Polydimethylsiloxane Film Research Articles

Hyperbranched Thermosensitive Polymer-AuNP Composite Probe for Temperature Colorimetric Detection

Temperature detection is particularly important in the medical and scientific fields. Although there are various temperature detection methods, most of them focus on broad temperature detection, and basic research in specific fields, especially the detection of subtle temperature changes (32–34 °C) during wound infection, is still insufficient. For this purpose, a novel colorimetric temperature sensing probe is designed in this paper, which can quickly and intuitively respond to small temperature changes within a specific range through color changes. In this paper, hyperbranched polyethyleneimine (HPEI) was modified by isobutyrylation to prepare hyperbranched temperature-sensitive polymer (HPEI-IBAm). And it was combined with gold nanoparticles (AuNPs) prepared by a sodium citrate reduction method to construct an HPEI-IBAm-AuNP colorimetric probe. The probe exhibits excellent stability, even at salt concentrations of up to 12 g/L, thanks to the abundant amino functional groups and the large steric hindrance effect unique to HPEI-IBAm. In particular, the temperature detection range of the probe is precisely locked within 32–34 °C, enabling it to respond quickly and accurately to small temperature changes of only 2 °C. This feature is perfectly suited to the practical needs of temperature detection in infected wounds. The linear fitting coefficient of the temperature response is as high as 0.9929, ensuring the accuracy of the test results. The detection performance of the probe remained highly consistent over 10 cycles, fully proving its excellent reusability and durability. In addition, a flexible colorimetric sensor was prepared by combining the probe with polydimethylsiloxane (PDMS) film. This sensor is capable of rapidly detecting human skin temperature in real time, achieving an accuracy of 99.07% to 100.61%. It can provide a possible solution to the challenges of delayed and difficult temperature detection caused by different body parts and uneven surfaces, among others. This demonstrates its extensive practical value and potential, and it is expected to be further applied in the monitoring of wound infections.

Enhancing Passive Radiative Cooling Films with Hollow Yttrium-Oxide Spheres Insights from FDTD Simulation.

Passive daytime radiative cooling (PDRC) presents a promising avenue for efficient thermal management without relying on electrical power. In this study, the potential of integrating Hollow Yttrium-Oxide Spheres (HYSs) within a Polydimethylsiloxane (PDMS) matrix to enhance PDRC is investigated. Through a combination of experimental characterization and computational analysis, the optical properties and radiative cooling performance of PDMS films embedded with HYSs are evaluated. These results demonstrate that HYSs significantly improve both solar reflectivity and long-wave infrared (LWIR) emissivity of the PDMS matrix. Finite-Difference Time-Domain (FDTD) simulations confirm the scattering efficiency of HYSs across various wavelength ranges, highlighting their effectiveness as additives for enhancing the radiative properties of passive cooling materials. Experimental validation reveals enhanced reflectivity and emissivity of PDMS films with embedded HYSs, resulting in superior cooling performance compared to non-HYS counterparts. Overall, this study underscores the potential of HYS-infused PDMS films as a promising solution for passive radiative cooling, with broad applicability in diverse domains requiring efficient thermal management solutions. Additionally, these research insights pave the way for establishing an AI database for passive radiative cooling research, offering new avenues for further exploration and application in this field.

Nanocarbon and medicine: polymer/carbon nanotube composites for medical devices

AbstractIn view of wide-ranging application to the biomedical field, this work investigates the mechanical and electrical properties of a composite made of Single Wall Carbon Nanotubes (SWCNT) bundles self-grafted onto a poly-dimethyl-siloxane (PDMS) elastomer, particularly Sylgard 184, that has well assessed biocompatible properties and is commonly used in prosthetics. Due to the potential risks associated with the use of carbon nanostructures in implanted devices, we also assess the viability of cells directly grown on such composite substrates. Furthermore, as the stability of conductive, stretchable devices made of such composite is also crucial to their use in the medical field, we investigate, by different experimental techniques, the grafting of SWCNT bundles deep into PDMS films. Our findings prove that penetration of SWCNT bundles into the polymer bulk depends on heating time and carbon nanotubes can be seen beyond 150 μm from the surface. This is confirmed by direct electron microscopy observation of large bundles as deep as about 20 μm. The composites exhibit reliable mechanical and electrical responses that are more suitable to large and repeated deformation of the polymer with respect to thermoplastic based composites, suggesting a wide potential for their application to stretchable biomedical devices. Aiming at the proposed application of artificial bladders, a bladder prototype made of poly-dimethyl siloxane endowed with a printed SWCNT-based strain sensor was developed.

