Functional Micro Research Articles

Femtosecond laser processing of amorphous silicon films

Femtosecond laser micromachining is a pivotal approach within the dynamic field of laser surface structuring, offering unparalleled precision for materials processing. By exploiting the unique nonlinear light-matter interactions, this technique allows the creation of functional micro- and nanostructures with exceptional accuracy and reproducibility. Of particular interest is its ability to process diverse materials, including glasses, polymers, metals, and semiconductors, with minimal thermal impact and collateral damage. Moreover, femtosecond laser micromachining eliminates the need for traditional lithographic methods, enabling intricate structure fabrication under ambient conditions, thereby revolutionizing microfabrication techniques. This study demonstrates the micromachining using femtosecond lasers at 800 nm wavelength and explores the critical role of process parameters, such as laser pulse energy and the number of pulses in determining the damage threshold fluence, especially considering incubation effects in multi-pulse scenarios. Furthermore, it explores the potential of femtosecond laser micromachining for controlled crystallization in hydrogenated amorphous silicon (a-Si:H), unleashing enhanced electrical and optical properties. With its versatility, precision, and potential for diverse applications, femtosecond laser micromachining holds promise for driving advancements in electronic and photonic devices, particularly in high-efficiency photovoltaics, integrated photonics, and novel optoelectronic technologies.

Discovery of Living Optical Networks in Orchid Leaves as Inspiration for Light Harvesting and Redistribution in Soft, Curvilinear Material Formats

AbstractPlants and animals produce highly evolved, hierarchical systems that combine physicochemical material parameters with functional micro‐ and nanostructures to manage energy, motion, and species survival. These systems, besides providing cues on bottom‐up manufacturing of technological structures, can give insight on strategies for efficient energy management. Here is reported the observation of an optically interconnected network formed by the cells of the leaves of the Macodes petola jewel orchid that provides light harvesting and redistribution across its surface. The planar redistribution of light incident on the leaf is enabled by the distinctively rounded shape of the outer epidermal cells and by their arrangement in a short‐range ordered hexagonal lattice. Successful replication of a live leaf in a free‐standing biopolymer film validates the observation and opens avenues for the exploration of non‐traditional energy harvesting interfaces that are soft, conformal, and curvilinear.

Effect of Carbon Nanotubes on Chloride Diffusion, Strength, and Microstructure of Ultra-High Performance Concrete.

This study delved into the integration of carbon nanotubes (CNTs) in Ultra-High Performance Concrete (UHPC), exploring aspects such as mechanical properties, microstructure analysis, accelerated chloride penetration, and life service prediction. A dispersed CNT solution (0.025 to 0.075 wt%) was employed, along with a superplasticizer, to ensure high flowability in the UHPC slurry. In addition, the combination of high-strength functional artificial lightweight aggregate (ALA) and micro hollow spheres (MHS) was utilized as a replacement for fine aggregate to not only reduce the weight of the concrete but also to increase its mechanical performance. Experimental findings unveiled that an increased concentration of CNT in CNT1 (0.025%) and CNT2 (0.05%) blends led to a marginal improvement in compressive strength compared to the control mix. Conversely, the CNT3 (0.075%) mixture exhibited a reduction in compressive strength with a rising CNT content as an admixture. SEM analysis depicted that the heightened concentration of CNTs as an admixture induced the formation of nanoscale bridges within the concrete matrix. Ponding test results indicated that, for all samples, the effective chloride transport coefficient remained below the standard limitation of 1.00 × 10-12 m2/s, signifying acceptable performance in the ponding test for all samples. The life service prediction outcomes affirmed that, across various environmental scenarios, CNT1 and CNT2 mixtures consistently demonstrated superior performance compared to all other mixtures.

