Homogeneous Porous Structure Research Articles

Interfacial engineering of ZnS-FeS heterostructure accelerates Li2S2 reduction and impedes the dendritic Li growth

The andante electrocatalytic conversion and grievous shuttle effect of lithium polysulfides (LiPSs) lead to stagnant applications of lithium-sulfur (Li-S) batteries. Plentiful catalysts such as ZnS-FeS heterostructures have been employed to solve those problems. However, the mechanism of this heterostructures on sulfur reduction reaction (SRR) especially the conversion of Li2S2 to Li2S (Li2S2RR) and Li+ migration has not been revealed. Herein, a ZnS-FeS heterostructures embedded in hierarchical porous carbon (ZnS-FeS/HPC) was demonstrated that can act as effective catalyst to accelerate Li2S2RR and promote the Li+ diffusion simultaneously. This improvement can be attributed to the moderate adsorption energy and lower d-band center of the heterostructures to reaction intermediates. Moreover, with both homogeneous porous structure and abundant polarity sites, the modified separator using ZnS-FeS/HPC was endowed with selectivity to promote uniform Li+ flux and migration, as well as impede the dendritic Li growth and LiPSs shuttling. Benefited from above advantages, the batteries exhibited superior initial capacity of 1674.7 mAh/g (current density: 0.2C). Even at 3C, the batteries can cycle steadily for over 1500 cycles along with ultralow rate of capacity decay (0.044 %). This work opens up a new insight to explore bidirectional catalyst for realizing remarkable performance Li-S batteries.

Superior mechanical properties of an additively manufactured gradient lattice structure through FEM simulation and in-situ compression tests

Currently, the increasing incidence of bone defects and damage due to diseases and trauma, the treatment of bone defects usually uses autologous bone graft or allogeneic bone graft, however, the amount of autologous bone is limited, and there is also the risk of infection at the site of bone extraction, and allogeneic bone graft also faces problems such as disease transmission and immune rejection. In summary, artificial bone provides a new option for patients. This study investigates the mechanical properties of homogeneous and gradient Gyroid and Diamond porous structures, designed with average porosities of 50%, 60%, and 70%, using triply-periodic minimal surface models for artificial joints. Finite Element Method simulations and compression tests were employed to characterize the mechanical properties of Ti6Al4V porous scaffolds fabricated using the selective laser melting technique. The measured elastic modulus of the scaffolds ranged from 6.24 to 10.5GPa, meeting the requirements for orthopedic implants. Gyroid structures were shown to exhibit superior nominal stiffness compared to Diamond structures at equivalent porosity levels. Furthermore, the linear gradient porous structures demonstrated significantly higher elastic modulus, yield strength, and compressive strength compared to homogeneous porous structures, with increases of 66.9%, 20.3%, and 16.5%, respectively. The energy absorption capacity of the linear gradient porous structure was also found to be 3.3-fold greater than that of the homogeneous structure.The lightweight design of this linear gradient porous structure provides the basis for bone implants for biomedical applications.

Effect of freeze-thaw processes on the water-absorption ability and mechanical properties of hydrogel pads with chitosan/poly(vinyl alcohol) based on citrate crosslinks.

In this study, the effect of freeze-thaw (F-T) processes on the mechanical and water absorption performance of citrate cross-linked chitosan/poly(vinyl alcohol) hydrogel pads was evaluated. An excellent cross-linking of 4% (w/w) citrate was indicated by enhanced peak strength in Fourier-transform infrared spectroscopy and X-ray diffraction patterns, which was applied to the subsequent F-T process. The results in the deswelling rate, water contact angle, and relaxation time of samples exhibited a tendency to decrease and then increase with increasing F-Tcycles, reaching a minimum of 0.08, 16.48°, and 3.92ms in the third cycle, respectively. The swelling rate showed opposite trends with a maximum of 5.92. In addition, scanning electron microscopy observation and mechanical testing confirmed homogeneous pore structure and excellent mechanical properties during the third cycle. This study can provide technical support for fabricating hydrogel absorbent pads and their application in meat products.