Development of a Photothermal Regenerative Plasmonic Platform as a Light-Controlled Interface.

This study introduces a novel plasmonic nanocomposite platform, where gold nanoparticles (AuNPs) are synthesized in situ within a polydimethylsiloxane (PDMS) film. The innovative fabrication process leverages ethyl acetate swelling to achieve a uniform distribution of AuNPs, eliminating the need for additional reagents. The resulting nanocomposite film exhibits exceptional photothermal conversion capabilities, efficiently converting absorbed light into heat and rapidly reaching high temperatures. Furthermore, the platform is biofunctionalized with the phosphotriesterase enzyme, not only enabling the degradation of organophosphate pesticides but also showcasing the potential for multifunctional applications. The platform's ability to be regenerated after use underscores its sustainability for repeated applications.

Finite element simulations of quartz crystal microbalances (QCM): from Sauerbrey to fractional viscoelasticity under water

2D finite element simulations are performed on QCM working in the thickness-shear mode and loaded with different homogeneous films. They include a purely elastic film, a viscoelastic Maxwellian liquid, viscoelastic-Voigt solid, and the fractional viscoelastic (power-law) version of each case. Unlike single-relaxation kind models, fractional viscoelasticity considers the relaxation-time spectrum often found in polymeric materials. The films are tested in air or covered with liquids of different viscosities. Two substrate thicknesses are tested: 100 nm and 500 nm, the latter being close to the condition that promotes the resonance of the adsorbed film. In all cases the simulations are compared with small-load approximation theory (SLA). The 100 nm films follow the theory closely, although significant deviations of the SLA are observed as the overtone number n increases, even in purely elastic films. We also show that it is possible to identify the viscoelastic ‘fingerprint’ of the 100 nm films in air using raw data and Sauerbrey’s equivalent thickness obtained with the QCM in the 3 < n < 13 range. These numerical data are validated by experimental measurements of crosslinked polydimethylsiloxane films with thicknesses ∼150 nm. In contrast, the 500 nm films deviate notoriously from the SLA, for all viscoelastic models and overtones, with the largest deviation observed in the elastic film. When a liquid layer covers the QCM without an adsorbed film, the only overtone that numerically reproduces the theoretical value is the fundamental, n = 1. For n > 1, strong coupling between the solid and liquid is detected, and the original vibration modes of the crystal are altered by the presence of the liquid. Finally, the numerical simulations suggest that it is possible to detect whether a viscoelastic film is formed under a liquid layer using only the information from n = 1. In these film/liquid systems we also observe the so-called missing-mass effect, although the theory and simulations exhibit different levels of impact of such effect when the liquid viscosity is high.

A deployable film method to enable replicable sampling of low-abundance environmental microbiomes

Urbanizing global populations spend over 90% of their time indoors where microbiome abundance and diversity are low. Chronic exposure to microbiomes with low abundance and diversity have demonstrated negative long-term impacts on human health. Sequencing-based analyses of environmental nucleic acids are critical to understanding the impact of the indoor microbiome on human health, however low DNA yields indoors, alongside sample collection and processing inconsistencies, currently challenge study replicability. This study presents a comparative assessment of a novel, passive, easily replicable sampling strategy using polydimethylsiloxane (PDMS) sheets alongside a representative swab-based collection protocol. Deployable, customizable PDMS films designed for whole-sample insertion into standardized extraction kits demonstrated 43% higher DNA yields per sample, and 76% higher yields per cm2 of sampler over swab-based protocols. These results indicate that this accessible, scalable method enables sufficient DNA collection to comprehensively evaluate indoor microbiome exposures and potential human health impacts using smaller, more space efficient samplers, representing an attractive alternative to swab-based collection. In addition, this process reduces the manual steps required for microbiome sampling which could address inter-study variability, transform the current microbiome sampling paradigm, and ultimately benefit the replicability and accessibility of microbiome exposure studies.

Controlled Ice Nucleation With a Sand-PDMS Film Device Enhances Cryopreservation of Mouse Preantral Ovarian Follicles.