Precision-controlled synthesis of monodisperse starch nanoparticles: Factors affecting the self-assembly kinetics

Enzymatic modification has emerged as a crucial technique for enhancing the physicochemical attributes of starch. In particular, the short-chain glucans (SCGs) obtained from the debranching of native starch has been utilized to produce functional micro- and nano-structures through their inherent self-assembly property. However, a significant challenge remains in controlling the self-assembly kinetics of SCGs, which often results in undesirable heterogeneous structures. This study explores the factors governing SCG self-assembly and their impact on the formation of monodisperse starch nanoparticles (SNPs). We discovered that incomplete removal of the debranching enzyme during SCG self-assembly leads to particle aggregation, with the degree of aggregation dependent on the concentration of remaining enzyme. Furthermore, the initial SCG concentration significantly influences SNP growth; high concentration results in gel-like structures, while lower concentration produces discrete and spherical nanoparticles. Complete dispersion of growth species, SCGs, before self-assembly through appropriate high-temperature heating was found to be critical for uniform nuclei formation, thereby resulting in the production of well-defined nanoparticles. Systematically manipulating these kinetic factors allowed us to fabricate monodisperse SNPs with an average size of 200 nm. This study advances our understanding of SCG self-assembly kinetics, providing valuable insights for the precision-controlled synthesis of starch-based nanoparticles.

Abstract 3726: Absence of synergistic effects for PARPi and immunotherapy combinations in ex vivo 3D micro tumor assay for ovarian cancer patients

Abstract Introduction: 50% of ovarian cancers are homologous recombination deficient (HRD), with 15% of the patients carrying a BRCA mutation. PARP inhibitors (PARPi) are designed to improve survival in HRD patients, but clinical responses to PARPi often do not match HRD status. In this study, a 3D ex vivo tumor testing platform was applied to quantify patient-specific drug responses to (combinations of) PARPi, chemo- and immunotherapies. Material and Methods: 81 patients with ovarian cancer eligible for chemotherapy were included in the trial between 2019 and 2022 in the Netherlands (IRB P18.032). Tumor clusters were isolated from ascites and solid tissue, seeded and exposed to three PARPi, standard-of-care chemotherapies and immunotherapies, both single agent and in combination. Ex vivo drug sensitivity was quantified using high-throughput 3D imaging and extraction of morphological features. Bliss scores were calculated for synergy analysis. Results: Results were generated in two weeks after sample collection. Ex vivo patient-specific response profiles were observed for all drug classes, with a small percentage of patients (7%) showing strong PARPi sensitivity reflected by strong tumor cluster shrinkage upon treatment. Significant correlation of drug sensitivity profiles was observed comparing the different PARPi between themselves, but also comparing PARPi and platinum responses. Interestingly, ex vivo sensitivity to olaparib and immunotherapy combinations demonstrated additive, but no synergistic effects (21 patients, 79 tests). In addition, olaparib responses were shown to be independent of immune responses (SEA). Conclusion: This study applied a predictive ex vivo 3D micro tumor testing platform to classify patient-specific sensitivity to (a combination of) PARPi, chemo- and immunotherapies in over 80 patients. The current dataset demonstrates the potential of ex vivo testing to identify patients that are responsive to PARPi. No synergistic effects were observed for these drugs in combination with immunotherapies. Discussion: Evaluation of PARPi responses in a functional 3D micro tumor assay could support identification of responsive patients prior to treatment. Distinct responses were observed for PARPi and immunotherapies. No synergistic but additive effects were measured, suggesting that ovarian cancer patients could benefit from PARPi and immunotherapies. Correlation of clinical and ex vivo drug responses to PARPi in combination with available HRD tests will further validate the platform for predicting patient clinical outcome. Citation Format: Lieke J. Ceton, Esmee Koedoot, Timothy J. Sijsenaar, Dieudonné J. van der Meer, Marta Montero Garcia, Jurrian van der Valk, Kristofer Maad, Cor de Kroon, Anne van Altena, Willemijn Vader, Judith Kroep, Nelleke Ottevanger. Absence of synergistic effects for PARPi and immunotherapy combinations in ex vivo 3D micro tumor assay for ovarian cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3726.