Innovative use of wastewater-extracted Arabinoxylans: Elevating steamed bread texture and structure

Water-extractable arabinoxylans (WEAX) are utilized as additives to enhance the properties of flour-based products. This study investigates the impact of WEAX, extracted from wastewater, on the texture, water distribution, and microstructure of steamed breads. The results showed that WEAX positively affected the hardness, moisture distribution and stomatal area ratio of steamed breads. WEAX reduced the hardness of steamed breads by 36 % among the various treatments, suggesting that WEAX formed cross-linked polymers with gluten proteins through covalent and hydrogen bonds, which reduced the hardness of steamed breads. Notably, the gluten network is improved by the addition of WEAX, resulting in a denser and more homogeneous pore structure in the dough. Overall, the incorporation of WEAX positively influenced the texture, water distribution, and porosity of steamed breads. This finding offers a theoretical foundation for the utilization of WEAX, extracted from wastewater, in the industrial production of steamed bread and other flour-based products.

Pore Uniformity Effect of Porous Transport Layers on Bubble Behaviors in PEM Water Electrolysis

Hydrogen, a clean energy source with high energy density and long-term storage potential, is gaining attention as a viable alternative to fossil fuels. Among various water electrolysis methods, Proton Exchange Membrane Water Electrolysis (PEMWE) is suitable for green hydrogen production due to its ability to operate efficiently at high current densities and low temperatures. A key component of PEMWE is the Porous Transport Layer (PTL), which facilitates oxygen gas discharge and water supply. However, to enable practical use of PEMWE at high current densities, effective oxygen removal without accumulation in the PTL is critical. While previous studies have explored the structural characteristics of PTL, research quantifying the effect of PTL pore uniformity on PEMWE performance remains limited. This study compared PTL samples with different pore uniformities using X-ray CT, investigated how these differences affect PEMWE performance, and analyzed bubble detachment characteristics on the PTL surface using high-speed imaging.A specially designed cell with a transparent acrylic end plate was used to observe internal flow in the PEMWE system. The bubble detachment characteristics, including the number, frequency, and diameter of detached bubbles, were analyzed. The homogeneous PTL followed a normal distribution, while the inhomogeneous PTL exhibited a broader pore size range, deviating from this distribution. These structural differences led to significant performance variations. The homogeneous PTL had a bubble detachment rate of 9.49 bubbles/mm2, with an average detachment frequency of 30.5 Hz and a detachment diameter of 2.21 mm. In contrast, the inhomogeneous PTL exhibited a significantly lower detachment rate of 0.30 bubbles/mm2, a higher detachment frequency of 78.2 Hz, and a larger detachment diameter of 22.4 mm. Furthermore, when comparing the departure velocity, calculated by multiplying the detachment frequency by the bubble diameter, the homogeneous PTL achieved a velocity of 289.3 mm/s, approximately 3.2 times faster than the 89.6 mm/s observed in the inhomogeneous PTL. These findings suggest that a more uniform pore structure enables faster and more efficient gas removal, leading to enhanced PEMWE performance. Additionally, the high departure velocity in the homogeneous PTL indicates a more effective two-phase flow, which contributes to the improved water supply and gas discharge, thereby optimizing overall cell efficiency.The homogeneous pore structures promote efficient gas discharge and water supply, leading to improved cell performance. These findings show the importance of designing PTLs with uniform internal pore structures to optimize PEMWE operation. Acknowledgment This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. RS-2023-00208497, RS-2023-00219369).

