Optical Clarity Research Articles

A modified self-micro emulsifying liposome for bioavailability enhancement of quercetin and its biological effects

Quercetin (QT) is a chief dietary flavonoid with a myriad of health benefits, however, its poor solubility and low bioavailability restrict its food application. Thus, the present study aimed at enhancing its solubility using a modified self-micro emulsifying system (QT-TPGS-QS). The stability of liposome was assessed via monitoring of its particle indexes (size, zeta potential, PDI, stability towards in-vitro digestion, drug release, and encapsulation efficiency). Further, antibacterial and cellular antioxidant potential of liposomes were determined. QT-TPGS-QS exhibited good optical clarity with a loading ratio of 2.1%. The liposome showed uniform spherical and regular shape (<100 nm) with a QT release rate of 85.61% ± 0.32% in simulated in-vitro digestion. QT-TPGS-QS demonstrated superior antibacterial activity compared to QT alone against Escherichia coli, Staphylococcus aureus, and Salmonella. In-vitro antioxidant evaluation confirmed that the QT-TPGS-QS exhibited a significantly higher free radical scavenging ability than QT alone. Cellular assay confirmed that QT-TPGS-QS (15 μg/mL) exhibited a good protection effect on oxidative stress induced by H2O2. Catalase (CAT) and glutathione peroxidase (GSH-Px) levels were significantly upregulated, concurrent with a reduction of malondialdehyde (MDA) suggesting that QT-TPGS-QS might be effective in inhibiting the production of intracellular reactive oxygen species (ROS), and to be considered as food additive or in nutraceuticals.

Analytical microscopy techniques using coaxial and oblique illuminations to detect thin glass particulates generated from glass vials for parenteral drug products

Glass vials are the most widely used primary containers for the packaging of parenteral products due to their optical clarity, general inertness, and hermetic properties, but under certain circumstances, they can pose safety concerns. Most of these issues are related to the potential formation of glass particulates through delamination or precipitation, resulting from the chemical interaction between the drug product and the inner surface of the glass vial. Hence, it is imperative for pharmaceutical companies to conduct product-vial compatibility studies to determine the appropriate packaging/container closure system. To support this development activity, scientists need to develop analytical methods to detect subvisible glass particulates in parenteral products, along with the appropriate positive controls, to facilitate detection and identification. This paper outlines the utilization of coaxial/episcopic and oblique illumination microscopy, combined with spectroscopic techniques, to detect thin glass particulates generated from a modified procedure. It also showcases the importance of angle-dependent lighting in visualizing positive control samples containing thin glass particulates. The analytical microscopy techniques discussed in this paper can assist scientists in selecting suitable container closure systems for developing parenteral products.

Glass catfish inspired subaquatic abrasion-resistant anti-fouling window fabricated by femtosecond laser electrodeposition

Abstract Transparent materials utilized as underwater optical windows are highly vulnerable to various forms of pollution or abrasion due to their intrinsic hydrophilic properties. This susceptibility is particularly pronounced in underwater environments where pollutants can impede the operation of these optical devices, significantly degrading or even compromising their optical properties. The glass catfish, known for its remarkable transparency in water, maintains surface cleanliness and clarity despite exposure to contaminants, impurities abrasion, and hydraulic pressure. Inspired by the glass catfish's natural attributes, this study introduces a new solution named subaquatic abrasion-resistant and anti-fouling window (SAAW). Utilizing femtosecond laser ablation and electrodeposition, the SAAW is engineered by embedding fine metal bones structures into a transparent substrate and anti-fouling sliding layer, akin to the sturdy bones among catfish’s body. This approach significantly bolsters the window's abrasion resistance and anti-fouling performance while maintaining high light transmittance. The sliding layer on the SAAW’s surface remarkably reduce the friction of various liquid, which is the reason that SAAW owns great anti-fouling property. The SAAW demonstrates outstanding optical clarity even after enduring hundreds of sandpaper abrasion, attributed to the fine metal bone structures bearing all external forces and protect the sliding layer of SAAW. Furthermore, it exhibits exceptional resistance to biological adhesion and underwater pressure. In a green algae environment, the window remains clean with minimal change in transmittance over one month. Moreover, it retains its wettability and anti-fouling properties when subjected to a depth of 30 meters of underwater pressure for 30 days. Hence, the SAAW prepared by femtosecond laser ablation and electrodeposition presents a promising strategy for developing stable optical windows in liquid environments.