Ovarian follicle cryopreservation is a promising strategy for fertility preservation; however, cryopreservation protocols have room for improvement to maximize post-thaw follicle viability and quality. Current slow-freezing protocols use either manual ice-seeding in combination with expensive programmable-rate freezers or other clinically incompatible ice initiators to control the ice-seeding temperature in the extracellular solution, a critical parameter that impacts post-cryopreservation cell/tissue quality. Previously, sand has been shown to be an excellent, biocompatible ice initiator, and its use in cryopreservation of human induced pluripotent stem cells enables high cell viability and quality after cryopreservation. This study applies sand as an ice initiator to cryopreserve multicellular microtissue, preantral ovarian follicles, using a simple slow-freezing protocol in the mouse model. Ovarian follicles cryopreserved using the sand partially embedded in polydimethylsiloxane (PDMS) film to seed ice in the extracellular solution exhibit healthy morphology, high viability, and the ability to grow similarly to fresh follicles in culture post-thaw. This sand-based cryopreservation strategy can facilitate convenient ovarian follicle cryopreservation using simple equipment, and this study further demonstrates the translatability of this strategy to not only single cells but also multicellular tissues.

Tailoring of Self-Healable Polydimethylsiloxane Films for Mechanical Energy Harvesting.

Triboelectric nanogenerators (TENGs) have emerged as potential energy sources, as they are capable of harvesting energy from low-frequency mechanical actions such as biological movements, moving parts of machines, mild wind, rain droplets, and others. However, periodic mechanical motion can have a detrimental effect on the triboelectric materials that constitute a TENG device. This study introduces a self-healable triboelectric layer consisting of an Ecoflex-coated self-healable polydimethylsiloxane (SH-PDMS) polymer that can autonomously repair mechanical injury at room temperature and regain its functionality. Different compositions of bis(3-aminopropyl)-terminated PDMS and 1,3,5-triformylbenzene were used to synthesize SH-PDMS films to determine the optimum healing time. The SH-PDMS films contain reversible imine bonds that break when the material is damaged and are subsequently restored by an autonomous healing process. However, the inherent stickiness of the SH-PDMS surface itself renders the material unsuitable for application in TENGs despite its attractive self-healing capability. We show that spin-coating a thin layer (≈32 μm) of Ecoflex on top of the SH-PDMS eliminates the stickiness issue while retaining the functionality of a triboelectric material. TENGs based on Ecoflex/SH-PDMS and nylon 6 films show excellent output and fatigue performance. Even after incisions were introduced at several locations in the Ecoflex/SH-PDMS film, the TENG spontaneously attained its original output performance after a period of 24 h of healing. This study presents a viable approach to enhancing the longevity of TENGs to harvest energy from continuous mechanical actions, paving the way for durable, self-healable mechanical energy harvesters.

Photofunctional gold nanocluster-based nanocomposite coating for enhancing anti-biofouling and anti-icing properties of flexible films

Elastomeric materials have garnered significant attention across biomedical and industrial fields. Multifunctionality and environmental stability are essential requirements for the application of these materials. Herein, we developed photofunctional gold nanocluster-based nanocomposites (SiO2-AuNC) and coated them on elastomeric polydimethylsiloxane (PDMS) films through one-step way to enhance anti-biofouling and anti-icing properties. The SiO2-AuNC coating, created by immobilizing ultra-small gold nanoclusters (AuNCs) onto hydrophobic silica nanoparticles surface using a gel-sol method, forms an island-like convex structure. The immobilization significantly enhanced radiative transitions and promoted the generation of reactive oxygen species of AuNCs, which provided robust anti-biofouling property through photosensitization to the films. Meanwhile, the rigid SiO2-AuNC nanocomposite markedly enhances the wear resistance of the films. Additionally, the hierarchical micro- and nanostructure of SiO2-AuNC coating increases the hydrophobicity of the films, effectively preventing the aggregation of supercooled water droplets, thereby providing superior and durably anti-icing properties. This one-step coating provides a simple and effective strategy for multifunctional surface modification with nanoparticles, showing potential biomedical and industrial applications.

High sensitivity gas pressure and temperature optical sensors based on tapered no-core fiber coated with polydimethylsiloxane (PDMS)

This article introduces a novel high-sensitivity pressure and temperature sensor utilizing a tapered no-core fiber (NCF) structure created by splicing the NCF with a single-mode fiber (SMF) to form a “SMF-NCF-SMF” structure, tapering the NCF, and applying a polydimethylsiloxane (PDMS) film on the tapered NCF surface. The experimental results show that the device with a diameter of 10 μm has a pressure sensitivity of 86.63 nm/MPa within one to two atmospheres. Furthermore, the temperature sensitivity is −1.97 nm/°C from 30 °C to 60 °C. The sensor exhibits excellent stability and repeatability, and the PDMS film enhances the mechanical strength of the device, indicating promising potential for high-sensitivity pressure and temperature applications.