Controllable preparation and multifunctional application of high-strength porous anorthite ceramics

Porous anorthite ceramics, as emerging green materials, garner significant interest in applications such as catalyst carriers, thermal insulation, and sound absorption due to their distinctive structural and functional attributes. In the present study, porous ceramics with anorthite as the main phase were prepared using the natural minerals kaolin, calcite, and quartz as raw materials, combined with a simple and environmentally friendly foam gel-casting method. By adjusting the additive content, we optimized the viscosity and stability of the slurry, and further investigated the impact of the slurry's foaming capacity on the resulting porosity, pore size, mechanical strength, and other key properties of the ceramics. Notably, the porous anorthite ceramic with 15 g/L of foaming agent demonstrated a porosity of 70.57 %, a bulk density of 0.81 g/cm3, and a thermal conductivity of 0.26 W/(mK), along with a commendable compressive strength of 8.85 MPa due to the homogeneous sub-spherical pore structure and plate-like anorthite grains. The suitability of these porous ceramics for catalyst carrier applications was confirmed through the effective photodegradation of a methyl orange solution.

Design and performance of a foamed ceramic prepared by sintering using boron carbide as a foaming agent

To meet the requirements of microwave penetration in military applications, the technical potential of preparing foamed ceramics (FCs) with low permittivity and reduced preparation costs by using desalted sea sands as the main raw material and boron carbide (B4C) as a foaming agent was investigated. The results of the orthogonal experiment demonstrate that the FCs prepared from a material system containing 3 wt% B4C, 2 wt% Fe2O3 and 4 wt% Na2CO3 exhibit the optimal overall performance. The performance of the FCs is strongly influenced by the sintering temperature, but less so by the sintering time. The FCs sintered at 1000 °C for 10 min have a high total porosity of 72 %, a high compressive strength of 9.7 MPa due to their homogeneous internal pore structure with small pore diameter, a high closed porosity of 71 % due to their dense smooth surface and intact pore walls, and a low permittivity of (2.09–2.25)+j(0.014–0.019) in the X–band due to their high porosity and simple composition, indicating that they are a promising multifunctional material for microwave penetration.

Electromagnetic Interference Shielding Films: Structure Design and Prospects.

The popularity of portable and wearable flexible electronic devices, coupled with the rapid advancements in military field, requires electromagnetic interference (EMI) shielding materials with lightweight, thin, and flexible characteristics, which are incomparable for traditional EMI shielding materials. The film materials can fulfill the above requirements, making them among the most promising EMI shielding materials for next-generation electronic devices. Meticulously controlling structure of composite film materials while optimizing the electromagnetic parameters of the constructed components can effectively dissipate and transform electromagnetic wave energy. Herein, the review systematically outlines high-performance EMI shielding composite films through structural design strategies, including homogeneous structure, layered structure, and porous structure. The attenuation mechanism of EMI shielding materials and the evaluation (Schelkunoff theory and calculation theory) of EMI shielding performance are introduced in detail. Moreover, the effect of structure attributes and electromagnetic properties of composite films on the EMI shielding performance is analyzed, while summarizing design criteria and elucidating the relevant EMI shielding mechanism. Finally, the future challenges and potential application prospects of EMI shielding composite films are prospected. This review provides crucial guidance for the construction of advanced EMI shielding films tailored for highly customized and personalized electronic devices in the future.

Fluorescence visualization dynamics of carbonated water injection processes in homogeneous glass micromodels

Understanding the flow behavior of oil–water phases in porous media is crucial for revealing the kinetic mechanisms underlying oil–water movement. In this study, we designed and constructed a fluorescence visualization experimental platform for carbonated water injection (CWI). We evaluated the effects of nine distinct injection rates on oil production and CO2 sequestration capabilities using three types of homogeneous porous structure micromodels. The microscale oil–water seepage behavior at the pore scale was also explored. The experimental results indicate that optimally increasing the injection rate can improve displacement efficiency, whereas excessively high rates may lead to viscous and capillary fingering. The geometry of the micromodels, particularly the hexagonal matrix, demonstrates potential advantages in enhancing oil displacement due to its uniform flow paths. The capillary number (Ca) significantly influences oil droplet capture behavior within micromodels. For instance, micromodel A captures the largest ganglion area at low Ca values, with a noticeable reduction in average ganglion area as Ca increases. Conversely, micromodels B and C exhibit similar trends in ganglion size variation at high Ca values, suggesting a more uniform impact of pore structure on oil droplet capture behavior. At elevated Ca values, capillary forces exert a more uniform and controlled effect on oil droplet capture and release, minimizing size variability. Additionally, the injection rate plays a critical role in CO2 sequestration, with higher rates promoting convective mixing between CO2 and reservoir fluids, thereby enhancing dissolution and storage efficiency. The complexity of the pore structure, characterized by the presence of micropores and macropores, affects the dissolution kinetics and mobility of CO2, influencing sequestration efficiency. These experimental findings provide valuable insights into the dynamics of oil–water motion and the potential for enhanced oil recovery (EOR) and CO2 storage, offering essential guidance for optimizing CWI strategies in the petroleum industry.

