Polymer Patterns Research Articles

Metasurface color filter arrays with a high efficiency and low color error

Conventional digital cameras combine absorbing color filter arrays with microlenses to achieve color imaging and improve efficiency. Such cameras require multi-step and multi-material fabrication processes. Several recent efforts have investigated metasurface-based color routing to combine focusing with filtering in a single functional layer with an improved efficiency. These approaches require high-refractive index materials and deep sub-micron fabrication to realize the metasurfaces. We present here an alternative, 2.5 dimensional metasurface that simultaneously provides both color filtering and focusing, but requires only a low-refractive index polymer and micron-scale patterning such that it is suitable for replication by molding. Unlike Bayer filters, this metasurface produces six independent spectra focused on nine monochrome pixels yielding both a high efficiency and low color error. These metasurfaces could be more photo-stable and thermally stable than dye-based filters and less expensive to produce than conventional arrays or metasurface color routers. Here, we characterize a metasurface-based focusing color filter array prototyped using two-photon lithography whose efficiencies are competitive with Bayer filters and whose color error is comparable to the limit of human perception.

High-Resolution Electrohydrodynamic Printing with Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) Conductive Polymers

Conductive polymer materials, particularly PEDOT:PSS conductive polymers, have gained widespread attention due to their excellent conductivity, processability, and biocompatibility, making them highly applicable in fields such as bioelectrodes, flexible sensors, and soft robotics. With the rapid development of flexible electronics, the demand for micron-scale precision in the processing of conductive polymers grows. However, advanced fabrication techniques, such as 3D printing and screen printing, which are currently popular in research, face challenges in achieving a micron-level resolution, limiting the further application of conductive polymers. In this study, we demonstrate three types of PEDOT:PSS inks and systematically explore their suitability for electrohydrodynamic (EHD) jet printing. We investigate the impact of critical parameters, including voltage, printing speed, and printing height, on the accuracy of printed patterns. Among the formulations, the optimized PEDOT:PSS to ethylene glycol ratio of 1:1 achieves line widths of 20 µm. Based on this ink, we successfully print flexible conductive polymer patterns with line widths ranging from 20 µm to 90 µm and fabricate PEDOT:PSS conductive films with dimensions of 1.5 cm × 0.5 cm. This high-precision PEDOT:PSS ink demonstrates a strong potential for applications in high-density electrode arrays, electrochemical transistors, and brain–machine interfaces, paving the way for advanced flexible electronics.

Predicting Precursor Ions Combined with Fragmentation Pathway for Screening and Identification of Flavan-3-ol Oligomers in Tea (Camellia sinensis. var. assamica).

Flavan-3-ol oligomers (FLOs), including proanthocyanidins (PAs) and theasinensins (TSs), contribute greatly to the flavor and bioactivity of the tea beverage. Ultrahigh-performance liquid chromatography coupled with high-resolution mass spectrometry has been widely used in profiling a wide range of compounds in tea. However, the detection and identification of FLOs with low concentration and high structural diversity remain meaningful yet challenging work. Herein, we propose a strategy that enables efficient discovery and annotation of FLOs, especially those with a relatively high degree of polymerization (DP, ≥3). Based on the known monomers and the specific polymerization pattern between them, the strategy predicted a theoretical list of precursor ions of FLO. Matching the predicted list against the experimental ion features screened out 490 features as the candidate of FLOs from over 10 000 raw features. Investigation of the fragmentation pathways of 17 known FLOs found that both PAs and TSs are easily subjected to RDA cleavage, which produced a series of characteristic fragmentation ions and neutral losses. Moreover, successive cleavage of the C4 → C8 bond between monomer units is observed for PAs, leading to the generation of characteristic fragmentation ions corresponding to monomeric flavan-3-ols. Assisted by the characteristic fragmentation pathways, 52 FLOs (DP: 2-6) were finally annotated from the 490 retained features. Their chemical structures were verified by depolymerization experiments using menthofuran as the nucleophilic trapping reagent. Among them, the pentamers and hexamers were detected in a Yunnan large leaf tea for the first time. Semiquantitation and multivariate statistical analysis indicate that PAs exhibit higher contents in green tea, and TSs show higher levels in black and white tea.