Optical functionality simulation through traceable characterization of optical components

The production of high-value components containing functional micro- and submicron-scale features requires the implementation of high-quality in-process inspection technologies to guarantee zero-defect manufacturing, boosting the transition to digital manufacturing. In the present study, the impact of the measurement uncertainty assigned to surface micro- and submicron-structures on the optical performance of a one-dimensional diffraction grating was determined. Thus, 3D confocal microscopy was selected as an inspection technology, introducing measuring data and uncertainty values on an optical simulation model to evaluate the influence of those magnitudes on the irradiance profile of a light beam at a target plane after passing through the diffraction grating. To achieve this goal, the calibrated areal standards have been used in addition to good practice guides for instrument calibration combined with optical modeling to simulate the functional behavior of the optical device. Results proved that changes of hundreds of nanometers in the lateral dimensions of the grating profile lead to drastic deviations in the irradiance profile and, thus, deviation in the optical performance. Hence a change in the period and the structure width of the step grating to the limits of the calculated uncertainty (Nominal Period ± ux,y) supposes a change of down to a 50 % of decrease in the maximum peak of the irradiance profile detected. Thanks to these results, it is possible to define a range in the grating device's performance depending on the dimensional surface characterization and its uncertainty. Moreover, an in-situ measurement approach has been designed for further product quality control.

Excellent Diffusive Performance of Cold-Plasma-Exposed Activated Peanut Shell Carbon as an Electrode in Al-Air Batteries

Modern energy and ecological sustainability can be accomplished in part, by using activated bio char-based electrodes made from biomass waste in energy-producing devices like metal-air batteries and fuel cells. Herein, a simple method of combining Pyrolysis graphitization with DC glow discharge plasma is used to create highly disorder carbonaceous materials incorporating surface functional groups from a readily available and inexpensive bio waste of peanut shells. The synthesized activated Peanut shell carbon material displays remarkable supercapacitance performance in 2 M KOH at elevated specific capacitances (537 Fg−1 at 10 mVs−1) and catalytic ability for the oxygen reduction response at a half-wave peak of 0.19 V. Water contact angle and dispersion studies showed a considerable improvement in the surface’s hydrophilic following plasma treatment, and FTIR and Raman spectroscopy were also used to evaluate the surface’s functional group and micro structure. In this study, a simple, affordable, and environmentally friendly method for making activated dis ordered carbon is revealed. It is then investigated as a potential electrode for supercapacitor, metal air battery, fuel cell applications.

Construction and properties regulation of the functional host-guest micro-/nano-confined space in coordination polymers

Construction and properties regulation of the functional host-guest micro-/nano-confined space in coordination polymers

Replicated biopolymer pattern on PLLA-Ag basis with an excellent antibacterial response

The design of functional micro or nanostructured surfaces is undergoing extensive research for their intriguing multifunctional properties and for large variety of potential applications in biomedical field (tissue engineering or cell adhesion), electronics, optics or microfluidics. Such nanosized topographies can be easily fabricated by various lithography techniques and can be also further reinforced by synergic effect by combining aforementioned structures along materials with already outstanding antibacterial properties. In this work we fabricated novel micro/nanostructured substrates using soft lithography replication method and subsequent thermal nanoimprint lithography method, creating nanostructured films based on poly (l-lactic acid) (PLLA) fortified by thin silver films deposited by PVD. Main nanoscale patterns were fabricated by replicating surface patterns of optical discs (CDs and DVDs), which proved to be easy, fast and inexpensive method for creating relatively large area patterned surfaces. Their antimicrobial activity was examined in vitro against the bacteria Escherichia coli and Staphylococcus epidermidis strains. The results demonstrated that nanopatterned films actually improved the conditions for bacterial growth compared to pristine PLLA films, the novelty is based on formation of Ag nanoparticles on the surface/and in bulk, while silver nanoparticle enhanced and nanopatterned films exhibited excellent antibacterial activity against both bacterial strains, with circa 80 % efficacy in 4 h and complete bactericidal effect in span of 24 h.