Designing a Refined Multi-Structural Polymer Electrolyte Framework for Highly Stable Lithium-Metal Batteries.

Rational structural designs of solid polymer electrolytes featuring rich interface-phase morphologies can improve electrolyte connection and rapid ion transport. However, these rigid interfacial structures commonly result in diminished or entirely inert ionic conductivity within their bulk phase, compromising overall electrolyte performance. Herein, a multi-component ion-conductive electrolyte was successfully designed based on a refined multi-structural polymer electrolyte (RMSPE) framework with uniform Li+ solvation chemistry and rapid Li+ transporting kinetics. The RMSPE framework is constructed via polymerization-induced phase separation based on a rational combination of lithiophilic components and rigid/flexible chain units with significant hydrophobic/hydrophilic contrasts. Further refined by coating a robust polymer network, this all-organic design endows a homogeneous micro-nano porous structure, providing a novel framework favorable for rapid ion transport in both its soft interfacial and bulk phases. The RMSPE exhibited excellent ion conductivity of 1.91 mS cm-1 at room temperature and a high Li+ transference number of 0.7. Assembled symmetrical Li cells realized stable cycling for over 2400 h at 3.0 mA cm-2. LiFePO4 full batteries demonstrated a long lifespan of 3300 cycles with a capacity retention of 93.5 % and stable cycling performance at -35 °C. This innovative design concept offers a promising perspective for achieving high-performance polymer-based Li metal batteries.

Advanced biomimetic design strategies for porous structures promoting bone integration with additive-manufactured Ti6Al4V scaffolds

The natural bone structure exhibits a radial gradient with dense cortical bone externally and porous cancellous bone internally. However, previous studies proposing scaffold designs have predominantly focused on homogeneous porous structures. Moreover, no consensus exists on the optimal structure for gradient porous scaffolds. Our scaffold closely imitated the natural bone structure by incorporating a gradient of pillar diameters. Additionally, we introduced a inverse gradient structure and three uniform diameter pillar structures (400 μm, 600 μm, and 1000 μm) for comparative analysis. Mechanical testing revealed that the compressive strength and elastic modulus of the Ti6Al4V porous scaffolds gradually increased with an increase in pillar diameter. In vitro experiments demonstrated that both the biomimetic gradient and inverse gradient scaffolds promoted osteogenic differentiation, with higher ALP activity (alkaline phosphatase) and osteogenesis-related gene expression compared to the uniform pillar structure scaffolds. The in vivo experiments confirmed these results, highlighting the superior ability of the biomimetic gradient Ti6Al4V porous scaffold to induce new bone formation. Based on our findings, we suggest that the optimal porous structure should have fine-diameter pillars (approximately 400 μm) internally to enhance cell penetration, while coarse-diameter pillars (approximately 800 μm) should be used externally to increase the cell attachment area and enhance mechanical strength. Overall, our study contributes to the field of bone tissue engineering by providing a biomimetic scaffold design that closely imitates the structure of natural bone and promotes osteogenic activity.