Innovative upcycling cigarette filters into high-performance cellulose nanofiber-epoxy composites

This research introduces a novel upcycling method for transforming cigarette filters—an abundant and persistent environmental waste—into high-performance epoxy composites reinforced with cellulose nanofibers. The innovation lies in extracting cellulose acetate nanofibers from used cigarette butts via a multi-step purification and electrospinning process, followed by their conversion into regenerated cellulose nanofibers through alkaline hydrolysis. This dual-fiber approach allows us to fabricate four distinct epoxy composites, each reinforced by different nanofiber types: recycled cellulose acetate nanofibers, regenerated cellulose nanofibers from recycled cigarette filters, and their commercial counterparts. Notably, this is the first time regenerated nanofibers derived from waste cigarette filters have been utilized for epoxy composite reinforcement, demonstrating a sustainable, high-value use for a major pollutant. Comprehensive characterizations, including FTIR, XRD, SEM, and contact angle measurements, confirmed the successful regeneration of cellulose nanofibers, showing improved hydrophilicity, reduced crystallinity, and uniform nanofiber morphology with diameters between 200 and 300 nm. The innovation further extends to the mechanical performance of these composites: tensile tests revealed that those reinforced with regenerated cellulose nanofibers exhibited superior tensile strength (49.5–53.8 MPa), significantly outperforming both cellulose acetate nanofiber composites (40.1–42.6 MPa) and neat epoxy resin (31.4 MPa). This marked improvement is attributed to enhanced nanofiber dispersion and interfacial adhesion within the epoxy matrix, an essential advancement over traditional composites. In addition, thermal analysis showed that all composites maintained thermal stability in the 300–400 °C range, comparable to commercial alternatives. The regenerated nanofiber-reinforced composites also displayed enhanced optical transparency due to reduced light scattering, making them ideal candidates for applications requiring both mechanical strength and optical clarity. By pioneering the use of cigarette filter waste for fabricating advanced cellulose nanofiber composites, this study presents an eco-friendly approach to addressing environmental pollution while creating sustainable materials with superior mechanical, thermal, and optical properties.

Advancements in Polymer Biomaterials as Scaffolds for Corneal Endothelium Tissue Engineering

Corneal endothelial dysfunction is a leading cause of vision loss globally, frequently requiring corneal transplantation. However, the limited availability of donor tissues, particularly in developing countries, has spurred on the exploration of tissue engineering strategies, with a focus on polymer biomaterials as scaffolds for corneal endotlhelium regeneration. This review provides a comprehensive overview of the advancements in polymer biomaterials, focusing on their role in supporting the growth, differentiation, and functional maintenance of human corneal endothelial cells (CECs). Key properties of scaffold materials, including optical clarity, biocompatibility, biodegradability, mechanical stability, permeability, and surface wettability, are discussed in detail. The review also explores the latest innovations in micro- and nano-topological morphologies, fabrication techniques such as electrospinning and 3D/4D bioprinting, and the integration of drug delivery systems into scaffolds. Despite significant progress, challenges remain in translating these technologies to clinical applications. Future directions for research are highlighted, including the need for improved biomaterial combinations, a deeper understanding of CEC biology, and the development of scalable manufacturing processes. This review aims to serve as a resource for researchers and clinician–scientists seeking to advance the field of corneal endothelium tissue engineering.

Innovative sample preparation using alcohol dehydration and high refractive index medium enables acquisition of two-channel super-resolution 3D STED image of an entire oocyte.

Super-resolution (SR) microscopy is a cutting-edge method that can provide detailed structural information with high resolution. However, the thickness of the specimen has been a major limitation for SR methods, and large biological structures have posed a challenge. To overcome this, the key step is to optimise sample preparation to ensure optical homogeneity and clarity, which can enhance the capabilities of SR methods for the acquisition of thicker structures. Oocytes are the largest cells in the mammalian body and are crucial objects in reproductive biology. They are especially useful for studying membrane proteins. However, oocytes are extremely fragile and sensitive to mechanical manipulation and osmotic shocks, making sample preparation a critical and challenging step. We present an innovative, simple and sensitive approach to oocyte sample preparation for 3D STED acquisition. This involves alcohol dehydration and mounting into a high refractive index medium. This extended preparation procedure allowed us to successfully obtain a unique two-channel 3D STED SR image of an entire mouse oocyte. By optimising sample preparation, it is possible to overcome current limitations of SR methods and obtain high-resolution images of large biological structures, such as oocytes, in order to study fundamental biological processes. Lay Abstract: Super-resolution (SR) microscopy is a cutting-edge tool that allows scientists to view incredibly fine details in biological samples. However, it struggles with larger, thicker specimens, as they need to be optically clear and uniform for the best imaging results. In this study, we refined the sample preparation process to make it more suitable for SR microscopy. Our method includes carefully dehydrating biological samples with alcohol and then transferring them into a mounting medium that enhances optical clarity. This improved protocol enables high-resolution imaging of thick biological structures, which was previously challenging. By optimizing this preparation method, we hope to expand the use of SR microscopy for studying large biological samples, helping scientists better understand complex biological structures.