Assessment of Livelihood Activities of Beneficiaries of Village Alive Development Initiative, Kwara State, Nigeria

The study assessed the livelihood activities of beneficiaries of Village Alive Development Initiative (VADI) in Kwara State, Nigeria. It specifically identified the types of livelihood of beneficiaries in the study area and assessed how the programme benefited rural communities. Data were collected using structured questionnaire administered to fifty-seven beneficiaries using three-stage sampling technique. Data generated were analyzed with descriptive and inferential statistical tools. The study revealed that the age bracket is uniformly distributed across the age groups with greater proportion (37.78%) of the respondents’ ages falling within the age bracket of above 56years.Majority of the respondents were married (91.11%) and educational exposure (84.4%). Also, about 25% (11) of the respondents earned less than ₦100,000 annually and (77.27%) made use of their personal savings to run their enterprises. The majority of farmers engaged in crop production (77.27%) and plant grains (57.14%) as their major crop produce. Also, majority (72.09%) of the Community farmers had no access to credit facilities and nearly half of the respondents (46.51%) did not practice record keeping. The study further showed that majority (56.1%) adopted the banking savings as their preferred mode of saving and (83.33%) do not belong to any existing groups and cooperatives. (64%) had never participated in any agricultural and rural development project. The study found out that access to credit facilities was the major interest of communities and existing groups were not strong enough to control market or operate as pressure group to influence access to credit facilities. Thus, the study recommends a simple and functional micro credit delivery system to the farmers in order to enable them access loan for their businesses, there should be awareness of the project in order to increase and strengthen their livelihood activities.

Multifunctional bilayer membranes composed of poly(lactic acid), beta-chitin whiskers and silver nanoparticles for wound dressing applications

Nanomaterial-based wound dressings have been extensively studied for the treatment of both minor and life-threatening tissue injuries. These wound dressings must possess several crucial characteristics, such as tissue compatibility, non-toxicity, appropriate biodegradability to facilitate wound healing, effective antibacterial activity to prevent infection, and adequate physical and mechanical strength to withstand repetitive dynamic forces that could potentially disrupt the healing process. Nevertheless, the development of nanostructured wound dressings that incorporate various functional micro- and nanomaterials in distinct architectures, each serving specific purposes, presents significant challenges. In this study, we successfully developed a novel multifunctional wound dressing based on poly(lactic acid) (PLA) fibrous membranes produced by solution-blow spinning (SBS) and electrospinning. The PLA-based membranes underwent surface modifications aimed at tailoring their properties for utilization as effective wound dressing platforms. Initially, beta-chitin whiskers were deposited onto the membrane surface through filtration, imparting hydrophilic character. Afterward, silver nanoparticles (AgNPs) were incorporated onto the beta-chitin layer using a spray deposition method, resulting in platforms with antimicrobial properties against both Staphylococcus aureus and Escherichia coli. Cytotoxicity studies demonstrated the biocompatibility of the membranes with the neonatal human dermal fibroblast (HDFn) cell line. Moreover, bilayer membranes exhibited a high surface area and porosity (> 80%), remarkable stability in aqueous media, and favorable mechanical properties, making them promising candidates for application as multifunctional wound dressings.

Stimuli-Responsive Functional Micro-/Nanorobots: A Review.