Paralogous Gene Recruitment in Multiple Families Constitutes Genetic Architecture and Robustness of Pod Dehiscence in Legumes.

Pod dehiscence facilitates seed dispersal in wild legumes while indehiscence is a key domestication trait in cultivated ones. However, the evolutionary genetic mechanisms underlying its diversity are largely unclear. In this study, we compared transcriptomes of two warm-season (Glycine spp. and Phaseolus spp.) and two cool-season (Pisum spp. and Medicago ruthenica) legumes in analysis of dehiscent and indehiscent pod genotypes. Differentially expressed genes in AP2/ERF-like transcription factors and seven structural gene families, including lactoperoxidase, laccase, and cellulose synthase-interactive proteins, which are involved in secondary cell wall component accumulation, were identified to exert key roles in pod dehiscence variation. In accordance with this, higher lignin and cellulose contents were observed in pod secondary cell wall of dehiscent accessions of soybean and pea; however, the variation patterns of lignin polymers in soybean (accumulation) and pea (proportion) differed between dehiscent and indehiscent pods. Moreover, genome-wide comparative analysis revealed that orthogroups represented <1% of all identified differentially expressed genes could be traced among the four genera of legumes, while recruiting paralogous members may constitute the genetic robustness of legume pod dehiscence. This study compared the genetic mechanism among several legumes in pod dehiscence formation and revealed a compensating role of paralogous redundancy of involved gene families in seed dispersal, which can guide crop breeding.

Numerical Response of Concrete-Filled Steel Tubular (CFST) Columns Externally Strengthened with FRP Composites Subjected to Cyclic Loading

The ultimate load-carrying capacity of concrete-filled steel tubular (CFST) columns exposed to monotonic loadings can be greatly increased by strengthening those columns, and the occurrence of the steel tube's outward buckling can be postponed. The current research aims to study the possibility of improving the structural characteristics of CFST columns exposed to cyclic loadings in terms of lateral load capacity and absorbed energy by strengthening them with different patterns of fiber-reinforced polymer (FRP) sheets. The ABAQUS software was used to create a three-dimensional (3D) non-linear finite element model (FEM) to simulate the behavior of FRP-strengthened CFST columns exposed to monotonic and cyclic loadings. After ascertaining the accuracy of the proposed model's results in successfully predicting failure patterns and lateral loads compared to the experimental results of tested specimens available in the literature, the model was used to create a parametric study. The parametric study focused on the impacts of the thickness, location, and length of the strengthening sheets on the failure pattern, lateral load-carrying capacity, stiffness, cumulative energy, absorbed energy, and viscous damping factor of the CFST columns exposed to cyclic loadings. The results revealed that the un-strengthened specimen displayed a maximum lateral load of 185 kN and a viscous damping factor of 45.2% at a lateral drift of 5.7%. On the other hand, strengthening the CFST column using five layers of FRP sheets exhibited the highest lateral load of all investigated columns (50% more than the un-strengthened specimen). Additionally, at a lateral drift of 5.7%, the decrease in viscous damping factor of CFST specimens due to strengthening using 1, 2, 3, 4, and 5 layers of FRP sheets with respect to the control specimen was 7.9%, 14.9%, 20.8%, 27.7%, and 30.3%, respectively.

Nanoimprinted Polymeric Structured Surfaces for Facilitating Biofilm Formation of Beneficial Bacteria

Initial studies indicate that structured polymer surfaces can support the attachment and biofilm formation of bacteria and thereby provide enhanced positive effects of beneficial bacteria, for instance in biocontrol in aquacultures. In this study, we demonstrate a test platform to further explore the surface topography for bacterial attachment and biofilm growth. It is based on a cyclic olefin copolymer (COC) materials platform, and nanoimprint technology was used for the replication of microstructures. The use of nanoimprint technology ensures precise micropattern transfer, enabling easy prototyping. Further, the process parameters of the mold preparation and nanoimprinting are discussed, with the purpose of optimizing the polymer pattern profile. This study has the potential to identify promising surfaces for biofilm growth of beneficial bacteria.