Easy fabrication of PVA-CaO-CuO composite films for efficient photocatalyst: Towards distinct luminescence property, morphology and thermal stability

PVA-CuO-CaO composites in the film form were synthesized by loading the different compositions of metal oxides (CuO and CaO) ranging from 5 to 25 wt% via solvent casting approach. The applications of the prepared composites as photocatalysts were assessed together with the findings of photoluminescence (PL) characteristics, optical clarity, morphological features, and thermal properties. Fourier-transformed infrared (FTIR), ultraviolet–visible (UV–vis), and photoluminescence (PL) spectra exposed the systematic and viableintegration of metal oxides (CuO-CaO) into the PVA matrix in PVA-CuO-CaO composites. The modifications of PL property of PVA-CuO-CaO composites were recognized rather than bare PVA. The prepared composite films exhibited excellent optical transparency irrespective of the addition of metal oxides. Both TGA and DSC data showed that the thermal properties of the composites could be significantly enhanced by incorporating CuO and CaO. DSC measurements demonstrated that the Tm of PVA-CuO-CaO composites is improved substantially (∼7 to 38 °C) than PVA. The distinct morphological structures of the obtained composites were identified with variations in CuO and CaO addition remaining diameter in the 30–200 nm range. The photocatalytic assessments revealed the better photocatalytic performance of PVA-CuO-CaO composites for removing methylene blue (MB) than bare PVA. By eliminating organic pollutants, the current study may provide a new perspective on the preparation of water-processable PVA-CuO-CaO photocatalysts for wastewater management.

Enhanced mechanical properties in transparent mullite glass-ceramics synthesized from EMT-type zeolites via spark plasma sintering

Transparent glass-ceramics offer a unique combination of optical clarity and the mechanical strength of ceramics, making them ideal for various advanced applications such as cell phone screens and telescope mirrors. However, traditional fabrication methods involve high temperatures and long processing times, which result in high energy consumption and limitations in material integration. In this study, we explore the fabrication of transparent mullite glass-ceramics from EMT-type zeolites using the spark plasma sintering (SPS) technique to address these challenges. By varying the concentrations of ammonium salts to replace Na+ in the zeolite, we modified the SiO2+Al2O3 content and successfully synthesized the mullite glass-ceramics at 950 °C. The resulting glass-ceramics exhibited high transmittance (>65 % in the visible region), improved mechanical properties with a Young's modulus up to 103 GPa, a Vickers hardness of 8.0 GPa, and an indentation fracture toughness of 1.8 MPa m1/2. X-ray diffraction and Raman spectroscopy confirmed the formation of mullite phases, with increased crystallinity and a strengthened glass structure, correlating with higher SiO2+Al2O3 content. The study demonstrates the potential of using high Al/Si ratio molecular sieves as precursors for high-performance glass-ceramics, offering significant advancements in both optical and mechanical properties.

Bio-based polylactic acid labware as a sustainable alternative for microbial cultivation in life science laboratories