Stimuli-responsive functional micro-/nanorobots (srFM/Ns) are a class of intelligent, efficient, and promising microrobots that can react to external stimuli (such as temperature, light, ultrasound, pH, ion, and magnetic field) and perform designated tasks. Through adaptive transformation into the corresponding functional forms, they can perfectly match the demands depending on different applications, which manifest extremely important roles in targeted therapy, biological detection, tissue engineering, and other fields. Promising as srFM/Ns can be, few reviews have focused on them. It is therefore necessary to provide an overview of the current development of these intelligent srFM/Ns to provide clear inspiration for further development of this field. Hence, this review summarizes the current advances of stimuli-responsive functional microrobots regarding their response mechanism, the achieved functions, and their applications to highlight the pros and cons of different stimuli. Finally, we emphasize the existing challenges of srFM/Ns and propose possible strategies to help accelerate the study of this field and promote srFM/Ns toward actual applications.

Integrating Chinese Herbs and Western Medicine for New Wound Dressings through Handheld Electrospinning.

In this nanotechnology era, nanostructures play a crucial role in the investigation of novel functional nanomaterials. Complex nanostructures and their corresponding fabrication techniques provide powerful tools for the development of high-performance functional materials. In this study, advanced micro-nanomanufacturing technologies and composite micro-nanostructures were applied to the development of a new type of pharmaceutical formulation, aiming to achieve rapid hemostasis, pain relief, and antimicrobial properties. Briefly, an approach combining a electrohydrodynamic atomization (EHDA) technique and reversed-phase solvent was employed to fabricate a novel beaded nanofiber structure (BNS), consisting of micrometer-sized particles distributed on a nanoscale fiber matrix. Firstly, Zein-loaded Yunnan Baiyao (YB) particles were prepared using the solution electrospraying process. Subsequently, these particles were suspended in a co-solvent solution containing ciprofloxacin (CIP) and hydrophilic polymer polyvinylpyrrolidone (PVP) and electrospun into hybrid structural microfibers using a handheld electrospinning device, forming the EHDA product E3. The fiber-beaded composite morphology of E3 was confirmed through scanning electron microscopy (SEM) images. Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analysis revealed the amorphous state of CIP in the BNS membrane due to the good compatibility between CIP and PVP. The rapid dissolution experiment revealed that E3 exhibits fast disintegration properties and promotes the dissolution of CIP. Moreover, in vitro drug release study demonstrated the complete release of CIP within 1 min. Antibacterial assays showed a significant reduction in the number of adhered bacteria on the BNS, indicating excellent antibacterial performance. Compared with the traditional YB powders consisting of Chinese herbs, the BNS showed a series of advantages for potential wound dressing. These advantages include an improved antibacterial effect, a sustained release of active ingredients from YB, and a convenient wound covering application, which were resulted from the integration of Chinese herbs and Western medicine. This study provides valuable insights for the development of novel multiscale functional micro-/nano-composite materials and pioneers the developments of new types of medicines from the combination of herbal medicines and Western medicines.

Ionic Liquid‐Mediated Scanning Probe Electro‐Oxidative Lithography as a Novel Tool for Engineering Functional Oxide Micro‐ and Nano‐Architectures

AbstractFunctional oxides have extensively been investigated as a promising class of materials in a broad range of innovative applications. Harnessing the novel properties of functional oxides in micro‐ to nano‐scale applications hinges on establishing advanced fabrication and manufacturing techniques able to synthesize these materials in an accurate and reliable manner. Oxidative scanning probe lithography (o‐SPL), an atomic force microscopy (AFM) technique based on anodic oxidation at the water meniscus formed at the tip/substrate contact, not only combines the advantages of both “top‐down” and “bottom‐up” fabrication approaches, but also offers the possibility of fabricating oxide nanomaterials with high patterning accuracy. While the use of self‐assembled monolayers (SAMs) broadened the application of o‐SPL, significant challenges have emerged owing to the relatively limited number of SAM/solid surface combinations that can be employed for o‐SPL, which constrains the ability to control the chemistry and structure of oxides formed by o‐SPL. In this work, a new o‐SPL technique that utilizes room‐temperature ionic liquids (RTILs) as the functionalizing material to mediate the electrochemistry at AFM tip/substrate contacts is reported. The results show that the new IL‐mediated o‐SPL (IL‐o‐SPL) approach allows sub‐100 nm oxide features to be patterned on a model solid surface, namely steel, with an initiation voltage as low as −2 V. Moreover, this approach enables high tunability of both the chemical state and morphology of the patterned iron oxide structures. Owing to the high chemical compatibility of ILs, which derives from the possibility of synthesizing ILs able to adsorb on a wide variety of solid surfaces, IL‐o‐SPL can be extended to other material surfaces and provide the opportunity to accurately tailor the chemistry, morphology, and electronic properties within nanoscale domains, thus opening new pathways to the development of novel micro‐ and nano‐architectures for advanced integrated devices.