Ordered Transfer from 3D-Oriented MOF Superstructures to Polymeric Films and Patterns

Three-dimensional oriented metal-organic frameworks, or 3D-oriented MOFs, feature precisely arranged pores that extend over large areas. This order is essential for enhancing directed diffusion and arranging functional guest species within the oriented pore channels. [1] For example, pore orientation in porous MOF matrices is desired for photonics and ion conductivity uses.[2] Yet, 3D-oriented MOF films and patterns can rapidly decompose in the presence of moisture and acidic environments. [3] This propensity to degradation limits their applicability.Here, by starting with MOF films that are N3-functionalized and heteroepitaxially aligned, we promote the formation of an oriented polymeric film. With X-ray lithography, we target the azide groups for selective degradation thus enabling the crosslink in defined regions: this fabrication process enables the preparation of porous polymeric patterns. The water-stable porous polymer patterns showed unique fluorescent behaviour when exposed to polarized light, which holds promise for advancing optical and photonic devices. [4] References [1] M. Linares‐Moreau, L. A Brandner, M. de J Velásquez‐Hernández, J. Fonseca, Y. Benseghir, J.M. Chin, D. Maspoch, C. Doonan, P. Falcaro Adv.Mater. 2024, 36, 2309645[2] M.d.J. Velásquez-Hernández, M. Linares-Moreau, L.A. Brandner, B. Marmiroli, M. Barella, G.P. Acuna, S.D, Zilio, M.F.K. Verstreken, D.E. Kravchenko, O.M. Linder-Patton, J.D. Evans, H. Wiltsche, F. Carraro, H. Wolinski, R. Ameloot, C. Doonan and P. Falcaro. Adv.Mater. 2023, 35, 2211478.[3] L.A Brandner, M. Linares-Moreau, G. Zhou, H. Amenitsch, S. Dal Zilio, Z. Huang, C. Doonan, P. Falcaro Chem.Sci., 2023, 14, 12056.[4] L.A. Brandner, B. Marmiroli, M. Linares-Moreau, M. Barella, B. Abbasgholi-NA, M.de J. Velásquez-Hernández, K. L. Flint, S.Dal Zilio, G. P. Acuna, H. Wolinski, C. J. Doonan, P. Falcaro, Submitted.

The influence of myrcene on anionic copolymerization of 1,3-pentadiene and styrene

C5-dienes including 1,3-pentadiene (PD) and isoprene (IP) as by-products of naphtha cracking are important industrial raw materials for the production of thermoplastic elastomers, synthetic rubber and resins. The research on living anionic polymerization (LAP) of myrcene (MY) is also of great significance for the development of new bio-based materials and products. Focusing on the optimal utilization of C5 resources and the high-value utilization of biomass resources and the realization of green chemical production, this article reports the synthesizing of a novel terpolymer by LAP of PD, styrene (ST) and the biomass monomer MY. The discovery of the alternating sequence structure of ST and PD inspires us to further explore the development of copolymers containing this unique sequence structure. The special long branched side chain of MY and its low glass transition temperature are also conducive to the synthesis of new integrated rubbers. The 1H NMR tracking analysis indicates that the polymerization pattern changes from alternating sequence to gradient block sequence with the increase of MY content. Combined with FTIR analysis, the PD monomeric units are mainly trans-1,4 structure and MY monomeric units are predominant cis-1,4 structure. Considering the extremely high polymerization activity of MY compared to ST and PD, the copolymerization rate is significantly dependent on the concentration of the PD monomer. Despite this, due to the interactions between ST and PD ([ST¦PD] intermediate), ST still tends to form alternating segments with PD. The ternary copolymerization can be viewed as a “binary gradient copolymerization” of [ST¦PD] and MY (rMY > r[ST¦PD]).