Single-use plastics (SUPs) in life science laboratories account for approximately 5.5 million tonnes of waste per year globally. Of SUPs used in life science laboratories, Petri dishes, centrifuge tubes, and inoculation loops are some of the most common. In order to reduce the reliance on petrochemical-based SUPs in the life science research laboratory and minimize the negative environmental impacts associated with SUPs, this research investigates the applicability of polylactic acid (PLA) in single-use labware as a replacement for petrochemical-based plastics. PLA is one of the most well-studied biodegradable plastics that can be produced from sustainable resources. Commercially available PLA was used to 3D print a select range of labware to test the suitability of PLA-based material for routine microbiology work. An injection moulded PLA-based Petri dish was also designed and produced, for increased optical clarity. The biocompatibility was tested against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus epidermidis) strains of bacteria. The PLA-based labware did not negatively impact the cell growth, viability, and metabolic activity of the bacterial cultures. The injection moulded PLA Petri dish showed a reduced colony forming unit count for the Gram-negative E. coli strain compared to the polystyrene Petri dish, ∼1.5 × 109 CFU/mL and ∼3.0 × 109 CFU/mL respectively, during late-exponential growth. The colony counts were, however, in the same order of magnitude. This observed difference may be due to the internal environment inside the Petri dish, hence the internal O2 concentration, humidity, and temperature during bacterial growth were investigated. This work demonstrates, for the first time, a full successful workflow of bacterial growth using a sustainable bioplastic, providing a pathway to reducing the environmental impacts of SUPs in life science laboratories.

Construction of living-cell tissue engineered amniotic membrane for ocular surface disease

BackgroundHuman amniotic membrane (AM) transplantation has been applied to treat ocular surface diseases, including corneal trauma. The focus of much deliberation is to balance the mechanical strength of the amniotic membrane, its resistance to biodegradation, and its therapeutic efficacy. It is commonly observed that the crosslinked human decellularized amniotic membranes lose the functional human amniotic epithelial cells (hAECs), which play a key role in curing the injured tissues.Methods and resultsIn this study, we crosslinked human decellularized amniotic membranes (dAM) with genipin and re-planted the hAECs onto the genipin crosslinked AM. The properties of the AM were evaluated based on optical clarity, biodegradation, cytotoxicity, and ultrastructure. The crosslinked AM maintained its transparency. The color of crosslinked AM deepened with increasing concentrations of genipin. And the extracts from low concentrations of genipin crosslinked AM had no toxic effect on human corneal epithelial cells (HCECs), while high concentrations of genipin exhibited cytotoxicity. The microscopic observation and H&E staining revealed that 2 mg/mL genipin-crosslinked dAM (2 mg/mL cl-dAM) was more favorable for the attachment, migration, and proliferation of hAECs. Moreover, the results of the CCK-8 assay and the transwell assay further indicated that the living hAECs’ tissue-engineered amniotic membranes could facilitate the proliferation and migration of human corneal stromal cells (HCSCs) in vitro.ConclusionsIn conclusion, the cl-dAM with living hAECs demonstrates superior biostability and holds significant promise as a material for ocular surface tissue repair in clinical applications.

Physical aging of a glassy polymer in cultural heritage conservation

AbstractArtworks, particularly easel paintings, are multi‐component materials intended to last indefinitely. The protective coatings applied to these artworks often consist of amorphous glass‐like polymers, which undergo slow physical aging and structural recovery below their glass transition temperature. This process alters key physical properties such as mechanical strength, optical clarity, and thermal stability over extended periods. This study investigates the time‐dependent evolution of these properties in Laropal A81, a widely used synthetic resin for cultural heritage conservation, particularly as a replacement for ancient varnishes. The investigation involves characterization of enthalpy recovery via differential scanning calorimetry, refractive index evolution via refractometry, and creep compliance evolution via rheological measurements. The aging behavior of Laropal A81 is further analyzed using the Kohlrausch–Williams–Watts function and the Tool–Narayanaswamy–Moynihan model, enabling the quantification of critical dynamic parameters such as activation energy, nonlinearity, partition coefficients, and non‐exponentiality. The gained insights into the long‐term behavior of this coating's properties can be valuable for improving preservation and restoration strategies for cultural heritage.

Silicone-polyurea based clear viscoelastic films for flexible displays, impact of diisocyanate, chain extender, soft segment molecular weight, and hard segment contents