(Invited) Organic Electrochemical Bioelectronic Devices Based on 3D Conductive Polymer Scaffolds

The integration of 3D tissue-engineered microporous scaffolds based on conductive polymers (CPs) into bioelectronic devices have led to the possibility of dynamic monitoring of biological phenomena through electrical measurements. The 3D structure and morphology of the porous scaffolds mimics the topographical features of human physiology, while the electrically conductive nature of the polymers allows for electrical measurements for label-free monitoring and live-sensing of cells. 3D scaffolds based on the polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) prepared by the freeze drying process have been the focus of many studies and well integrated into bioelectronic devices such as electrodes[1] and organic electrochemical transistors[2].The influence of the different protocols and freezing rates on the pore size and structure was examined by scanning electron microscopy and micro computed tomography. Pores of circular and elongated ellipses were observed by SEM and a pore size distribution (the longest dimension of the ellipsoid) between 80 µm and 220 µm was measured. It was observed that a higher cooling rate generated larger pores with more elongated pore morphology as well as a wider pore size distribution. The pre-cooling treatment with 0.5°C/min cooling rate was most useful in generating scaffolds with a more homogenous pore structure and a pore size of approximately 100 µm.The different scaffolds were incorporated into electronic devices such as transmembrane electrodes to characterize the electrical properties and evaluate the reproducibility of the scaffolds prior to cell culture. No significant change in the electrochemical impedance spectra was observed despite the large difference in porosity of the different scaffolds. In addition, the different scaffolds were used to host and monitor biological cells like fibroblasts and endothelial cells. Cell growth and proliferation in the different scaffolds was also monitored by immunofluorescence microscopy. It was observed that a pre-cooling protocol and a freezing rate of 0.5°C/min helps to fabricate scaffolds with an optimized, uniform and homogenous pore morphology. This design protocol is highly beneficial in reducing the random artifacts of the nucleation process and generating scaffolds highly conducive to cell growth and survival and to create a versatile bioelectronic platform for studying in-vitro cell models.A new, sophisticated bioelectronic device was constructed with the scaffolds with the operation mode of an electrode and an organic electrochemical transistor. The device operation models an electrochemical cell with two or three electrodes and is used to build different in vitro organ models. In this presentation, I show the use of electrochemical techniques to monitor biological phenomenon based on 3D conducting polymer scaffolds.

Advancing Anode Performance in Aqueous Zinc-Ion Batteries: A Review of Metal-Organic Framework-Based Strategies.

Aqueous zinc-ion batteries (AZIBs) are garnering substantial research interest in electric vehicles, energy storage systems, and portable electronics, primarily for the reason that the inexpensive cost, high theoretical specific capacity, and environmental sustainability of zinc metal anodes, which are an essential component to their design. Nonetheless, the progress of AZIBs is hindered by significant obstacles, such as the occurrence of anodic side reactions (SR) and the formation of zinc dendrites. Metal-organic framework (MOF)-based materials are being explored as promising alternatives owing to homogeneous porous structure and large specific surface areas. There has been a rare overview and discussion on strategies for protecting anodes using MOF-based materials. This review specifically aims to investigate cutting-edge strategies for the design of highly stable MOF-based anodes in AZIBs. Firstly, the mechanisms of dendrites and SR are summarized. Secondly, the recent advances in MOF-based anodic protection including those of pristine MOFs, MOF composites, and MOF derivatives are reviewed. Furthermore, the strategies involving MOF-based materials for zinc anode stabilization are presented, including the engineering of surface coatings, three-dimensional zinc structures, artificial solid electrolyte interfaces, separators, and electrolytes. Finally, the ongoing challenges and prospective directions for further enhancement of MOF-based anodic protection technologies in AZIBs are highlighted.