Low detection limit of uric acid based on Prussian blue-enhanced photothermal effect with microfiber knot resonator

The human serum uric acid (UA) level is a crucial indicator for diagnosing dementia in middle-aged and elderly individuals, with decreased levels being expressed in patients. Therefore, developing a high-performance sensor for online uric acid detection is of significant research interest. Herein, a microfiber knot resonator (MKR) sensor for quantitative detection of UA levels is reported. Combining polydimethylsiloxane (PDMS) with an adiabatic MKR, the specificity of UA detection in serum is improved using the photothermal effect of Prussian blue-enhanced uricase reaction. During the sensor operation, UA generates the photothermal effect under 650 nm laser irradiation, causing the PDMS film to expand with heat absorption, thereby shifting the resonance spectrum of the PDMS-MKR sensor. Experimental results demonstrate a sensitivity of 0.0559 nm/(μmol/L) within a UA concentration range of 40–120 μmol/L and a detection limit as low as 0.3578 μmol/L. The proposed sensor shows potential applications in clinical point-of-care early diagnosis and prognosis of dementia due to its specificity, fast detection speed, robustness, and high integration.

A flexible high-precision photoacoustic retinal prosthesis.

Retinal degenerative diseases of photoreceptors are a leading cause of blindness with no effective treatment. Retinal prostheses seek to restore sight by stimulating remaining retinal cells. We here present a photoacoustic retinal stimulation technology. We designed a polydimethylsiloxane and carbon-based flexible film that converts near-infrared laser pulses into a localized acoustic field, aiming at high-precision acoustic activation of mechanosensitive retinal cells. This photoacoustic stimulation of wild-type and degenerated ex vivo retinae resulted in robust and localized retinal ganglion cell activation with sub-100-µm resolution in both wild-type and degenerated ex vivo retinae. Our millimeter-size photoacoustic film generated neural activation in vivo along the visual pathway to the superior colliculus, as measured by functional ultrasound imaging when the film was implanted in the rat subretinal space and stimulated by pulsed laser. Biosafety of the film was indicated by absence of short-term adverse effect under optical coherence tomography retinal imaging, while local thermal increase was measured below 1 °C. These findings demonstrate the potential of our photoacoustic stimulation for visual restoration in blind patients with a high spatial precision and a large field of view.

Mid-Infrared Photoacoustic Stimulation of Neurons through Vibrational Excitation in Polydimethylsiloxane.

Photoacoustic (PA) emitters are emerging ultrasound sources offering high spatial resolution and ease of miniaturization. Thus far, PA emitters rely on electronic transitions of absorbers embedded in an expansion matrix such as polydimethylsiloxane (PDMS). Here, it is shown that mid-infrared vibrational excitation of C─H bonds in a transparent PDMS film can lead to efficient mid-infrared photoacoustic conversion (MIPA). MIPA shows 37.5 times more efficient than the commonly used PA emitters based on carbon nanotubes embedded in PDMS. Successful neural stimulation through MIPA both in a wide field with a size up to a 100µm radius and in single-cell precision is achieved. Owing to the low heat conductivity of PDMS, less than a 0.5°C temperature increase is found on the surface of a PDMS film during successful neural stimulation, suggesting a non-thermal mechanism. MIPA emitters allow repetitive wide-field neural stimulation, opening up opportunities for high-throughput screening of mechano-sensitive ion channels and regulators.

Plasmonic Nanostructures Grown from Reacting Droplet-In-Microwell Array on Flexible Films for Quantitative Surface-Enhanced Raman Spectroscopy in Plant Wearable In Situ Detection.

Plant wearable detection has garnered significant interest in advancing agricultural intelligence and promoting sustainable food production amidst the challenges of climate change. Accurately monitoring plant health and agrochemical residue levels necessitates qualities such as precision, affordability, simplicity, and noninvasiveness. Here, a novel attachable plasmonic film is introduced and designed for on-site detection of agrochemical residues utilizing surface-enhanced Raman spectroscopy (SERS). By functionalizing a thin polydimethylsiloxane film with silver nanoparticles via controlled droplet reactions in micro-well arrays, a plasmonic film is achieved that not only maintains optical transparency for precise analyte localization but also conforms closely to the plant surface, facilitating highly sensitive SERS measurements. The reliability of this film enables accurate identification and quantification of individual compounds and their mixtures, boasting an ultra-low detection limit ranging from 10-16 to 10-13 m, with mini mal relative standard deviation. To showcase its potential, on-field detection of pesticide residues on fruit surfaces is conducted using a handheld Raman spectrometer. This advancement in fabricating plasmonic nanostructures on flexible films holds promise for expanding SERS applications beyond plant monitoring, including personalized health monitoring, point-of-care diagnosis, wearable devices for human-machine interface, and on-site monitoring of environmentalpollutants.