Clear viscoelastic film (CVF), an optically clear type of press sensitive adhesive (PSA), is crucial for bonding different functional layers together in a display module. With the rapid growth of consumer electronics, foldable display devices offer new challenges to CVF, such as optical clarity, low modulus, low glass transition temperature (Tg), good stress-relaxation, good recoverability, and decent adhesion strength. However, there are some contradictories in combining above properties (e.g., good stress-relaxation vs. good recoverability). Silicone polymers can impart softness and prompt elastic recovery over a wide range of temperatures, thereby making their advantageous features suitable for CVF candidates in flexible display devices. In our previous work, an optimum sample of CVF based on low-hard-segment silicone polyurea (LH-SPU) exhibited well-balanced viscoelasticity for flexible displays. In this work, the impact of diisocyanate, chain extender, soft segment molecular weight, and hard segment contents on SPU elastomeric CVFs (SPU CVFs) for flexible displays was further detailly and systematically evaluated. The different components of SPU can be readily adjusted to prepare CVFs with different properties, such as selectable range of modulus (104 ∼ 105 Pa), temperature plateau (−40 ∼ 120 °C), recoverability (78.15 ∼ 90.97 % under 500 % axial strain), creep-resistance (above 85.5 % creep-recoverability under shear stress of 20, 30, 40, 50 KPa), initial adhesive work (0.17 ∼ 2.23 mJ), and 180° peel strength (9.25 ∼ 14.6 N/25 mm after placing 24 h). Furthermore, the SPU CVFs had undergone 200,000 successive folding reliability tests without any cracking or delamination to verify their potentiality in flexible display devices.

A facile route to fabricate transparent and mechanically robust glass-fabric reinforced composites via refractive index matching and tow-spreading technique

There are challenges to fabricate GFRPs with high optical clarity and mechanical performance due to the inevitable chromatic dispersion and yarn crimp in the fabric. Herein, a facile route to fabricate transparent glass-fabric reinforced composites is reported using refractive index matching and tow-spreading technique. By introducing different amount of BMA, the epoxy matrix could match the refractive index of glass fibers at different wavelength. The fabricated composites exhibit intriguing pale blue/blue, dark blue/ purple, purple-pink/pink chromatic dispersion, respectively. Among them, the 0.2 mm-thick GFRP with 4 % BMA (fiber volume fraction ≈ 50.4 %) exhibits the highest total transmittance (89.5 %) and lowest haze (3.4 %). Compared with commercial standard-tow fabric, composites with spread-tow fabrics exhibits less chromatic dispersion and transparency loss. Moreover, simultaneously reinforcing and toughening effect could be observed in the composites with BMA modified matrix. The optimized composites possess tensile strength of 289 MPa and flexural strength of 416 MPa.

Role of Dopant in Enabling Electrodeposition of Polymer Thin Films with High Solar Transmittance Modulation

Buildings consume approximately one-third of the energy used in developed countries, with much of this energy tied to building heating and cooling. Electrochromic “smart” windows have the potential to mitigate some of this energy use through on-demand modulation of solar energy transmission. Therefore, electrochromic window devices based on low cost and facile solution-based processing routes are sought. In this work, we describe the electropolymerization and deposition of electrochromic poly(arylamine) thin films with exceptional broadband solar transmittance modulation, reaching ΔT sol values of over 60% (Figure 1). Through high-resolution, near-field spectroscopic imaging we show that the structure of the acid dopant present in the electrodeposition solution plays a key templating role that determines the electrochromic performance of these films. Our findings indicate that polyanionic dopants are especially adept at directing polymer chain conformational order, which in turn improves charge delocalization and transport. These factors lead to films with high smoothness and optical clarity through the visible (T lum > 80%) and near-infrared ranges. Further details regarding the cycling stability of these films and their integration into full electrochromic devices will be discussed. In summary, this work demonstrates the value of polyanionic dopants for templating high quality electrochromic polymer thin films capable of energy-relevant solar transmittance modulation for smart window applications. Figure 1

Antibiofilm Activity of Silver Nanoparticles Synthesized from Seed Extract of Garcinia Kola

Silver nanoparticles from plant extracts are novel compounds with potential antimicrobial properties. Studies on antibiofilm activity of Ag-NPs synthesized from seed extracts of Garcinnia kola (G. kola) were carried out. Garcinnia kola seed were obtained from Keffi market, Nigeria. Green synthesis of Ag-NPs from the seed was carried using 2.0mm silver-nitrate by use of standard method. The Ag-NPs synthesized from the seed were characterized using former transmission infrared (FITR) spectroscopy and scanning election microscope. The antimicrobial activity of the Ag-NPs against Klebsiella pneumonia (Kp) isolates were carried out using agar dilution method. The biofilm formation by the isolates as well as the inhibition and dissolution by Ag-NPs were eval__uated using microplate method. The functional groups detected in the Ag-NPs were N-H, C-O, N-O, and CΞC with peaks 906.5cm-1,1282.2cm-2, 13344cm-1, 1550.6cm-1 and 217.1cm-1 respectively. The size of the particles ranges from 179-296nm. The minimum inhibiting concentration (MICs) of the particles and meropenem against the isolates were 250µg/l and 4.0µg/l. The functional inhibiting concentrates of the particles were 1.0. The optical clarity of biofilm formed by the isolates was 2.073 and 2.049. the percentage biofilm inhibiting effects of the particles was highest apart. KpC (K. Pneumoniae ATCC BAA 1075) with percentage inhibit ranges from 27.28-21.67% at 80-12.5% of the MICs. The percentage inhibiting effect of Ag-NPs in with meropenem was highest at MICs but low in MIC 12.5 with percentage inhibition 28.26% and 27.18%. The Ag-NPs alone and antibacterial activity and biofilm inhibiting effect while Ag-NPs in with meropenem had effect but against isolate but with potential antibiofilm activity.