Regulating pore structure of aramid nanofiber (ANF) separators for lithium–sulfur (Li–S) batteries

Excellent ionic conductivity and mechanical robustness are significant for separators of Li–S batteries. Aramid nanofiber (ANF) has been widely used in separators due to their excellent mechanical properties and high-temperature resistance. However, pure ANF separator possesses a dense pore structure resulting from the closely intertwined nanofibrous network, leading to inferior ionic conductivity. Herein, we propose a strategy of inhibiting of hydrogen bonding (IHB) among nanofibers to regulate the pore structure of ANF separators via employing pore-forming agent, solvation, and differentiated drying methods. Notably, a graph theoretical methodology (structural GT) is introduced to analyze the percolating network of ANF separator, revealing that the higher average nodal connectivity, the more abundant and homogeneous porous structure and higher conductivity. Excitingly, the pore size and the ionic conductivity of ANF separator by supercritical carbon dioxide drying (S-ANFs) is 44 nm and 0.171 mS/cm, which is 5 times and 1.9 times higher than pure ANF separator, respectively. Moreover, the ANF separator is dimensionally stable under 200 °C, demonstrating its desirable security under extreme conditions. Finally, the half-cell equipped resultant S-ANFs exhibits outstanding cycling stability (566 mAh/g after 200 cycles at 0.5 C) and Coulombic efficiency (99.25%). This work provides an efficient strategy to regulate the pore structure of ANF separator.

Osmotic pressure regulated sodium alginate-graphene oxide hydrogel as a draw agent in forward osmosis desalination

The freshwater shortage has become a global issue due to the population explosion. As an effective response to the water crisis, forward osmosis (FO) desalination technology is applied because of its comparatively low membrane fouling and low energy consumption. Hydrogels, as draw solutions in FO, have received increasing attention due to their properties of no reverse solute flux, and strong water recovery capability. However, the concentration in the feed solution is below 8000 ppm restricted by the lack of a clear mechanism for osmotic pressure regulation. In this work, a sodium alginate-graphene oxide (SA-GO) hydrogel was proposed with excellent performance in drawing water. The hydrogel has a homogeneous porous structure that enables easy water recovery through compression. When the SA-GO-1 hydrogel was used for the treatment of the simulated seawater (35,000 ppm NaCl solutions), the initial water flux achieved 0.4429 L m−2 h−1 (LMH), and the average water flux remained at 0.1783LMH. In contrast to conventional tactics, the osmotic pressure of hydrogel was regulated based on Flory-Rehner theory (FR). Moreover, the interaction energy was computed to reveal the mechanism of osmotic pressure regulation. This strategy provides a potential solution for the design of high-performance draw solutions for FO systems.

Effect of quince seed gum (QSG) on the performance of injectable hyaluronic acid hydrogels in terms of the rheological, morphological, and mechanical aspect.

Injectable hydrogels play an important role in tissue engineering as a filling and repairing material. This study aimed to develop a new injectable hydrogel based on hyaluronic acid (HA) and quince seed gum (QSG) and investigate the effect of QSG on hydrogel performance. The amount of unreacted 1,4-Butanediol diglycidyl ether is maintained at an undetectable level for HA-QSG hydrogels. Amino acid analysis showed that the HA-QSG hydrogel had rich amino acid concentrations of leucine, arginine, and valine. After thermal sterilization, the elastic modulus of HA-QSG gels for dermal and intraarticular filler applications is 63 Pa and 92 Pa, respectively. Pore size was found below 200 μm and the dense homogeneous pore structure was observed.

Sandy soil based foam concrete with ultra-small pore structure through in-situ mechanical frothing

During the manufacturing of foam concrete, conventional chemical and physical foaming methods are still inadequate for regulating and stabilizing the bubble properties. In this work, a one-pot method, denoted as in-situ mechanical frothing, was proposed preparing foam concrete by vigorously stirring the mixture of water, cement, sandy soil, and foaming agent. Sandy soil (SS) was used in the content range of 25–75 % as cement replacement to decrease the binder consumption and reduce costs. The influence of in-situ mechanical frothing technology and SS dosage on the properties of paste rheology, pore structure, compressive strength, and thermal properties was investigated. The results showed that the average pore size of foam concrete prepared by this method is between 45.73 and 74.58 μm. The compressive strength of the formed foam concrete at dry density of 600–1000 kg/cm3 was 2.78–16.37 MPa, which was 85%–231 % higher than that the standard values. The incorporation of SS resulted in smaller and homogeneous pore structure in foam concrete. Moreover, foam concrete with 25–75 % SS dosage showed 7–40 % decrease in thermal conductivity. The overall analysis showed that the 25–50 % SS-incorporated foam concrete enabled achieving higher standard properties through in-situ mechanical frothing.

