded dentin interfaces formed by Adper Single Bond 2 and Single Bond Universal after 24 hours and 6 months of water storage. The adhesives were subjected to three different techniques: air-thinning, brush-thinning, or application without thinning. Statistical analysis was performed using a multi-level analysis of variance followed by Bonferroni's post-hoc test, at a significance level of 0.05. RESULTS: Adper Single Bond 2 demonstrated the highest immediate microtensile bond strengths (43.5 ± 1.3 MPa) and the lowest immediate nanoleakage (49.8 ± 2.8%) when air-thinning was employed. Single Bond Universal exhibited the lowest nanoleakage (36.4 ± 1.8%) when air-thinning was used, although there was no significant difference in immediate bond strengths between air-thinning and brush-thinning approaches, which both showed higher values compared to the no-thinning approach. After 6 months of storage, a significant decrease in bond strengths and a significant increase in nanoleakage were observed across most groups (p < 0.001). CONCLUSIONS: While all groups displayed varying degrees of instability over a 6-month storage period, air-thinning of simplified etch-and-rinse and self-etch adhesives proved to provide clinically acceptable bonded interfaces. The findings suggest that adhesive thinning techniques can play a vital role in enhancing bond stability and longevity in resin-dentin-bonded interfaces.


Assuntos
Dentina , Cimentos de Resina , Adesivos , Adesivos Dentinários/química , Teste de Materiais
5.
Int J Mol Sci ; 24(21)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37958615

RESUMO

This study investigated the impact of various enhancers on permeation through the skin and accumulation in the skin from acrylic pressure-sensitive adhesive-based drug-in-adhesives matrix-type transdermal patches. Eleven patches, each containing a 5% enhancer of permeation, encompassing compounds such as salicylic acid, menthol, urea, glycolic acid, allantoin, oleic acid, Tween 80, linolenic acid, camphor, N-dodecylcaprolactam, and glycerin, were developed. Ibuprofen (IBU) was the model active substance, a widely-used non-steroidal anti-inflammatory drug. The results were compared to patches without enhancers and commercial preparations. The study aimed to assess the effect of enhancers on IBU permeability. The adhesive properties of the patches were characterised, and active substance permeability was tested. The findings revealed that patches with 5% allantoin exhibited the highest IBU permeability, approximately 2.8 times greater than patches without enhancers after 24 h. These patches present a potential alternative to commercial preparations, highlighting the significant impact of enhancers on transdermal drug delivery efficiency.


Assuntos
Alantoína , Ibuprofeno , Ibuprofeno/farmacologia , Alantoína/metabolismo , Administração Cutânea , Pele/metabolismo , Absorção Cutânea , Adesivos/metabolismo
7.
Science ; 382(6672): 779-780, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37972173

RESUMO

Illuminating the path to degrading troublesome proteins.


Assuntos
Adesivos , Adesivos Teciduais
8.
Photobiomodul Photomed Laser Surg ; 41(11): 608-621, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37910776

RESUMO

Objective: This systematic review and meta-analysis aimed to assess the influence of laser treatment on adhesive bonding of liners to polymethyl methacrylate (PMMA) denture base resins. Methods: The focused question was: "Does the application of laser treatment (Intervention) influence the adhesive bonding strength (Outcome) of liners to PMMA denture base resins (Population) as compared with untreated or unconditioned surfaces (Control)?" In vitro and clinical reports as well as reports on influence of laser treatments on bonding strength of liners to PMMA denture resins in comparison with untreated surfaces were included. Reports without any control group[s], without any application of laser[s] for PMMA denture bases that did not utilize PMMA denture bases, and not evaluate bond strength of PMMA denture base resins were excluded. An electronic search was conducted on PubMed, Scopus, and Web of Science. Meta-analyses were performed for calculating the standard mean difference (SMD) with a 95% confidence interval (95% CI). Results: Nine of the 12 included studies found that laser irradiation treatment produced significant surface texture alterations of the PMMA denture base and improved the adhesion between the PMMA denture base and soft lining. According to the meta-analysis, tensile bond strength showed an SMD of -2.49% (95% CI: -3.89 to -1.08; p = 0.0005), suggesting a statistically significant difference between the control and test groups (i.e., favoring laser-treated samples than untreated samples). Regarding shear bond strength scores, the outcomes showed an SMD of -2.24% (95% CI: -3.79 to -0.69; p = 0.005), suggesting a statistically significant difference between the control and test groups (i.e., favoring laser-treated samples than untreated samples). Conclusions: Despite the high heterogeneity among the included studies, it can be concluded that laser treatment might improve the bonding strengths of liners to PMMA denture base resins as compared with untreated surfaces. To validate the aforementioned conclusions, further verification is required through the implementation of well-designed randomized controlled trials with large sample sizes.