Suppression of dead zones in slot-coated organic thin films by monitoring of meniscus formation for OLEDs

There inevitably appear dead zones in organic thin films fabricated by sheet-to-sheet slot-die coating because a coating start varies and the recovery time of internal pressure in slot-die head differs for each coating, resulting in poor coating repeatability. Slot-coated thin films within dead zones are thinner or thicker, possibly causing non-uniform light emission from solution-processable organic light-emitting diodes (OLEDs). To tackle it, we have devised an automatic coating start method based on the monitoring of meniscus formation. It automatically starts coatings when the cross-sectional area of meniscus reaches a certain optimal value in such a way that the start of each coating is kept unchanged. It is found that high-viscosity (4800 cPs) polydimethylsiloxane (PDMS) requires a longer time for the internal pressure of slot-die head to reach a steady state than low-viscosity (80 cPs) poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS). It can be reduced to a great extent by applying a method of discharging the solution in advance (pre-discharging scheme). Compared with high-viscosity PDMS films, low-viscosity PEDOT:PSS films are shown to have longer dead zones and poorer repeatability due to the fact that the dead zone of relatively thin films varies sensitively to a small change in the coating start timing. With this scheme, we have successfully fabricated a highly uniform OLED device with no dead zones in the emission area.

A Highly Sensitive D-Shaped PCF-SPR Sensor for Refractive Index and Temperature Detection.

A novel highly sensitive D-shaped photonic crystal fiber-based surface plasmon resonance (PCF-SPR) sensor for dual parameters of refractive index and temperature detecting is proposed. A PCF cladding polishing provides a D-shape design with a gold (Au) film coating for refractive index (RI) sensing (Core 1) and a composite film of silver (Ag) and polydimethylsiloxane (PDMS) for temperature sensing (Core 2). Comsol Multiphysics 5.5 is used to design and simulate the proposed sensor by the finite element method (FEM). The proposed sensor numerically provides results with maximum wavelength sensitivities (WSs) of 51,200 and 56,700 nm/RIU for Core 1 and 2 as RI sensing while amplitude sensitivities are -98.9 and -147.6 RIU-1 with spectral resolution of 1.95 × 10-6 and 1.76 × 10-6 RIU, respectively. Notably, wavelength sensitivity of 17.4 nm/°C is obtained between -20 and -10 °C with resolution of 5.74 × 10-3 °C for Core 2 as temperature sensing. This sensor can efficiently work in the analyte and temperature ranges of 1.33-1.43 RI and -20-100 °C. Due to its high sensitivity and wide detection ranges, both in T and RI sensing, it is a promising candidate for a variety of applications, including chemical, medical, and environmental detection.

Broadband near-infrared mechanoluminescence in Cr3+ doped Mg3Ga2GeO8

Recently, in situ and real time near-infrared mechanoluminescence (NIR ML) materials are attracting increased attention, which has potential applications such as in biostress sensing. However, most of the NIR ML materials so far are limited to narrow band emission, making it challenging to meet the requirements for specific biological applications. In this study, a novel broadband NIR ML material of Mg3GaInGeO8: 0.04Cr3+ (FWHM (full width at half maxima) = 179.4 nm,) is obtained through multi-lattice occupation and lattice engineering strategies. The crystal field strength, time decay curve and Gaussian fitting analysis reveal that the varied FWHM are attributed to the three emission Cr3+ lattice site centers. Using In3+ ion to substitute Ga3+ ion lattice site, the NIR ML peak is red-shifted (786.1 → 803.5 nm), and the FWHM value is expanded (168.0 → 179.4 nm). NIR ML signal from Mg3Ga2GeO8:Cr3+/polydimethylsiloxane (PDMS) film can easily penetrate 10 mm thick pork tissue, which may find potential applications in biostress sensing.