Physical and chemical evaluation of adhesion recovery property of aged high-viscosity asphalt based on specialized composite rejuvenators

With the wide application of porous asphalt pavement, the techniques for recycling aged porous asphalt mixture have attracted more attention for facilitating its sustainable development. One of the most critical issues is how to recover the adhesion properties of aged high-viscosity asphalt (HVA). In this study, different specialized composite rejuvenators types on the adhesive properties of aged asphalt binder were designed and evaluated for the goal of adhesion recovery. A bond strength test was used to evaluate the macroscale adhesion properties between the regenerated asphalt and aggregate. Micro-scale chemical and physical tests were utilized to discover the regeneration mechanism of specialized composite rejuvenators on asphalt adhesion. The results showed that the proposed three kinds of composite rejuvenators can effectively restore and improve the adhesive properties of aged HVA. The results of differential scanning calorimetry (DSC) represented that recycled HVA with smaller Tg and total heat absorption showed better adhesion properties. The FT-IR and AFM test results showed that the adhesion of recycled HVA is highly correlated with the C–O functional group index and micro adhesion. In addition, the concave structure in the asphalt surface is more beneficial to improve the asphalt-aggregate interface bonding, and the scheme of adding 8% optimized rejuvenator based on graft co-polymerization had the best effect, which could be promoted for the future application in the recycling of HVA in porous asphalt pavement.

Developmental framework of line edge roughness reference standards for next-generation functional micro-/nanostructures

The edge of a micro-/nanoscale line pattern fabricated by lithography is not a straight line as in the design but has a roughness. This is called the line edge roughness (LER) and is important dimensional information related to the device performance, and reference standards containing known LER values are needed for fundamental research on lithography-related technology. We propose a novel framework for developing LER reference standards that contain the necessary characteristics. The proposed framework has three main features: (i) a self-affine fractal roughness model for the development of next-generation devices; (ii) a reliable evaluation method based on LER reference metrology using SI-traceable atomic force microscopy (AFM); and (iii) a versatile evaluation method using scanning electron microscopy-based LER metrology verified by the previous AFM-based LER reference metrology. In an experiment to verify the proposed framework, we fabricated an LER reference standard by using electron-beam lithography. The results show that the proposed framework can be used to develop LER reference standards for next-generation functional micro-/nanostructures.

Supramolecular Nonwoven Materials via Thermally Induced Precursor Crystallization of Nanocrystalline Fibers/Belts for Recyclable Air Filters

Functional micro-/nanofibrous nonwovens have been widely used in both civil and military fields. However, traditional nonwoven materials preparation methods generally require special equipment and are often plagued by high-energy consumption or toxic solvent contamination. Here, a thermally induced precursor crystallization (TIPC) approach is reported for preparing macroscopic free-standing supramolecular nonwoven materials, which stemmed from the self-assembly of cocrystals of melamine and aromatic carboxylic acids. Green solvents are involved in the entire preparation process without the use of costly specialized equipment, making this strategy cost-efficient, environmentally benign, and scalable in size and quantity. Distinct nanocrystalline fibers/belts formed by hydrogen bonds and π–π interactions in thus-obtained nonwovens are tightly connected in a 3D network, constructing diverse porous fabrics with outstanding mechanical flexibility and advantageous thermal stability. These supramolecular nonwovens display selective optical transmittance and, remarkably, can be utilized as recyclable air filters. Taking advantage of the thermally reversible property of supramolecular complexes, a proof-of-concept on the closed-loop recycling of supramolecular nonwovens is realized. This work for assembling common small molecules into structurally complex architectures not only opens up promising avenues for multifunctional supramolecular materials based on synthetically facile procedures but also provides a versatile and cost-effective bottom-up approach to preparing micro-/nanofibrous nonwovens for emergent applications.