Omniphobic Photoresist‐Assisted Patterning of Porous Polymethacrylate Films

AbstractPatterning of various surface properties, including roughness, wettability, adhesiveness, and mechanical properties, can markedly enhance the functionality of test systems. Thus, porous polymethacrylates prepared by polymerization‐induced phase separation (PIPS) represent a promising class of functional materials for the construction of miniaturized test systems. Different porosity, surface chemistry, and wettability are achieved in porous polymethacrylates with different precursor compositions. Nevertheless, only wettability microstructuring has been highlighted for these materials thus far. Here, the study presents a novel method for the direct and selective deposition of porous polymethacrylate films with different surface chemistry and porosity. The selective adhesion of omniphobic–omniphilic wettability patterns is used to facilitate the polymer pattern formation. The feasibility of patterning with different monomers and porogenic solvents is demonstrated. The topological study confirms the selective application of polymer structures with different thickness and roughness. The wettability characterization of the omniphobic material shows no significant changes caused by the operations performed. Thus, a new pattern with a greater difference in the wettability of the areas is produced in the process. Discontinuous dewetting of different liquids is performed. The use of poly(2‐hydroxyethyl methacrylate‐co‐ethylene dimethacrylate) (HEMA‐EDMA) modified patterns for precise living cell patterning is also demonstrated.

Synergistically flexible-robust effects mediate the dynamic reconfiguration of perylene diimide polymer to enhance piezo-photocatalytic nitrate reduction

Identifying the spatial dynamic reconstruction of π-conjugated polymers for efficient carrier transport and controlling the intermediate process of the reaction are urgent and formidable challenges. In this study, a fresh perspective has emerged proposing to synergistically enhance the adaptability and resilience of dynamic torsion patterns in π-conjugated polymers to mediate charge separation and molecular activation. Excitingly, the highest flexible-robust structure and polarity of naphthalene-linked perylene diimide polymer (N-PDA) demonstrates a highest nitrate reduction rate of 5.36 mmol g−1 h−1 under light irradiation and ultrasonic condition, which is 7.5 times that of H-PDA. Theoretical calculations and experimental observations indicate that the strongest flexible-robust structure of N-PDA enhances the inclination of the rigid plane and atomic bond length, resulting in an accelerated uneven distribution of charges, molecular polarity, and electronic coupling to facilitate charge separation dynamics. Moreover, it exposes active sites that promote the adsorption and activation of NO3- ions while simultaneously regulating intermediate hydrogenation processes. Our study offers innovative prospects for enhancing catalytic efficiency through the implementation of spatial steric configuration of π-conjugated polymers.

Patterning damage mechanisms for two-dimensional crystalline polymers and evaluation for a conjugated imine-based polymer

High-quality patterning determines the properties of patterned emerging two-dimensional (2D) conjugated polymers and is essential for potential applications in future electronic nanodevices. However, the most suitable patterning method for 2D polymers has yet to be determined because we still do not have a comprehensive understanding of their damage mechanisms by visualizing the structural modification that occurs during the patterning process. Here, the damage mechanisms during patterning of 2D polymers, induced by various patterning methods, are unveiled based on a systematic study of structural damage and edge morphology in an imine-based 2D polymer (polyimine). Patterning using a focused electron beam, focused ion beam (FIB) and mechanical carving is evaluated. The focused electron beam successively introduces a sputtering effect, knock-on displacement damage and massive radiolysis with increasing electron dose from9.46×107electrons nm-2to1.14×1010electrons nm-2. Successful patterning is enabled by knock-on damage but impeded by carbon contamination beyond a critical sample thickness. A FIB creates current-dependent edge morphologies and extensive damage from ion implantation caused by the tail of the unfocused beam. A precisely controlled tip can tear the polyimine film through grain boundaries and hence create a patterning edge with suitable edge roughness for certain application scenarios when beam damage is avoided. Taking structural damage and the resulting quantitative edge roughness into consideration, this study provides a detailed instruction on the proper patterning techniques for 2D crystalline polymers and paves the way for tailored intrinsic properties and device fabrication using these novel materials.