Assuntos
Reembasadores de Dentadura , Polimetil Metacrilato , Polimetil Metacrilato/química , Adesivos , Resinas Acrílicas/química , Teste de Materiais , Bases de Dentadura
9.
PLoS One ; 18(11): e0294076, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37956149

RESUMO

INTRODUCTION: Root canal sealing materials play a crucial role in an endodontic procedure by forming a bond between the dentinal walls and the gutta-percha. The current study aims to analyse the dentinal tubule penetration and adhesive pattern, including the push-out bond strength of six commercially available root canal sealers. METHODOLOGY: Eighty-four mandibular first premolars were split into seven groups (and n = 12), Group 1: Dia-Root, Group 2: One-Fil, Group 3: BioRoot RCS, Group 4: AH Plus, Group 5: CeraSeal, Group 6: iRoot SP, Group 7: GP without sealer (control). Two groups were made, one for dentinal tubule penetration and the other for push-out bond strength; the total sample size was one hundred sixty-eight. Root canal treatment was performed using a method called the crown down technique, and for obturation, the single cone technique was used. A confocal laser scanning microscope (Leica, Microsystem Heidel GmbH, Version 2.00 build 0585, Germany) was used to evaluate dentinal tubule penetration, and Universal Testing Machine was utilised to measure the push-out bond strength (Shimadzu, Japan) using a plunger size of 0.4 mm and speed of 1mm/min. Finally, the adhesive pattern of the sealers was analysed by HIROX digital microscope (KH-7700). Statistical analysis was carried out by a one-way Anova test, Dunnet's T3 test, and Chi-square test. RESULTS: Highest dentinal tubule penetration was noticed with One-Fil (p<0.05), followed by iRoot SP, CeraSeal, AH Plus, Dia-Root also, the most negligible value was recorded for BioRoot RCS. Meanwhile, BioRoot RCS (p<0.05) demonstrated the greater value of mean push-out bond strength, followed by One-fil, iRoot SP, CeraSeal, AH Plus and Dia-Root. Regarding adhesive pattern, most of the samples were classified as type 3 and type 4 which implies greater sealing ability and better adherence to the dentinal wall. However, BioRoot RCS revealed the most type 4 (p<0.05), followed by AH Plus, One-Fil, CeraSeal and Dia-Root. CONCLUSION: The highest dentinal tubule penetration was shown by One-Fil compared to other groups. Meanwhile, BioRoot RCS had greater push-out bond strength and more adhesive pattern than other tested materials.


Assuntos
Adesivos , Materiais Restauradores do Canal Radicular , Dentina , Teste de Materiais , Materiais Restauradores do Canal Radicular/química , Resinas Epóxi , Guta-Percha/química
10.
Stomatologiia (Mosk) ; 102(6): 62-67, 2023.
Artigo em Russo | MEDLINE | ID: mdl-37997315

RESUMO

This review presents an analysis of domestic and foreign literature on the issues of fixation of facial epitheses and combined maxillofacial prostheses, such as the use of craniofacial implants installed in the zygomatic bone, brow arches, orbital walls, mastoid process of the temporal bone with beam or magnetic beam fixation systems. The advantages and disadvantages of such fastening systems are described. The analysis and systematization of available data on medical adhesive compositions that can be used in maxillofacial prosthetics to hold facial epitheses has been carried out. Much attention is paid to the chemical composition of pressure-sensitive adhesives, water-based and silicone-based. Examples of such compositions are given. The physicochemical properties of medical adhesive systems that cause adhesive-cohesive interaction are described. This review presents the results of comparative studies to assess the fixing properties of various adhesives, as well as to study the formation of biofilm on the surfaces of prostheses and skin when using different adhesives.