Novel insights into intrinsic mechanisms of magnetic field on long-term performance of anaerobic ammonium oxidation process

The performance of an anaerobic ammonium oxidation (anammox) reactor with the magnetic field of 40 mT was systematically investigated. The total nitrogen removal rate was enhanced by 16% compared with that of the control group. The enhancing mechanism was elucidated from the improved mass transfer efficiency, the complicated symbiotic interspecific relationship and the improved levels of functional genes. The magnetic field promoted formation of the loose anammox granular sludge and the homogeneous and well-connected porous structure to enhance the mass transfer. Consequently, Candidatus Brocadia predominated in the sludge with an increase in abundance of 13%. Network analysis showed that the positive interactions between Candidatus Brocadia and heterotrophic bacteria were strengthened, which established a more complicated stable microbial community. Moreover, the magnetic field increased the levels of hdh by 26% and hzs by 35% to promote the nitrogen metabolic process. These results provided novel insights into the magnetic field-enhanced anammox process.

Photonic Pigments of Polystyrene-block-Polyvinylpyrrolidone Bottlebrush Block Copolymers via Sustainable Organized Spontaneous Emulsification.

Prior studies on photonic pigments of amphiphilic bottlebrush block copolymers (BBCPs) through an organized spontaneous emulsification (OSE) mechanism have been limited to using polyethylene glycol (PEG) as the hydrophilic side chains and toluene as the organic phase. Herein, a family of polystyrene-block-polyvinylpyrrolidone (PS-b-PVP) BBCPs are synthesized with PVP as the hydrophilic block. Biocompatible and sustainable anisole is employed for dissolving the obtained BBCPs followed by emulsification of the solutions in water. Subsequent evaporation of oil-in-water emulsion droplets triggers the OSE mechanism, producing thermodynamically stable water-in-oil-in-water (w/o/w) multiple emulsions with uniform and closely packed internal droplet arrays through the assembly of the BBCPs at the w/o interface. Upon solidification, the homogeneous porous structures are formed within the photonic microparticles that exhibit visible structural colors. The pore diameter is widely tunable (150∼314 nm) by changing the degree of polymerization of BBCP (69∼110), resulting in tunable colors across the whole visible spectrum. This work demonstrates useful knowledge that OSE can be generally used in the fabrication of ordered porous materials with tunable internal functional groups, not only for photonic applications, but also offers a potential platform for catalysis, sensing, separation, encapsulation, etc.

TENOFOVIR DISOPROXIL FUMARATE RELEASE FROM GLUTARALDEHYDE CROSS-LINKED CHITOSAN/Β-CYCLODEXTRIN HYDROGEL

In this study, chitosan was produced from crayfish Astacus leptodactylus, and then it was used to synthesize chitosan-graft-β-cyclodextrin (CS-g-β-CD) hydrogel. The produced chitosan (CS) and the sythesized CS-g-β-CD hydrogel were characterized using a Fourier Transform Infrared Spectroscopy (FTIR), Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). Tenofovir disoproxil fumarate (TDF) was used as a model to investigate the antiviral drug release properties of the CS-g-β-CD hydrogel. The synthesized hydrogel had an almost homogeneous pore structure and a high swelling capacity which increases depending on the amount of β-Cyclodextrin (β-CD). The drug-loaded CS-g-β-CD hydrogels was examined by XRD and 1H-NMR, and SEM analyses. Seventy-three percent of the TDF loaded on the synthesized hydrogels was released into phosphate-buffered saline (PBS) solution at 37 ºC. The drug release behavior of all prepared CS-g-β-CD hydrogels fitted the Korsmeyer-Peppas model. The addition of β-CD into the gel improved the swelling ability and TDF release of the CS-g-β-CD hydrogel system.