Poly(ethylene glycol) patterned surfaces functionalized with gallic acid@Au nanoparticles: investigation of antibacterial activity for biomedical applications

Polymer patterns are promising for many applications due to their high stability and superior chemical and physical properties. By functionalizing various surfaces with polymer patterns, it is possible to detect and prevent many common infections. Treatment of resistant bacteria with antibiotics is limited and they can spread quickly. For this reason, it was designed a surface that can prevent contamination by functionalizing polymer patterns. In the study, a polymer pattern model obtained by combining gallic acid with gold nanoparticles (GA@AuNP) synthesized through green chemistry was designed. Polymer-patterned structures were obtained on silicon wafers using Poly(ethylene glycol) (PEG) polymer and were self-assembled with GA@AuNPs. Diagnosis and inhibition of bacterial cells in a short time were demonstrated with the prepared modified PEG polymer pattern. Surface-enhanced Raman scattering effects were used to optimize the stability of surfaces patterned with self-assembled GA@Au NPs. By modification of PEG polymer patterns, a biomarker design that can be used in many different bioapplications is proposed.

The structure and interaction of polymers affects secondary cell wall banding patterns in Arabidopsis.

Xylem tracheary elements (TEs) synthesize patterned secondary cell walls (SCWs) to reinforce against the negative pressure of water transport. VASCULAR-RELATED NAC-DOMAIN 7 (VND7) induces differentiation, accompanied by cellulose, xylan, and lignin deposition into banded domains. To investigate the effect of polymer biosynthesis mutations on SCW patterning, we developed a method to induce tracheary element transdifferentiation of isolated protoplasts, by transient transformation with VND7. Our data showed that proper xylan elongation is necessary for distinct cellulose bands, cellulose-xylan interactions are essential for coincident polymer patterns, and cellulose deposition is needed to override the intracellular organization that yields unique xylan patterns. These data indicate that a properly assembled cell wall network acts as a scaffold to direct polymer deposition into distinctly banded domains. We describe the transdifferentiation of protoplasts into TEs, providing an avenue to study patterned SCW biosynthesis in a tissue-free environment and in various mutant backgrounds.

Facile one-pot synthesis and characterization of ZnSe/HPMC nanocomposites

Herein, we report the facile synthesis of ZnSe/HPMC (Hydroxypropyl Methyl Cellulose) nanocomposites by in-situ method. The biodegradable HPMC polymer acts as capping molecule as well as polymer matrix. The optical and structural properties of ZnSe/HPMC nanocomposites were studied by optical absorption, photoluminescence (PL) spectroscopy, FTIR, XRD and TEM measurements. Size of the ZnSe nanoparticles was tuned by controlling the pH of the reaction. As prepared ZnSe nanoparticles were spherical in shape, homogeneously distributed in the polymer and XRD patterns exhibit face centred cubic phase. The present method is a novel approach for the synthesis of ZnSe nanoparticles using HPMC as a capping molecule as well as matrix to develop nanocomposite.

Multi-modal flexible and inexpensive plasmonic metasurface for wide range of refractive index sensing

