Advanced ethylene-absorbing and cushioning depending on the 3D porous-structured fruit packaging: Toward polyurethane foam manipulation using zein and soybean oil polyol substrates.

Fruits are essential sources of nutrients in our daily diet; however, their spoilage is often intensified by mechanical damage and the ethylene phytohormone, resulting in significant economic losses and exacerbating hunger issues. To address these challenges, this study presented a straightforward in situ synthesis protocol for producing Z/SOPPU foam, a 3D porous-structured fruit packaging. This innovative packaging material offered advanced ethylene-adsorbing and cushioning capabilities achieved through stirring, heating, and standing treatments. The results demonstrated that the Z/SOPPU foam, with its porous structure, served as an excellent packaging material for fruits, maintaining the intact appearance of tomatoes even after being thrown 72 times from a height of 1.5 m. Additionally, it exhibited desirable hydrophobicity (contact angle of 114.31 ± 0.82°), degradability (2.73 ± 0.88 % per 4 weeks), and efficient ethylene adsorption (adsorption rate of 13.2 ± 1.7 mg/m3/h). These remarkable characteristics could be attributed to the unique 3D micron-porous configuration, consisting of soybean oil polyol polyurethane foam for mechanical strain cushioning and zein for enhanced ethylene adsorption efficiency. Overall, this research offers an effective and original approach to the rational design and fabrication of advanced bio-based fruit packaging.

Graphene nanosheet reinforcement of polyurethane nanocomposite for green and sustainable photoluminescence, superhydrophobic, and anticorrosive paint.

A simple and environmentally friendly method was developed for smart and efficient waterborne polyurethane (PUR) paint. Sugarcane bagasse was recycled into reduced graphene oxide nanosheets (rGONSs). Both lanthanide-doped aluminate nanoparticles (LAN; photoluminescent agent, 7-9 nm) and rGONSs (reinforcement agent) were integrated into a waterborne polyurethane to produce a novel photoluminescent, hydrophobic, and anticorrosive nanocomposite coating. Using ferrocene-based oxidation under masked circumstances, graphene oxide nanosheets were produced from sugarcane bagasse. The oxidized semicarbazide (SCB) nanostructures were integrated into polyurethane coatings as a drying, anticorrosion, and crosslinking agent. Polyurethane coatings with varying amounts of phosphor pigment were prepared and subsequently applied to mild steel. The produced paints (LAN/rGONSs@PUR) were tested for their hydrophobicity, hardness, and scratch resistance. Commission Internationale de l'éclairage (CIE) Laboratory parameters and photoluminescence analysis established the opacity and colourimetric properties of the nanocomposite coatings. When excited at 365 nm, the luminescent transparent paints emitted a strong greenish light at 517 nm. The anticorrosion characteristics of the coated steel were investigated. The phosphor-containing (11% w/w) polyurethane coatings displayed the most pronounced anticorrosion capability and long-persistent luminosity. The prepared waterborne polyurethane paints were very photostable and durable.

Dental biomaterials redefined: molecular docking and dynamics-driven dental resin composite optimization.

BACKGROUND: Dental resin-based composites are widely recognized for their aesthetic appeal and adhesive properties, which make them integral to modern restorative dentistry. Despite their advantages, adhesion and biomechanical performance challenges persist, necessitating innovative strategies for improvement. This study addressed the challenges associated with adhesion and biomechanical properties in dental resin-based composites by employing molecular docking and dynamics simulation. METHODS: Molecular docking assesses the binding energies and provides valuable insights into the interactions between monomers, fillers, and coupling agents. This investigation prioritizes SiO2 and TRIS, considering their consistent influence. Molecular dynamics simulations, executed with the Forcite module and COMPASS II force field, extend the analysis to the mechanical properties of dental composite complexes. The simulations encompassed energy minimization, controlled NVT and NPT ensemble simulations, and equilibration stages. Notably, the molecular dynamics simulations spanned a duration of 50 ns. RESULTS: SiO2 and TRIS consistently emerged as influential components, showcasing their versatility in promoting solid interactions. A correlation matrix underscores the significant roles of van der Waals and desolvation energies in determining the overall binding energy. Molecular dynamics simulations provide in-depth insights into the mechanical properties of dental composite complexes. HEMA-SiO2-TRIS excelled in stiffness, BisGMA-SiO2-TRIS prevailed in terms of flexural strength, and EBPADMA-SiO2-TRIS offered a balanced combination of mechanical properties. CONCLUSION: These findings provide valuable insights into optimizing dental composites tailored to diverse clinical requirements. While EBPADMA-SiO2-TRIS demonstrates distinct strengths, this study emphasizes the need for further research. Future investigations should validate the computational findings experimentally and assess the material's response to dynamic environmental factors.

