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Spent coffee grounds (SCGs) are waste residues arising from the process of coffee brewing and are usually sent to landfills, causing environmental concerns. SCGs contain a considerable amount of fatty acids and is therefore a promising green alternative bio-based phase change material (PCMs) compared to conventional organic and inorganic PCMs. In this study, the extraction of coffee oil from SCGs was conducted using three different organic solvents-ethanol, acetone, and hexane. The chemical composition, chemical, and thermophysical properties of these coffee oil extracts were studied to evaluate their feasibility as a bio-based PCM. Gas chromatography-mass spectroscopy (GC-MS) analysis indicated that coffee oil contains about 60-80 % of fatty acids while the phase transition temperature of the coffee oil extracts is approximately 4.5 ± 0.72 °C, with latent heat values of 51.15 ± 1.46 J/g as determined by differential scanning calorimetry (DSC). Fourier Transform Infrared Spectroscopy (FTIR) and DSC results of coffee oil extracts after thermal cycling revealed good thermal and chemical stability. An application study to evaluate coffee oil extract as a potential cold therapy modality showed that it can maintain temperatures below normal body temperature for up to 46 min. In conclusion, this work exemplifies the potential of SCGs as a promising green and sustainable resource for bio-based PCMs for low-temperature thermal energy storage applications such as cold-chain transportation and cold therapy.

Aggregation of organic photothermal agents enhances their photothermal effect.

MYH9 encodes the heavy chain of nonmuscle myosin IIA, a ubiquitously expressed cytoplasmic myosin that regulates the actin cytoskeleton, cell migration, cell polarization, and signal transduction in cancer cells. Here, we investigated the role of MYH9 in cancer stem cells (CSCs) associated with esophageal cancer (EC). The subcellular localization of MYH9 was investigated in SKGT-4 cells through immunofluorescent analysis. MYH9+ and MYH9- spheroid cells were derived from SKGT-4 cells by flow cytometry and compared for self-renewal capacity, tumorigenicity, CD133 positivity, cisplatin resistance, and phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) activity. MYH9 messenger RNA expression was assessed in 30 EC patients by quantitative reverse transcription-polymerase chain reaction. Kaplan-Meier curves were plotted to explore the influence of MYH9 on EC survival. MYH9 localized to the plasma membrane, cytoplasm, and nucleus of SKGT-4 cells. Spheroid cells displayed higher MYH9 expression and positivity compared to parental SKGT-4 cells. MYH9+ cells showed strong CSC characteristics, including in vivo tumorigenicity, migration, invasion, cisplatin resistance, and CD133+ positivity. MYH9 activated the PI3K/AKT/mTOR axis in CSCs and was upregulated in EC patients with poor survival. Collectively, these data show that MYH9 significantly promotes tumorigenesis by regulating PI3K/AKT/mTOR signaling in EC. MYH9 expression remarkably correlates with poor prognosis and represents a novel biomarker and drug target for the diagnosis and treatment of EC.

Lignin is a versatile biomass that possesses many different desirable properties such as antioxidant, antibacterial, anti-UV, and good biocompatibility. Natural lignin can be processed through several chemical processes. The processed lignin can be modified into functionalized lignin through chemical modifications to develop and enhance biomaterials. Thus, lignin is one of the prime candidate for various biomaterial applications such as drug and gene delivery, biosensors, bioimaging, 3D printing, tissue engineering, and dietary supplement additive. This review presents the potential of developing and utilizing lignin in the outlook of new and sustainable biomaterials. Thereafter, we also discuss on the challenges and outlook of utilizing lignin as a biomaterial., Graphical abstract Image 1, Highlights • Lignin's antioxidant, antibacterial, anti-UV and biocompatibility properties can be harnessed. • Modification and functionalization of lignin allows synthesis of enhanced biomaterials. • Biomedical applications of lignin-derived biomaterials include drug and gene delivery, biosensors, and tissue engineering.

Flexible electronics is an emerging field of research involving multiple disciplines, which include but not limited to physics, chemistry, materials science, electronic engineering, and biology. However, the broad applications of flexible electronics are still restricted due to several limitations, including high Young's modulus, poor biocompatibility, and poor responsiveness. Innovative materials aiming for overcoming these drawbacks and boost its practical application is highly desirable. Hydrogel is a class of 3D crosslinked hydrated polymer networks, and its exceptional material properties render it a promising candidate for the next generation of flexible electronics. Here, we review the latest methods of synthesizing advanced functional hydrogels and the state-of-art applications of hydrogel-based flexible electronics in various fields. More importantly, we discuss on the correlation between properties of the hydrogel and device performance, to have better understanding of the development of flexible electronics by using environmentally responsive hydrogels. Lastly, we provide perspectives on the current challenges and future directions in the development of hydrogel-based multifunctional flexible electronics. This article is protected by copyright. All rights reserved.