Empowering PLA Bioplastics: Elevating applications horizon through groundbreaking Eco-Innovative Fibrillation, chain Extension, and crosslinking techniques

This comprehensive study introduces pioneering techniques in the toughening of polylactic acid (PLA) by incorporating thermoplastic polyurethane (TPU) nanofibrils, leveraging two distinct crosslinking methods to significantly enhance the material’s mechanical performance. Method 1 employs a silane/moisture crosslinking process, whereas Method 2 utilizes a tailored diisocyanate crosslinking approach, offering a more environmentally sustainable alternative. Molecular structural analysis was performed extensively by using X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR), gel permeation chromatography (GPC), rheological assessments, scanning electron microscopy (SEM), and differential scanning calorimetry (DSC). Method 2 not only preserves TPU nanofibrils but also elevates the mechanical properties of PLA-TPU composites beyond the capabilities of Method 1. Notably, by leveraging the simultaneous crosslinking of TPU and chain extension of PLA with the tailored diisocyanate approach, we enhance PLA’s mechanical properties and energy absorption capabilities. These advancements are achieved without a high rubber content, which typically compromises strength/stiffness, thermomechanical stability, crystallization, and transparency of PLA. The resulting composites prepared via Method 2 display remarkable increases in tensile toughness, ranging from 30-60 MPa, and impact strength, achieving a span of 60–140 J/m. This is primarily due to the occurrence of a brittle-to-ductile transition (BDT) at only 3 wt% nanofibril TPU content while maintaining a high PLA modulus of 3 GPa. This critical balance between chain-extending and crosslinking reactions ensures the maintenance of PLA’s inherent strength/stiffness, crystallization, and optical clarity. The research presented here marks a significant shift in the development of tougher, more thermally stable, transparent, and sustainable polymer blends and composites. Method 2, with its tailored fiber size reduction (90–280 nm), and environmental consciousness, broadens the horizon of PLA’s applications.

Evaluation of visual and optical quality following phacoemulsification cataract surgery with diffractive multifocal intraocular lens implantation: An observational study.

The assessment of patient satisfaction following cataract surgery is heavily reliant on the evaluation of visual quality, specifically after the placement of diffractive multifocal intraocular lenses (MIOLs) under varying pupil conditions. The objective of this study was to examine the visual and optical clarity following cataract phacoemulsification and the use of Tecnis ZMB00 MIOL for implantation. The study involved 116 individuals (135 eyes) who received cataract phacoemulsification and underwent Tecnis ZMB00 MIOL implantation. Assessments were conducted 1 week and 3 months after the surgery. These assessments involved measuring uncorrected and corrected visual acuity for distant, intermediate, and near vision. Additionally, scatter light values and wavefront aberrations were measured under different aperture settings of 3 and 5 mm. There was no noticeable disparity in visual acuity between 1 week and 3 months after the surgery. After 3 months of surgery, there was a considerable decrease in scatter light values and spherical aberrations compared to the values observed 1 week after surgery, under the setting of a 5 mm aperture. Moreover, the modulation transfer function values showed a significant rise after 3 months following the surgery, particularly under the 5 mm aperture condition. The most substantial increase was observed at the intermediate spatial frequency of 20 cycles per degree (cpd), in comparison to the values obtained 1 week after the operation. The combination of cataract phacoemulsification and Tecnis ZMB00 MIOL implantation yielded favorable visual acuity at various distances for patients. Furthermore, enhancements in the measurements of scattered light, higher-order aberrations, and modulation transfer function values were noted 3 months after the surgical procedure, specifically under the condition of a 5 mm pupil. These findings suggest an increase in visual clarity and night vision to a certain degree.