Electrical aligned polyurethane nerve guidance conduit modulates macrophage polarization and facilitates immunoregulatory peripheral nerve regeneration.

Biomaterials can modulate the local immune microenvironments to promote peripheral nerve regeneration. Inspired by the spatial orderly distribution and endogenous electric field of nerve fibers, we aimed to investigate the synergistic effects of electrical and topological cues on immune microenvironments of peripheral nerve regeneration. Nerve guidance conduits (NGCs) with aligned electrospun nanofibers were fabricated using a polyurethane copolymer containing a conductive aniline trimer and degradable L-lysine (PUAT). In vitro experiments showed that the aligned PUAT (A-PUAT) membranes promoted the recruitment of macrophages and induced their polarization towards the pro-healing M2 phenotype, which subsequently facilitated the migration and myelination of Schwann cells. Furthermore, NGCs fabricated from A-PUAT increased the proportion of pro-healing macrophages and improved peripheral nerve regeneration in a rat model of sciatic nerve injury. In conclusion, this study demonstrated the potential application of NGCs in peripheral nerve regeneration from an immunomodulatory perspective and revealed A-PUAT as a clinically-actionable strategy for peripheral nerve injury.

Exploring the synergistic effect of carboxymethyl cellulose and chitosan in enhancing thermal stability of polyurethanes through statistical mixture design approach.

The thermal stability of polyurethanes, known for its limitations, was addressed in this research by seeking improvement through the introduction of carbohydrate-based chain extenders. In this research paper, we systematically sought to improve the thermal resistance of polyurethanes by incorporating carboxymethyl cellulose and chitosan, representing a pioneering application of the mixture design approach in their preparation. In this synthesis, hydroxyl-terminated polybutadiene and isophorone diisocyanate (IPDI) were reacted to prepare -NCO terminated prepolymer, which was subsequently reacted with varying mole ratios of CMC and CSN to develop a series of five PU samples. The prepared PU samples were characterized using the Fourier-transformed infrared spectroscopic technique. Thermal pyrolysis of PU samples was examined using thermal gravimetric analysis (TGA). It was observed that, among all the samples, PUS-3 showed remarkable thermal stability over a wide temperature range. A comprehensive statistical analysis was conducted to substantiate the experimental findings. It was estimated that CMC and CSN significantly enhance the thermal stability of the samples when involved in an interaction fashion. The ANOVA Table for the mixture design demonstrates that over 90 % of the total variation in thermal stability is explained by the mixture model across a wide temperature range. Moreover, PSU-3 exhibited 4 % more thermal stability over a wide range of temperatures on average, as compared to contemporary samples.

Bio-based P-N flame retardant with ZIF-67 in-situ growth on flexible polyurethane foam with excellent fire safety performance.