Assuntos
Implantes Dentários , Prótese Maxilofacial , Humanos , Cimentos Dentários , Face/cirurgia , Silicones , Adesivos/química
11.
Nat Commun ; 14(1): 7707, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38001112

RESUMO

Oral ulcer can be treated with diverse biomaterials loading drugs or cytokines. However, most patients do not benefit from these materials because of poor adhesion, short-time retention in oral cavity and low drug therapeutic efficacy. Here we report a self-stabilized and water-responsive deliverable coenzyme salt polymer poly(sodium α-lipoate) (PolyLA-Na)/coenzyme polymer poly(α-lipoic acid) (PolyLA) binary synergistic elastomer adhesive patch, where hydrogen bonding cross-links between PolyLA and PolyLA-Na prevents PolyLA depolymerization and slow down the dissociation of PolyLA-Na, thus allowing water-responsive sustainable delivery of bioactive LA-based small molecules and durable adhesion to oral mucosal wound due to the adhesive action of PolyLA. In the model of mice and mini-pig oral ulcer, the adhesive patch accelerates the healing of the ulcer by regulating the damaged tissue inflammatory environment, maintaining the stability of oral microbiota, and promoting faster re-epithelialization and angiogenesis. This binary synergistic patch provided a therapeutic strategy to treat oral ulcer.


Assuntos
Úlceras Orais , Humanos , Animais , Suínos , Úlceras Orais/tratamento farmacológico , Polímeros , Adesivos , Elastômeros , Porco Miniatura
12.
Int J Mol Sci ; 24(22)2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-38003425

RESUMO

The treatment and surgical repair of torn Achilles tendons seldom return the wounded tendon to its original elasticity and stiffness. This study explored the in vitro and in vivo simultaneous release of indomethacin and bupivacaine from electrospun polylactide-polyglycolide composite membranes for their capacity to repair torn Achilles tendons. These membranes were fabricated by mixing polylactide-polyglycolide/indomethacin, polylactide-polyglycolide/collagen, and polylactide-polyglycolide/bupivacaine with 1,1,1,3,3,3-hexafluoro-2-propanol into sandwich-structured composites. Subsequently, the in vitro pharmaceutic release rates over 30 days were determined, and the in vivo release behavior and effectiveness of the loaded drugs were assessed using an animal surgical model. High concentrations of indomethacin and bupivacaine were released for over four weeks. The released pharmaceutics resulted in complete recovery of rat tendons, and the nanofibrous composite membranes exhibited exceptional mechanical strength. Additionally, the anti-adhesion capacity of the developed membrane was confirmed. Using the electrospinning technique developed in this study, we plan on manufacturing degradable composite membranes for tendon healing, which can deliver sustained pharmaceutical release and provide a collagenous habitat.


Assuntos
Nanofibras , Traumatismos dos Tendões , Ratos , Animais , Indometacina , Bupivacaína , Adesivos , Traumatismos dos Tendões/tratamento farmacológico , Traumatismos dos Tendões/cirurgia , Ácido Poliglicólico , Tendões
13.
J Mater Chem B ; 11(45): 10845-10858, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37937417

RESUMO

Healing large-scale wounds has been a long-standing challenge in the field of biomedicine. Herein, we propose an injectable oxidated sodium alginate/gelatin/3,3'-dithiobis(propionic hydrazide)-aurum (Alg-CHO/gelatin/DTPH-Au) hydrogel filler with asymmetric adhesion ability and removability, which is formed by the Schiff-base reaction between aldehyde-based sodium alginate and multi-amino crosslinkers (gelatin and DTPH), combined with the coordination interaction between Au nanoparticles and disulfide bond of DTPH. Consequently, the prepared Alg-CHO/gelatin/DTPH-Au hydrogel exhibits high mechanical properties and injectable behaviors owing to its multiple-crosslinked interactions. Moreover, because various types of interaction bonding form on the contact side with the tissue, denser crosslinking of the upper layer relative to the lower layer occurs. Combined with the temperature difference between the upper and lower surfaces, this results in asymmetric adhesive properties. Owing to the photothermal effect, the reversible coordination interaction between Au nanoparticles and DTPH and the change in the triple helix structure of gelatin to a coil structure impart the filler-phased removability and antibacterial ability. The choice of all natural polymers also allows for favorable degradability of the wound filler and outstanding biocompatibility. Based on these features, this versatile wound filler can achieve a wide range of applications in the field of all-skin wound repair.