Functional Micro-/Nanostructures in Agrofood Science: Precise Inspection, Hazard Elimination, and Potential Health Risks.

Nanotechnology, biotechniques, and chemical engineering have arisen as new trends with significant impacts on agrofood science development. Advanced analytical techniques with high sensitivity, specificity, and automation based on micro-/nanomaterials for food hazard elimination have become leading research hotspots in agrofood science. Research progress in micro-/nanomaterials has provided a solid theoretical basis and technical support to solve problems in the industry. However, the rapid development of micro-/nanostructures has also raised concerns regarding potential risks to human health. This review presents the latest advances in the precise inspection and elimination of food hazards from micro-/nanomaterials and discusses the potential threats to human health posed by nanomaterials. The theoretical reference was provided for the application trend of micro-/nanomaterials in the field of agrofood science in the future.

Synergism between LDLB and true CD to achieve angle-dependent chiroptical inversion and switchable polarized luminescence emission in nonreciprocal nanofibrous films.

Chiroptical nanomaterials including chiralized advanced functional nanofibers have attracted ever-increasing interest in multi-disciplinary fields. Nowadays, electronic circular dichroism (CD) is the most widely used technique to evaluate chiral properties. Numerous studies have shown that the occurrence of linear dichroism and linear birefringence (LDLB) phenomenon in chiral micro-/nano-architectures makes it challenging to distinguish their inherent chiral information. However, tactfully combining LDLB with true circular dichroism (true CD) may lead to a new class of chiroptical materials. In this study, we demonstrate that transparent nanofibrous films infiltrated with poor solvents can show unique LDLB properties, which allows achiral nanofibrous films to exhibit these features regularly opposite Cotton signals by simply flipping the two faces of the same film or even rotating the testing angles of the sample around its optical axis in a single face. More importantly, we can quantitatively distinguish the contribution of LDLB from true CD in the chiral composite nanofibrous system and even effectively combine them into a single unity. This kind of adjustable flexible film material shows outstanding value in the field of optoelectronics. Its large intrinsic LDLB feature and angle-dependent, non-reciprocal transmission for polarized lights are exploited to fabricate programmable polarized light-emitting devices through the resin encapsulation process. This study may provide an easy and powerful way for the construction and implementation of novel polarization optical materials towards future intelligent optical encryption and advanced anti-counterfeiting devices.

ZIF-8 sacrificial-templated hollow COF architectures enabled highly efficient enrichment, determination and regulation of food hazards from infant formulas

Integration of functional micro-/nano-frameworks with various analytical techniques is favored to produce advanced and practical methods for identification, inspection, and regulation of hazards in agro-food products. Herein, two novel synthetic strategies were developed for preparation of core–shell structured ZIF-8@COF by using metal halides as the catalyst, and further construction of hollow-structured covalent organic frameworks (HCOFs) with a sacrificial template method. The HCOFs adsorbent exhibited high stability, universality and adsorption affinity for advanced glycation end products (AGEs) and aflatoxins (AFTs) than pristine COF. Combined with HPLC and HPLC-MS/MS, the applicability of this method was verified by infant formula samples with satisfying recoveries of 87.3%–98.9%. Furthermore, HCOF showed potential ability of adsorbing and removing AGEs from plasma without causing other risk. This work opens up the road for further research on the simple method to synthesis HCOF, besides, provides a technological basis for monitoring and controlling AGEs and AFTs in milk powder.