The wide application of flexible polyurethane foam (FPUF) poses a giant challenge to human society in terms of fire prevention and environmental pollution. To solve this problem, the lignocellulose-based P-N flame retardant (LFPN) has been developed using mechanochemical methods. It was found that FPUF treated using LFPN exhibited good flame retardancy, but suffered from high smoke generation and toxicity. The hollow dodecahedral ZIF-67 has been used for smoke suppression catalysis, but the agglomeration phenomenon makes it inefficient. Hence, in this study, the adhesive properties of polydopamine (PDA) were utilized to assist the in-situ growth of ZIF-67. The results showed that the total smoke release rate of the treated FPUF was reduced by 40.5%. The toxic gases, such as carbon monoxide (CO), hydrogen cyanide, etc., also showed the same decreasing trend. What's more, the catalytic effect of ZIF-67 itself and the synergistic effect with LFPN gave FPUF great flame retardant and smoke inhibition properties. This novel FPUF provides a new reference for achieving smoke suppression and toxicity reduction.

Development and performance evaluation of a novel elastic bacterial nanocellulose/polyurethane small caliber artificial blood vessels.

There is an increasing demand for small-diameter blood vessels. Currently, there is no clinically available small-diameter artificial vessel. Bacterial nanocellulose (BNC) has vast potential for applications in artificial blood vessels due to its good biocompatibility. At the same time, medical polyurethane (PU) is a highly elastic polymer material widely used in artificial blood vessels. This study reports a composite small-diameter BNC/PU conduit using a non-solvent-induced phase separation method with the highly hydrophilic BNC tube as the skeleton and the hydrophobic polycarbonate PU as the filling material. The results revealed that the compliance and mechanical matching of BNC/PU tubes were higher than BNC tubes; the axial/radial mechanical strength, burst pressure, and suture strength were significantly improved; the blood compatibility and cell compatibility were also excellent. The molecular and subcutaneous embedding tests showed that the composite tubes had lighter inflammatory reactions. The results of the animal substitution experiments showed that the BNC/PU tubes kept blood flow unobstructed without tissue proliferation after implantation in rats for 9 months. Thus, the BNC/PU small-diameter vascular prosthesis had the potential for long-term patency and acted as an ideal material for small-diameter vessels.

Silver nanowires/waterborne polyurethane composite film based piezoresistive pressure sensor for ultrasensitive human motion monitoring.

Flexible piezoresistive pressure sensors are gaining significant attention, particularly in the realm of flexible wearable electronic skin. Here, a flexible piezoresistive pressure sensor was developed with a broad sensing range and high sensitivity. We achieved this by curing polydimethylsiloxane (PDMS) on sandpaper, creating a PDMS film as the template with a micro-protrusion structure. The core sensing layer was formed using a composite of silver nanowires (AgNWs) and waterborne polyurethane (WPU) with a similar micro-protrusion structure. The sensor stands out with its exceptional sensitivity, showing a value of 1.04 × 106kPa-1with a wide linear range from 0 to 27 kPa. It also boasts a swift response and recovery time of 160 ms, coupled with a low detection threshold of 17 Pa. Even after undergoing more than 1000 cycles, the sensor continues to deliver stable performance. The flexible piezoresistive pressure sensor based on AgNWs/WPU composite film (AWCF) can detect small pressure changes such as pulse, swallowing, etc, which indicates that the sensor has great application potential in monitoring human movement and flexible wearable electronic skin.

Autotrophic denitrification by sulfur-based immobilized electron donor for enhanced nitrogen removal: Denitrification performance, microbial interspecific interaction and functional traits.

Sulfur-driven autotrophic denitrification (SdAD) is a promising nitrogen removing process, but its applications were generally constrained by conventional electron donors (i.e., thiosulfate (Na2S2O3)) with high valence and limited bioavailability. Herein, an immobilized electron donor by loading elemental sulfur on the surface of polyurethane foam (PFSF) was developed, and its feasibility for SdAD was investigated. The denitrification efficiency of PFSF was 97.3%, higher than that of Na2S2O3 (91.1%). Functional microorganisms (i.e., Thiobacillus and Sulfurimonas) and their metabolic activities (i.e., nir and nor) were substantially enhanced by PFSF. PFSF resulted in the enrichment of sulfate-reducing bacteria, which can reduce sulfate (SO42-). It attenuated the inhibitory effect of SO42-, whereas the generated product (hydrogen sulfide) also served as an electron donor for SdAD. According to the economic evaluation, PFSF exhibited strong market potential. This study proposes an efficient and low-cost immobilized electron donor for SdAD and provides theoretical support to its practical applications.