Assuntos
Hidrogéis , Nanopartículas Metálicas , Hidrogéis/química , Adesivos , Gelatina/química , Ouro , Cicatrização , Alginatos/química
14.
J Adhes Dent ; 25(1): 241-256, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37975313

RESUMO

PURPOSE: To investigate the bonding performance of three universal adhesives (UAs) to dentin and the effect of different curing modes and hydrofluoric-acid (HF) etching of lithium-disilicate glass-ceramic on the adhesive performance of two UA/composite cement (CC) combinations. MATERIALS AND METHODS: In the first project part, the immediate and aged (25k and 50k thermocycles) microtensile bond strength (µTBS) of the two light-curing UAs G2-Bond Universal (G2B; GC) and Scotchbond Universal Plus (SBUp; 3M Oral Care), and the self-curing UA Tokuyama Universal Bond II (TUBII; Tokuyama) to flat dentin was measured, when applied in both E&R and SE bonding mode using a split-tooth design (n = 10). The resultant adhesive-dentin interfaces were characterized using TEM. In the second project part, CAD/CAM composite blocks were luted to flat dentin with either Scotchbond Universal Plus/RelyX Universal (SBUp/RxU; 3M Oral Care) or Tokuyama Universal Bond II/Estecem II Plus (TUBII/ECIIp; Tokuyama Dental) using different curing modes (AA mode: auto-curing of both adhesive and cement; AL mode: auto-curing of adhesive and light-curing of cement), upon which their immediate and aged (25k and 50k thermocycles) µTBS was measured. In the third project part, the same UA/CC combinations were luted to CAD/CAM glass-ceramic to measure their immediate and aged (6-month water storage) shear bond strength (SBS). RESULTS: In E&R bonding mode, the performance of G2B, SBUp and TUBII was not significantly different in terms of µTBS, while G2B and SBUp significantly outperformed TUBII in SE bonding mode. No significant difference in µTBS was found between the SBUp/RxU and TUBII/ECIIp UA/CC combinations, regardless of bonding mode, aging time, or curing mode. The cement-curing mode did not significantly influence µTBS, while a significantly higher µTBS was recorded for the UA/CC combinations applied in E&R bonding mode. HF significantly improved the SBS of the UA/CC combinations to glass-ceramic. CONCLUSION: The self-curing adhesive performed better when applied in E&R than in SE bonding mode. The curing mode did not influence the adhesive performance of the composite cements, while an E&R bonding mode rendered more favorable adhesion in a self-curing luting protocol. When bonding to glass-ceramic, the adhesive performance of the universal adhesive/composite cement combinations benefited from HF etching.


Assuntos
Colagem Dentária , Cimentos Dentários , Cimentos Dentários/química , Cimentos de Resina/química , Colagem Dentária/métodos , Cimentos de Ionômeros de Vidro , Teste de Materiais , Resistência à Tração , Adesivos Dentinários/química , Adesivos , Dentina
15.
J Nanobiotechnology ; 21(1): 407, 2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-37924105

RESUMO

Rapid hemostasis of uncontrolled bleeding following traumatic injuries, especially accompanied by coagulopathies, remains a significant clinical challenge. Extracellular vesicles (EVs) show therapeutic effects for fast clotting. However, low yield, specific storage conditions, and lack of proper carriers have hindered EVs' clinical application. Herein, we establish an optimized procedure method to generate lyophilized mesenchymal stem cell-derived apoptotic vesicles (apoVs) with adhesive hydrogel sponge to show superior procoagulant activity for traumatic hemorrhage. Mechanistically, apoVs' procoagulant ability stems from their high tissue factor (TF) and phosphatidylserine (PS) expression independent of hemocytes and circulating procoagulant microparticles (cMPs). Their stable hemostatic capability was maintained after 2-month room temperature storage. Subsequently, we mixed apoVs with both phenylboronic acid grafted oxidized hyaluronic acid (PBA-HA) and poly(vinyl alcohol) (PVA) simultaneously, followed by lyophilization to construct a novel apoV-encapsulated hydrogel sponge (apoV-HS). Compared to commercial hemostats, apoV-HS exhibits rapid procoagulant ability in liver-laceration and femoral artery hemorrhage in rat and rabbit models of coagulopathies. The combination of high productivity, physiological stability, injectability, plasticity, excellent adhesivity, biocompatibility, and rapid coagulant property indicates that apoV-HS is a promising therapeutic approach for heavy hemorrhage in civilian and military populations.