Abstract A plasmonic metasurface containing nanobumps of sub-wavelength feature size arranged in a hexagonal pattern on a flexible substrate and covered with a thin film of gold is investigated as a refractive index sensor. The chosen polymer patterns coated with gold aid in activating the surface plasmon polariton modes. Using numerical calculations, it is shown that this surface can exhibit plasmonic effect with an extremely shallow pattern height of 92.5 nm and minimal thickness of 25 nm of gold over it. The excitation of the plasmonic modes is confirmed using electric field profiles calculated at the relevant wavelengths. As the surface is highly sensitive to changes in the cladding index, and the chosen design aids in exciting three plasmon modes that are suitably well-separated in wavelength, this surface can be used for an extremely wide range of refractive index sensing because each mode contributes uniquely to a different range of refractive index. The results establish that the metasurface is suitable for a variety of applications, including gas detection with a sensitivity of 633 nm/RIU using mode-1, identifying SARS-CoV-2 viral molecules with a sensitivity of 428 nm/RIU using mode-2 and 238 nm/RIU using mode-3, and discriminating between normal and diseased brain tissues in the cerebrospinal fluid in the high-index range using mode-3. The prototype metasurface is made using a cost-effective soft lithography technique using an economical master mould. The inexpensive technique of fabrication, use of very thin metal film, and wavelength of detection lying within the visible to near infrared range imply a low-cost sensor. The structural and optical characterization of the prototype validates the numerical study of the sample.

Electrohydrodynamic Printing of Biodegradable PLGA Micro‐Patterns on 3D Polymer Structures

AbstractBiodegradable polymers such as polylactic‐co‐glycolic acids (PLGA) are used for various implantable devices such as tissue scaffolds, drug delivery devices, and biosensors in different forms. However, high‐resolution patterning of biodegradable polymers on implantable devices has not been explored much yet. While electrohydrodynamic printing (EHD) can achieve high‐resolution printing compared to other printing methods, EHD printing of PLGA solutions is rarely attempted due to unstable printing. Such printing instability originates from the volatile nature of PLGA inks, and it causes nozzle clogging or change of ink conditions during printing. Here, PLGA ink formulation and a voltage input profile are studied for stable and high‐resolution EHD printing. Addition of glycerol at an optimal ratio as well as the control of voltage pulse shape strongly influenced both the stability and resolution of EHD printing of PLGA patterns. With the optimized inks and voltage inputs, stable printing of PLGA micropatterns down to 5 µm is achieved on both conductive and insulating surfaces for controlled drug release. Furthermore, use of a ring type electrode allows for EHD printing of PLGA micropatterns on 3D surfaces of PLLA tubes and stent struts.

Ordered Transfer from 3D-Oriented MOF Superstructures to Polymeric Films: Microfabrication, Enhanced Chemical Stability, and Anisotropic Fluorescent Patterns.

Films and patterns of 3D-oriented metal-organic frameworks (MOFs) afford well-ordered pore structures extending across centimeter-scale areas. These macroscopic domains of aligned pores are pivotal to enhance diffusion along specific pathways and orient functional guests. The anisotropic properties emerging from this alignment are beneficial for applications in ion conductivity and photonics. However, the structure of 3D-oriented MOF films and patterns can rapidly degrade under humid and acidic conditions. Thus, more durable 3D-ordered porous systems are desired for practical applications. Here, oriented porous polymer films and patterns are prepared by using heteroepitaxially oriented N3-functionalized MOF films as precursor materials. The film fabrication protocol utilizes an azide-alkyne cycloaddition on the Cu2(AzBPDC)2DABCO MOF. The micropatterning protocol exploits the X-ray sensitivity of azide groups in Cu2(AzBPDC)2DABCO, enabling selective degradation in the irradiated areas. The masked regions of the MOF film retain their N3-functionality, allowing for subsequent cross-linking through azide-alkyne coupling. Subsequent acidic treatment removes the Cu ions from the MOF, yielding porous polymer micro-patterns. The polymer has high chemical stability and shows an anisotropic fluorescent response. The use of 3D-oriented MOF systems as precursors for the fabrication of oriented porous polymers will facilitate the progress of optical components for photonic applications.