A liquid metal/polypyrrole electrospun TPU composite conductive network for highly sensitive strain sensing in human motion monitoring.

Developing soft wearable sensors with high sensitivity, low cost, and a wide monitoring range is crucial for monitoring human health. Despite advances in strain sensor technology, achieving high sensitivity and a wide operating range in a single device remains a major challenge in its design and preparation. Herein, a liquid metal (LM) is innovatively ultrasonically anchored to the gaps and surfaces of thermoplastic polyurethane (TPU) electrospun fibers, and then a conductive pathway is constructed through polypyrrole (PPy) self-polymerization to prepare a composite film. The strain sensor developed by ultrasonic anchoring and original polymerization technology shows a high strain coefficient (GF = 4.36 at 12.5% strain) and a low detection limit (less than 1% strain). Importantly, this sensor can monitor joint motion and subtle skin deformations in real time. In addition, the integration of strain sensors and N95 masks enables real-time monitoring of human respiration.

Catalytic Performance in Nitroarene Reduction of Nanocatalyst Based on Noble Metal Nanoparticles Supported on Polymer/s-Layer Protein Hybrids.

We present a novel bionanocatalyst fabricated by the adsorption-reduction of metal ions on a polyurethane/S-layer protein biotemplate. The bioinspired support was obtained by the adsorption of S-layer proteins (isolated from Lentilactobacillus kefiri) on polyurethane particles. Silver and platinum nanoparticles were well-loaded on the surface of the support after the combination with metallic salts and reduction with H2 at room temperature. Transmission electron microscopy analysis revealed the strawberry-like morphology of the bionanocatalysts with a particle size, dn, of 2.39 nm for platinum and 9.60 nm for silver. Both systems catalyzed the hydrogenation of p-nitrophenol to p-aminophenol with high efficiency in water at mild conditions in the presence of NaBH4. Three different amounts of bionanocatalyst were tested, and in all cases, conversions between 97 and 99% were observed. The catalysts displayed excellent recyclability over ten cycles, and no extensive damage in their nanostructure was noted after them. The bionanocatalysts were stable during their production, storage, and use, thanks to the fact that the biosupport provides an effective driving force in the formation and stabilization of the metallic nanoparticles. The successful bioinspired production strategy and the good catalytic ability of the systems are encouraging in the search for nontoxic, simple, clean, and eco-friendly procedures for the synthesis and exploitation of nanostructures.

Synthesis of lignin-based carbon/graphene oxide foam and its application as sensors for ammonia gas detection.

The present study highlights the integration of lignin with graphene oxide (GO) and its reduced form (rGO) as a significant advancement within the bio-based products industry. Lignin-phenol-formaldehyde (LPF) resin is used as a carbon source in polyurethane foams, with the addition of 1 %, 2 %, and 4 % of GO and rGO to produce carbon structures thus producing carbon foams (CFs). Two conversion routes are assessed: (i) direct addition with rGO solution, and (ii) GO reduction by heat treatment. Carbon foams are characterized by thermal, structural, and morphological analysis, alongside an assessment of their electrochemical behavior. The thermal decomposition of samples with GO is like those having rGO, indicating the effective removal of oxygen groups in GO by carbonization. The addition of GO and rGO significantly improved the electrochemical properties of CF, with the GO2% sensors displaying 39 % and 62 % larger electroactive area than control and rGO2% sensors, respectively. Furthermore, there is a significant electron transfer improvement in GO sensors, demonstrating a promising potential for ammonia detection. Detailed structural and performance analysis highlights the significant enhancement in electrochemical properties, paving the way for the development of advanced sensors for gas detection, particularly ammonia, with the prospective market demands for durable, simple, cost-effective, and efficient devices.

Comparative analysis of novel esophageal pressure monitoring catheters versus commercially available alternatives in a biomechanical model of the thoracic cavity.