Assuntos
Vesículas Extracelulares , Hemostáticos , Ratos , Animais , Coelhos , Adesivos , Hidrogéis , Hemostáticos/farmacologia , Hemorragia/tratamento farmacológico
16.
Clin. transl. oncol. (Print) ; 25(10): 2931-2937, oct. 2023. ilus
Artigo em Inglês | IBECS | ID: ibc-225074

RESUMO

Purpose To explore the application value of CT-guided localization using a coil in combination with medical adhesive in sublobar resection. Methods The clinical data of 90 patients who had small pulmonary nodules and received thoracoscopic sublobar resection during the period from September 2021 to October 2022 in the Department of Thoracic Surgery, Juxian People’s Hospital, Shandong Province, were retrospectively analyzed. Results The diameters of 95 pulmonary nodules in the 90 patients in the whole group ranged from 0.40 to 1.24 cm, and their distances from the visceral pleura ranged from 0.51 to 2.15 cm. In these patients, percutaneous lung puncture was successfully performed under local anesthesia, through which coils were implanted in the nodules and medical adhesive was injected around the nodules, with a success rate of localization of 100%. Localization complications included 10 cases of asymptomatic pneumothorax, 9 cases of intrapulmonary hemorrhage, 5 cases of severe pain, and 1 case of pleural reaction, all of which required no special treatment. After preoperative localization, the success rate of resection of pulmonary nodules was 100%, and sufficient surgical margins were obtained. Conclusion CT-guided localization using a coil in combination with medical adhesive is a safe, effective, and simple localization method that can meet the requirements of thoracic surgeons for intraoperative localization; for small pulmonary nodules, especially those small-sized and deep-located ground-glass nodules containing few solid mass, this method has important clinical application value, which is a preoperative localization technique worthy of wide application in clinical practice (AU)


Assuntos
Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/cirurgia , Nódulos Pulmonares Múltiplos/cirurgia , Nódulo Pulmonar Solitário/cirurgia , Adesivos , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
17.
ACS Appl Mater Interfaces ; 15(43): 50095-50105, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37871154

RESUMO

Tissue wounds are a significant challenge for the healthcare system, affecting millions globally. Current methods like suturing and stapling have limitations as they inadequately cover the wound, fail to prevent fluid leakage, and increase the risk of infection. Effective solutions for diverse wound conditions are still lacking. Adhesive hydrogels, on the other hand, can be a potential alternative for wound care. They offer benefits such as firm sealing without leakage, easy and rapid application, and the provision of mechanical support and flexibility. However, the in vivo durability of hydrogels is often compromised by excessive swelling and unforeseen degradation, which limits their widespread use. In this study, we addressed the durability issues of the adhesive hydrogels by incorporating acrylamide polyethylene glycol N-hydroxysuccinimide (PEG-NHS) moieties (max. 2 wt %) into hydrogels based on hydroxy ethyl acrylamide (HEAam). The results showed that the addition of PEG-NHS significantly enhanced the adhesion performance, achieving up to 2-fold improvement on various soft tissues including skin, trachea, heart, lung, liver, and kidney. We further observed that the addition of PEG-NHS into the adhesive hydrogel network improved their intrinsic mechanical properties. The tensile modulus of these hydrogels increased up to 5-fold, while the swelling ratio decreased up to 2-fold in various media. These hydrogels also exhibited improved durability under the enzymatic and oxidative biodegradation induced conditions without causing any toxicity to the cells. To evaluate its potential for clinical applications, we used PEG-NHS based hydrogels to address tracheomalacia, a condition characterized by inadequate mechanical support of the airway due to weak/malacic cartilage rings. Ex vivo study confirmed that the addition of PEG-NHS to the hydrogel network prevented approximately 90% of airway collapse compared to the case without PEG-NHS. Overall, this study offers a promising approach to enhance the durability of adhesive hydrogels by the addition of PEG-NHS, thereby improving their overall performances for various biomedical applications.