Bioinspired, anti-fogging and de-icing transparent surfaces with flexible property

In cold environments, natural phenomena like icing, frost, and fog can significantly impede the functionality of optical windows. Consequently, there is a growing demand for optical windows that demonstrate anti-fogging and de-icing characteristics while maintaining flexibility and transparency with high optical clarity. The development of cost-effective and straightforward anti-fogging and de-icing elements encounters various challenges. The remarkable visual acuity of polar bear eyes in challenging weather conditions can be attributed to a tear film that covers the cornea and the thermoregulatory characteristics of their eyeballs. Inspired by the anti-fogging and anti-icing properties of polar bear eyes, a new flexible, transparent surface with heating capabilities has been developed. To address the limitations of conventional slippery surfaces that solely offer anti-fouling properties, a flexible internal heating unit is integrated into the slippery surface through a layered nesting technique to emulate the homothermal features of polar bear eyeballs. The slippery property of the PDMS surface can be attributed to a gel layer containing an auto-secretory lubricant. To preserve its optical properties, a new processing method that combines liquid metal microfluidics and femtosecond laser processing is employed. This technique can create narrow channels with a high length-to-diameter ratio, thereby reducing the impact on the transmission rate. The sample demonstrates self-cleaning, resistance to dust and pollution, and efficient electrical heating properties. Testing on fogging and freezing validates the practicality and effectiveness of these substances for applications in anti-fogging and de-icing.

Towards a zero-waste chemcycling of thermoset polymer composites: Catalyst assisted mild solvolysis for clean carbon fiber liberation and circular coating development

Thermoset materials and their reinforced composites are widely employed in the aircraft, wind energy and construction sectors. Their 3D-crosslinked network and their chemical and physical heterogeneity make them particularly difficult to be recycled. Nowadays, the management of composite scraps and end-of-life waste is still based on landfilling or incineration practices, which are clearly non-compliant with the principles of the circular economy. In this work, a catalysed solvolysis process in mild conditions (T = 180 °C, t = 1–3 h, catalyst 1–7 wt%) was applied for the chemical recycling (chemcycling) of anhydride-cured epoxy resins and their carbon fiber reinforced composites. The selection of the hydroxylated solvents followed thermodynamic considerations (Hansen solubility parameters) and green chemistry principles. The quality of the liberated fibers was studied through thermogravimetric analysis, scanning electron microscopy and single-fiber micromechanical testing, highlighting high surface purity and 100% retention of their pristine mechanical properties (Young's modulus, elongation at break and ultimate strength). The organic recyclates were characterized through gel permeation chromatography, Fourier-transform infrared spectroscopy and chemical titration, and directly reused as hydroxylated binders for the formulation and application of bicomponent polyurethane protective coatings. The resulting coatings were characterized by high chemical resistance (> 100 double rubs at methyl-ethyl ketone test), high surface scratch hardness (3H to 5H), good substrate adhesion (1.5–4 MPa), and excellent optical clarity and surface gloss. These results demonstrate the potential zero-waste reusability of all fractions derived from the chemical recycling of carbon fiber reinforced composites, in line with the principles of the circular economy.

Optical bonding utilizing aqueous Al2O3–P2O5-lactate sol-gel adhesives

In the field of optical bonding, traditional optical adhesives typically contain toxic organic polymers and solvents, limiting their widespread application. Hence, there is an urgent need for environmentally friendly aqueous adhesives. While there have been efforts to develop green adhesives, few report their performances with optical substrates. The unique requirements for optical adhesives include: optically transparent; the refractive index match of the substrate; minimal stress during and after curing. This presents a challenge to ensure compatibility between green and optical. This study introduces a novel sol-gel adhesive derived from an Al2O3–P2O5-lactate system. This adhesive is biocompatible, uses water as the sole solvent. It exhibits exceptional optical clarity, with more than 99 % transparency in the visible light and near-infrared regions. Furthermore, it provides reliable bonding strength, particularly when bonded with sapphire crystal substrates, reaching a maximum of 5.96 MPa. Interfacial chemistry analysis reveals the critical role of acidic components (such as phosphoric and lactate groups) in adhesives accounted for the bonding mechanism. By increasing the molar ratio of phosphoric acid, the bonding strength of adhesive was significantly enhanced across various substrates. This sol-gel adhesive not only adheres to green chemistry principles but also shows promising potential for optical bonding applications.