Transpulmonary pressure can be estimated using esophageal balloon (EB) catheters, which come in a variety of manufacturing configurations. We assessed the performance of novel polyurethane EB designs, Aspisafe NG and NG+, against existing alternatives. We created a biomechanical model of the chest cavity using a plastic chamber and an ex-vivo porcine esophagus. The chamber was pressurized (- 20 and + 20 cmH2O) to simulate pleural pressures. We conducted tests with various EB inflation volumes and measured transesophageal pressure (TEP). TEP measurement was defined as accurate when the difference between pressure within the EB and chamber was 0 ± 1 cmH2O. We computed the minimal (Vaccuracy-min) and maximal (Vaccuracy-max) EB inflation volumes of accuracy. Inflation volumes were further validated using a surrogate method derived by the clinically validated positive pressure occlusion test (PPOT). When the esophageal balloons were filled with inflation volumes within the range provided by the manufacturers, the accuracy of TEP measurements was marginal. Our tests found median Vaccuracy-min across EB of 0.00-0.50 mL (p = 0.130), whereas Vaccuracy-max ranged 0.50-2.25 mL (p = 0.002). Post PPOT validation, median TEP was - 0.4 cmH2O (- 1.5 to 0.3) (p < 0.001 among catheters). The Aspisafe NG and NG+ were accurate in 81.7% and 77.8% of the measurements, respectively. We characterized two new EBs, which demonstrated good benchtop accuracy in TEP measurements. However, accuracy was notably influenced by the precise selection of EB inflation volumes.

Biocomposite thermoplastic polyurethanes containing evolved bacterial spores as living fillers to facilitate polymer disintegration.

The field of hybrid engineered living materials seeks to pair living organisms with synthetic materials to generate biocomposite materials with augmented function since living systems can provide highly-programmable and complex behavior. Engineered living materials have typically been fabricated using techniques in benign aqueous environments, limiting their application. In this work, biocomposite fabrication is demonstrated in which spores from polymer-degrading bacteria are incorporated into a thermoplastic polyurethane using high-temperature melt extrusion. Bacteria are engineered using adaptive laboratory evolution to improve their heat tolerance to ensure nearly complete cell survivability during manufacturing at 135 °C. Furthermore, the overall tensile properties of spore-filled thermoplastic polyurethanes are substantially improved, resulting in a significant improvement in toughness. The biocomposites facilitate disintegration in compost in the absence of a microbe-rich environment. Finally, embedded spores demonstrate a rationally programmed function, expressing green fluorescent protein. This research provides a scalable method to fabricate advanced biocomposite materials in industrially-compatible processes.

Sustainable polyurethane for the remediation of oil spills: a review.

Catastrophic oil spill is one of the major issues to the environment. Various methods have been used to treat oil spillage including in situ burning, the use of skimmers, dispersants, bioremediation, dispersing agents, oil sorbents, and biological agents. Application of oil sorbent is one of the effective solutions in oil spill clean-up. Polymers are sustainable extraordinary materials for the treatment of oil spillage due to their special physicochemical characteristics such as high porosity, good hydrophobicity, and reusability. Polymers are modified using suitable chemical reagents and their hydrophobicity is enhanced, making them suitable for oil spill clean-up. The present manuscript is an attempt to summarize the study of chemical modifications done on a polymer polyurethane (PU) for achieving the desirable properties, for efficient oil spill clean-up. A patent analysis has been carried out for the leading countries, top inventors, leading assignees, trends of patent publications, citation analysis, and summary of granted patents in the area of the use of a polymer Polyurethane (PU) for oil spill clean-up.

Polyurethane sponges bearing cucurbituril adsorb Cr(III) and Pb(II) ions from contaminated water samples.