Decoding thermal properties in polymer-inorganic heat dissipators: a data-driven approach using pyrolysis mass spectrometry

ABSTRACT Polymeric materials can boost their performances by strategically incorporating inorganic substances. Heat dissipators are a representative class of such composite materials, where inorganic fillers and matrix polymers contribute to high thermal conductivity and strong adhesion, respectively, resulting in excellent heat dissipation performance. However, due to the complex interaction between fillers and polymers, even slight differences in structural parameters, e.g. dispersion/aggregation degree of fillers and crosslink density of polymers, may significantly impact material performance, complicating the quality management and guidelines for material developments. Therefore, we introduce pyrolysis mass spectra (MS) as material descriptors. On the basis of these spectra, we construct prediction models using a data-driven approach, specifically focusing on thermal conductivity and adhesion, which are key indicators for heat dissipating performance. Pyrolysis-MS observes thermally decomposable polymers, which occupy only 0.1 volume fraction of the heat dissipators; nevertheless, the physical states of non-decomposable inorganic fillers are implicitly reflected in the pyrolyzed fragment patterns of the matrix polymers. Consequently, pyrolysis-MS provides sufficient information to construct accurate models for predicting heat dissipation performance, simplifying quality management by substituting time-consuming performance evaluations with rapid pyrolysis-MS measurements. Furthermore, we elucidate that higher crosslinking density of the matrix polymers enhances thermal conductivity. This data-driven method promises to streamline the identification of key functional factors in complex composite materials.

New Application of Multiresonance Organic Delayed Fluorescence Dyes: High-Performance Photoinitiating Systems for Acrylate and Epoxy Photopolymerization and Photoluminescent Pattern Preparation.

The primary focus of photopolymerization research is to advance highly efficient visible photoinitiating systems (PISs) as alternatives to conventional ultraviolet (UV) photoinitiators. We developed four multiresonance emitters (BIC-pCz, BNO1, BO-DICz, and TPABO-DICz) to sensitize iodonium salt (Iod) and initiate free-radical and cationic photopolymerization under visible light for the first time. The TPABO-DICz/Iod system achieved a double-bond conversion of over 70% within just 4 s of exposure to green light (520 nm), while the BNO1/Iod system achieved a double-bond conversion exceeding 50% with 10 s of exposure to red light (630 nm). The photochemical properties were studied through thermodynamic research, steady-state photolysis, and electron spin resonance. Photolithography techniques were employed to fabricate photoluminescent films and micrometer-scale patterns utilizing the blue-emitting BIC-pCz dye, showcasing the potential of photolithography in the production of photoluminescent pixels. Additionally, the BIC-pCz/Iod and TPABO-DICz/Iod systems have been employed to rapidly fabricate photoluminescent polymer patterns using a digital-light-processing 3D printer with a low-intensity light (3.2 mW cm-2). These multiresonance emitters show exceptional photosensitizing effects and can act as fluorescent dyes in photoluminescent patterns, highlighting the potential of utilizing photopolymerization for OLED applications.

Patterning of COC Polymers by Middle‐Energy Ion Beams for Selective Cell Adhesion in Microfluidic Devices

AbstractMicrofluidic devices play a crucial role in advanced cell biology applications, including cell separations, cultivations, migration and interaction studies, diagnostic devices, and organ‐on‐chips. One of the frequent purposes of such devices is the ability to selectively address the attachment of cells at defined locations on the surface. This study explores the application of middle‐energy carbon, oxygen, and nitrogen ions to locally modify the surface of cyclic olefin copolymer (COC) thermoplastic material, allowing selective cell growth on patterned polymer surfaces. The investigation considers ion element type, ion beam energy, and ion irradiation fluence, analyzing their influence on the modification effect. Characterization of the modified surfaces involves various surface‐analytical methods such as contact angle, energy dispersive spectroscopy (SEM‐EDX), atomic force microscopy (AFM), x‐ray photoelectron spectroscopy (XPS), rutherford backscattering spectrometry (RBS), and elastic recoil detection analysis (ERDA). The study extends to practical aspects, with a representative cancer cell line, MCF‐7, grown on the patterned surface to evaluate the degree of selective attachment. Additionally, the stability of the irradiated patterns is tested under elevated temperatures beyond the glass transition temperature (Tg), demonstrating the compatibility of the approach with hot embossing technology. The findings underscore the potential of ion beam treatment for COC in cell‐biology‐related applications, offering insights into surface modification techniques for enhanced functionality in microfluidic devices.