Assuntos
Hidrogéis , Polietilenoglicóis , Polietilenoglicóis/farmacologia , Hidrogéis/farmacologia , Adesivos , Medicina Estatal , Materiais Biocompatíveis , Acrilamidas
18.
ACS Appl Mater Interfaces ; 15(43): 49931-49942, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37856675

RESUMO

The skin secretion of Andrias davidianus (SSAD) is a novel biological adhesive raw material under development. This material exhibits robust adhesion while maintaining the flexibility of the wound. It also has the potential for large-scale production, making it promising for practical application explore. Hence, in-depth research on methods to fine-tune SSAD properties is of great importance to promote its practical applications. Herein, we aim to enhance the adhesive and healing properties of SSAD by incorporating functional components. To achieve this goal, we selected 3,4-dihydroxy-l-phenylalanine and vaccarin as the functional components and mixed them with SSAD, resulting in a new bioadhesive, namely, a formulation termed "enhanced SSAD" (ESSAD). We found that the ESSAD exhibited superior adhesive properties, and its adhesive strength was improved compared with the SSAD. Moreover, ESSAD demonstrated a remarkable ability to promote wound healing. This study presents an SSAD-based bioadhesive formulation with enhanced properties, affirming the feasibility of developing SSAD-based adhesive materials with excellent performance and providing new evidence for the application of SSAD. This study also aims to show that SSAD can be mixed with other substances, and addition of effective components to SSAD can be studied to further adjust or improve its performance.


Assuntos
Adesivos Teciduais , Cicatrização , Humanos , Adesivos/farmacologia , Pele , Adesivos Teciduais/farmacologia , Aderências Teciduais , Muco , Hidrogéis
19.
ACS Appl Bio Mater ; 6(10): 4002-4019, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37795994

RESUMO

Stimulus-responsive dry adhesives, inspired by the adhesive mechanisms displayed by the fibrillar structures present on the feet of geckos, have emerged as a promising area of research for applications such as robotic grippers and climbing robots. These stimulus-responsive dry adhesives exhibit some unique capabilities, as their ability to adhere to and detach from surfaces can be controlled with the help of an external stimulus. For example, studies have developed magnetic field-responsive dry adhesives and show that the adhesion of these materials can be turned on and off by controlling the applied magnetic field. Light-responsive adhesives have also been developed and shown to reverse their adhesion using infrared light as the stimulus. Such materials show tremendous promise in pick-and-place systems for handling delicate objects and microelectronic products. The focus of this article is to review the stimulus-responsive materials that have been used to develop dry adhesives. The mechanisms adopted by these stimulus-responsive materials to switch their adhesion are discussed. Applications of stimulus-responsive dry adhesives are presented, and last, the future perspective of these materials is discussed.


Assuntos
Adesivos , Lagartos , Animais , Adesivos/química , Campos Magnéticos
20.
Georgian Med News ; (340-341): 113-121, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37805884

RESUMO

OBJECTIVES: the study aims to assess the shear bond strength of modified- 3M orthodontic adhesive Transbond™ XT with different concentrations of Titanium Dioxide and zirconium oxide nanoparticles. In a retrospective cross-sectional study a hundred sound-extracted human upper premolars were collected. 3M orthodontic adhesive Transbond™ XT was modified by (0,02%, 0.04%, and 0.06% Zirconium Oxide), and (0,02%, 0.04%, and 0.06% Titanium Dioxide) nanoparticles, and (0,02%, 0.04%, and 0.06% Zirconium Oxide and Titanium Dioxide). dentaurum discovery pearl ceramic bracket were bonded to buccal enamel surfaces of the samples of control and nine modified adhesive groups. At 24 h after bonding, shear bond strength was measured. Adhesive remnant index was scored under (10X) magnification power of stereomicroscope after de-bonding. The chemical characteristics of orthodontic adhesive material were explored before and after mixing with Titanium Dioxide and zirconium oxide nanoparticles by using FTIR. (Zirconium Oxide nanoparticles) group and combination (Zirconium Oxide and Titanium Dioxide nanoparticles) had a higher shear bond strength mean value than the control group, 0.06% combination (Zirconium Oxide and Titanium Dioxide nanoparticles) group had the highest mean value. About adhesive remnant index, no significant differences were found among the studying groups. The addition of 0.06% combination (Zirconium Oxide and Titanium Dioxide nanoparticles) had the best performance and improved shear bond strength of 3M orthodontic adhesive Transbond™ XT.


Assuntos
Colagem Dentária , Nanopartículas , Humanos , Estudos Transversais , Estudos Retrospectivos , Técnicas In Vitro , Teste de Materiais , Adesivos , Cimentos Dentários , Propriedades de Superfície
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