Water contamination with toxic metals causes harmful effects on the environment and to human health. Although cucurbiturils have carboxyl groups in their portal that can interact with metal ions, there is a lack of studies about their use as metal adsorbent. This scenario has motivated conduction of the present study, which addresses the use of cucurbit[6]uril (CB[6]) and cucurbit[8]uril (CB[8]) for adsorbing Pb and Cr from water samples, in free forms and immobilized in poly(urethane) sponges. The adsorption kinetics revealed that CB[8] leads to faster adsorption compared to CB[6], with equilibrium achieved in 8 h for CB[8] and 48 h for CB[6] for both metals, and achieved up to 80% of decrease in metal concentration. The Langmuir isotherm model provided a better description of adsorption for Cr and Pb in CB[6] and Pb in CB[8] with a maximum concentration adsorbed of 32.47 mg g-1 for Pb in CB[6], while the Dubinin-Radushkevich model was more suitable for Cr adsorption in CB[8]. Sponges containing CB[6] and CB[8] have proven to be efficient for Pb and Cr remediation in tannery effluent samples, reducing Cr and Pb concentration by 42 and 33%, respectively. The results indicate that CB[6] and CB[8], whether used in their pure form or integrated into sponges, exhibit promising potential for efficiently adsorbing metals in aqueous contaminated environments.

Identification and characterization of a fungal cutinase-like enzyme CpCut1 from Cladosporium sp. P7 for polyurethane degradation.

Plastic degradation by biological systems emerges as a prospective avenue for addressing the pressing global concern of plastic waste accumulation. The intricate chemical compositions and diverse structural facets inherent to polyurethanes (PU) substantially increase the complexity associated with PU waste management. Despite the extensive research endeavors spanning over decades, most known enzymes exhibit a propensity for hydrolyzing waterborne PU dispersion (i.e., the commercial Impranil DLN-SD), with only a limited capacity for the degradation of bulky PU materials. Here, we report a novel cutinase (CpCut1) derived from Cladosporium sp. P7, which demonstrates remarkable efficiency in the degrading of various polyester-PU materials. After 12-h incubation at 55°C, CpCut1 was capable of degrading 40.5% and 20.6% of thermoplastic PU film and post-consumer foam, respectively, while achieving complete depolymerization of Impranil DLN-SD. Further analysis of the degradation intermediates suggested that the activity of CpCut1 primarily targeted the ester bonds within the PU soft segments. The versatile performance of CpCut1 against a spectrum of polyester-PU materials positions it as a promising candidate for the bio-recycling of waste plastics.IMPORTANCEPolyurethane (PU) has a complex chemical composition that frequently incorporates a variety of additives, which poses significant obstacles to biodegradability and recyclability. Recent advances have unveiled microbial degradation and enzymatic depolymerization as promising waste PU disposal strategies. In this study, we identified a gene encoding a cutinase from the PU-degrading fungus Cladosporium sp. P7, which allowed the expression, purification, and characterization of the recombinant enzyme CpCut1. Furthermore, this study identified the products derived from the CpCut1 catalyzed PU degradation and proposed its underlying mechanism. These findings highlight the potential of this newly discovered fungal cutinase as a remarkably efficient tool in the degradation of PU materials.

Core-Shell Structure of Photopolymer-Grafted Polyurethane as a Controlled Drug Delivery Vehicle for Biomedical Application.