Advanced Light Management for Encapsulated Silicon Solar Cells: An Antireflective Textured Film with a Down-Shifting Lead-free Perovskite Cs2AgxNa1-xBiyIn1-yCl6 Phosphor.

Light management (LM) is the key to the encapsulation of high-performance silicon (Si) photovoltaic devices (PVs). In this work, simulation analyses provide meaningful insights into optical losses and guide the improvement of the PV performance of the encapsulated silicon solar cells (Encap-Si SCs). An antireflective layer, textured polydimethylsiloxane (PDMS), is designed to reduce reflection losses, especially at a lower illumination intensity, thereby achieving an improvement of 10.89% in the short-current density (JSC) and hence 12.67% in the power conversion efficiency (PCE) when illuminated at an incident angle of 60°. Subsequently, a luminescence down-shifting material, lead-free Cs2AgxNa1-xBiyIn1-yCl6 (CANBIC) double perovskite phosphor, is incorporated into the PDMS film to further enhance the energy yield in the ultraviolet (UV) region. The textured PDMS film with an optimized CANBIC content ultimately achieves a significant improvement in PCE from 21.770 to 23.136%. This enhancement is attributed to the increase in JSC by 2.381 mA/cm2 due to the reduced reflection losses (by antireflective PDMS) and down-converted UV energy (by CANBIC), providing a remarkable advance in LM toward highly efficient encapsulated PVs.

Ladybug-inspired hierarchical composite adhesives for enhanced surface adaptability

Abstract Enhanced adhesion on rough surfaces is highly desired for a wide range of applications. On the other hand, surface roughness compatibility and structure stability are two critical but competing factors for biologically-inspired dry adhesives in the real world. Inspired by ladybug, a hierarchical structural composite dry adhesive (denoted as PP-M) with enhanced robustness on surface roughness is developed, which is composed of a thin compliant contact layer (a thin soft polydimethylsiloxane (PDMS) film supported discretely by PDMS micropillars) and a rigid bottom layer magnetorheological elastomers (MREs). The PP-M shows a high pull-off strength of 8.2 N cm−2 on a smooth surface and nano-scale rough surface at a mild preload (2 N cm−2). For micro-scale rough surfaces, the PP-M exhibits better surface adaptability compared to the double-layered adhesive (PDMS on MRE) without micropillar support. The increased compliance of the contact layer also leads to a 2.11 fold superior pull-off strength at a wider range of roughness (Sq &gt; 2.23 μm). Element analysis confirms PP-M’s enhanced adaptability, attributed to deeper indentation and lower contact stress. This hierarchical composite structure in PP-M, characterized by a ‘soft on top and hard on bottom’ stiffness distribution, synergizes the flexible contact layer with the stiff MRE bottom layer, leading to superior adhesive properties. The results provide a new reference for achieving enhanced adhesion on rough surfaces.

Fabrication of organic thin films using slit nozzle with a wide viscosity spectrum

A slit nozzle with a broad viscosity spectrum is highly demanded for slit coating of various materials with different viscosities without a compromise on the film quality. To this end, we have fabricated a multi-cavity slit nozzle with the inlet and vent holes for each cavity. Compared with a slit nozzle with a high-volume single cavity, such a multi-cavity slit nozzle further reduces the dead volume and thus material waste. As a design parameter in computational fluid dynamics (CFD) simulations for the multi-cavity slit nozzles, we have calculated the coefficient of variation in the internal pressure (Pcv) of the cavity and investigated the correlation between the simulated Pcv value and the measured thickness uniformity of low-viscosity (tens of cPs) poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), medium-viscosity (5000 cPs) polydimethylsiloxane (PDMS), and high-viscosity (18,000 cPs) hard-PDMS films. It is addressed that the Pcv value that can ensure the thickness non-uniformity of less than 5 % is of the order of 1 %, and the internal pressure of the nozzle should not exceed a specific upper limit to protect a coating system against overload. Based on the design guideline provided, we have found that the upper limit of the viscosity spectrum of the triple-cavity slit nozzle with the 800-μm-thick shim is 79,000 cPs when the flow rate is 50 ml/min. Using the multi-cavity slit nozzle, we have fabricated a highly uniform PDMS film exhibiting the tensile strain as high as 180 %, which can be used as a substrate for stretchable displays. Furthermore, we have successfully fabricated flexible OLED stripes on the slit-coated conductive PEDOT:PSS stripes, showing the average luminance of 72.8 cd/m2 at 5 V and inter-stripe luminance non-uniformity as low as 8.2 %.