Functionalized ultraviolet photocurable bisphenol A-glycerolate dimethacrylates with tailorable size have been synthesized as the core, which have further been grafted using the diisocyanate chain end of polyurethane (PU) as the shell to create a core-shell structure of tunable size for a controlled drug delivery vehicle. The core-shell structure has been elucidated through spectroscopic techniques like 1H NMR, FTIR, and UV-vis and their relative shape and size through TEM and AFM morphology. The greater cross-link density of the core is reflected in the higher glass transition temperature, and the improved thermal stability of the graft copolymer is proven from its thermogravimetric analyses. The flow behavior and enhanced strength of the graft copolymers have been revealed from rheological measurements. The graft copolymer exhibits sustained release of the drug, as compared to pure polyurethane and photopolymer, arising from its core-shell structure and strong interaction between the copolymer and drug, as observed through a significant shifting of absorption peaks in FTIR and UV-vis measurements. Biocompatibility has been tested for the real application of the novel graft copolymer in medical fields, as revealed from MTT assay, cell imaging, and cell adhesion studies. The efficacy of controlled release from a graft copolymer has been verified from the gradual cell killing and ∼70% killing in 3 days vs meager cell killing of ∼25% very quickly in 1 day, followed by the increased cell viability of the system treated with the pure drug. The mechanism of slow and controlled drug release from the core-shell structure has been explored. The fluorescence images support the higher cell-killing efficiency as opposed to a pure drug or a drug embedded in polyurethane. Cells seeded on 3D scaffolds have been developed by embedding a graft copolymer, and fluorescence imaging confirms the successful growth of cells within the scaffold, realizing the potential of the core-shell graft copolymer in the biomedical arena.

Large-Scale Wearable Textile-Based Sweat Sensor with High Sensitivity, Rapid Response, and Stable Electrochemical Performance.

Textile-based sweat sensors display great potential to enhance wearable comfort and health monitoring; however, their widespread application is severely hindered by the intricate manufacturing process and electrochemical characteristics. To address this challenge, we combined both impregnation coating technology and conjugated electrospinning technology to develop an electro-assisted impregnation core-spinning technology (EAICST), which enables us to simply construct a sheath-core electrochemical sensing yarn (TPFV/CPP yarn) via coating PEDOT:PSS-coated carbon fibers (CPP) with polyurethane (TPU)/polyacrylonitrile (PAN)/poloxamer (F127)/valinomycin as shell. The TPFV/CPP yarn was sewn into the fabric and integrated with a sensor to achieve a detachable feature and efficiently monitor K+ levels in sweat. By introducing EAICST, a speed of 10 m/h can be realized in the continuous preparation of the TPFV/CPP yarn, while the interconnected pores in the yarn sheath enable it to quickly capture and diffuse sweat. Besides, the sensor exhibited excellent sensitivity (54.26 mV/decade), fast response (1.7 s), anti-interference, and long-term stability (5000 s or more). Especially, it also possesses favorable washability and wear resistance properties. Taken together, this study provides a crucial technical foundation for the development of advanced wearable devices designed for sweat analysis.

Fabrication trueness and marginal quality of additively manufactured resin-based definitive laminate veneers with different restoration thicknesses.

OBJECTIVES: To evaluate how restoration thickness (0.5 mm and 0.7 mm) affects the fabrication trueness of additively manufactured definitive resin-based laminate veneers, and to analyze the effect of restoration thickness and margin location on margin quality. METHODS: Two maxillary central incisors were prepared either for a 0.5 mm- or 0.7 mm-thick laminate veneer. After acquiring the partial-arch scans of each preparation, laminate veneers were designed and stored as reference data. By using these reference data, a total of 30 resin-based laminate veneers were additively manufactured (n = 15 per thickness). All veneers were digitized and stored as test data. The reference and test data were superimposed to calculate the root mean square values at overall, external, intaglio, and marginal surfaces. The margin quality at labial, incisal, mesial, and distal surfaces was evaluated. Fabrication trueness at each surface was analyzed with independent t-tests, while 2-way analysis of variance was used to analyze the effect of thickness and margin location on margin quality (α = 0.05). RESULTS: Regardless of the evaluated surface, 0.7 mm-thick veneers had lower deviations (P < 0.001). Only the margin location (P < 0.001) affected the margin quality as labial margins had the lowest quality (P < 0.001). CONCLUSION: Restoration thickness affected the fabrication trueness of resin-based laminate veneers as 0.7 mm-thick veneers had significantly higher trueness. However, restoration thickness did not affect the margin quality and labial margins had the lowest quality. CLINICAL SIGNIFICANCE: Laminate veneers fabricated by using tested urethane-based acrylic resin may require less adjustment when fabricated in 0.7 mm thickness. However, marginal integrity issues may be encountered at the labial surface.