Microencapsulated phase change materials (MEPCMs) are effective solutions for addressing the issue of leakage that phase change materials (PCMs) face in thermal energy storage devices. Their applications are ubiquitous as PCMs are utilized in industries such as logistics, construction, electronics, etc., thus, an efficient method to prevent problems such as leakage and poor thermal conductivity is to encapsulate the PCM which not only renders it leakage-proof but also impart mechanical strength and enhanced thermal properties. The application of silicon-based additives is one of the most studied methods to impart such desired properties. We discuss the silicon-containing compounds which are commonly employed in core-shell matrix of encapsulated PCMs, namely, siloxanes and silicone, silicon nitride, silicon carbide, silica/SiO2, and other silicon-containing additives as they are able to provide synergistic improvements and exhibit enhanced physical properties. In this review, the different silicon compounds used as additives or main shell matrix are discussed, the general fabrication of the MEPCM and its thermophysical properties will be briefly highlighted. Lastly, we also examine its application and performance in thermal storage and thermal management. We hope to provide a broader perspective of silicon-containing MEPCM for those who are working in the similar field of research.

SQR29 organophotosensitizer was encapsulated into poly(lignin/PEG/PPG urethane) to form a hydrogel (LSQR29), providing excellent antibacterial photodynamic therapy (aPDT) property to combat antibiotic-resistant pathogenic bacteria in wound infection.

The rise of antimicrobial-resistant bacteria strains has been a global public health concern due to their ability to cause increased patient morbidity and a greater burden on the healthcare system. As one of the potential solutions to overcome such bacterial infections, hyperbranched copolymers with cationic charges were developed. These copolymers were assessed for their antimicrobial efficacy and their bactericidal mechanisms. They were found to be potent against mobile colistin-resistant 1 strains, which was significant as colistin is known to be the last-resort antibiotic against Gram-negative bacteria. Furthermore, there was no sign of mutational resistance developed by E. Coli ATCC 25922 and MCR 1+ E. Coli against the copolymer even up to 20 passages. The ability to evade inducing resistance would provide invaluable insights for future antibiotic development. Our studies suggest that the bactericidal efficacy comes from the ability to target the outer membrane efficaciously. In vivo study using a Pseudomonas keratitis model showed that the copolymer was compatible with the eye and further supported that the copolymer treatment was effective for complete bacteria elimination.

There has been increasing exploration of the development and production of biodegradable polymers in response to issues with petrol-based polymers and their impact on the environment. Here we report a new approach to synthesize a natural nanogel from lignin and nanocellulose. First, lignin nanobeads were synthesized by a solvent-shifting method, which showed a spherical shape with a diameter of 159.7 nm. Then the lignin nanobeads were incorporated into a nanocellulose network to form the lignin/cellulose nanogels. The nanocellulose fibrils (CNF-C) nanogels reveal a higher storage modulus than the nanocellulose crystal (CNC-C) ones due to the denser network with self-entanglement of longer cellulose chains. The presence of lignin nanobeads in the nanogels helped to increase the viscoelasticity of the nanogels. This work highlights that the new kinds of green nanogels could be potentially utilized in a variety of biomedical applications such as drug delivery and wound dressing.

Supramolecular hydrogels have attracted considerable interest due to their unique stimuli-responsive and self-healing properties. However, these hydrogel systems are usually achieved by covalent grafting of supramolecular units onto the polymer backbone, which in turn limits their reprocessability. Herein, we prepared a supramolecular hydrogel system by forming dynamic covalent crosslinks between 4-carboxyphenylboronic acid (CPBA) and polyvinyl alcohol (PVA). The system was then further crosslinked with either calcium ions or branched polyethylenimine (PEI) to generate hydrogels with distinctly different properties. Incorporation of calcium ions resulted in the formation of hydrogels with higher storage modulus of 7290 Pa but without self-healing properties. On the other hand, PEI-crosslinked hydrogel (PVA-CPBA-PEI) exhibited2000% critical strain value, demonstrated high stability over 52 days and showed sustained antibacterial effect. A combination of supramolecular interactions and dynamic covalent crosslinks can be an alternate strategy to fabricate next-generation hydrogel materials.

A high prevalence of middle one-third clavicle fracture has been reported. Both superior and anterior clavicle plates have been used in clinical and biomechanical research, but no decisive advantage for either design has been reported. Spiral clavicle plates have not been well studied in terms of their structural stability and implant safety. The present study analyses the multi-directional biomechanical performance of spiral clavicle plates using the finite element method. Two commercial spiral clavicle plate designs were reconstructed to simulate the surgical reduction of a middle one-third oblique clavicle fracture (OTA classification: 15-B1.2). Mechanical load, including axial compression, inferior bending, and axial torsion, was applied to evaluate the multi-directional structural stability and implant safety of the plates. The two spiral clavicle plate designs enhanced structural stiffness under axial compression, inferior bending, and axial torsion by 59–71%, 38–82%, and 31–46%, respectively, compared to that of the intact clavicle model. Stress concentrations were found around the reconstruction feature of the plate and the screw hole, especially under inferior bending. The improvement in multi-directional biomechanical stability provided by a spiral clavicle plate is worth considering in clinical applications. Implant safety should be further investigated based on mechanical tests and clinical observations.

Iron oxide nanomaterials with mimic enzymes activity have been paid more attention in the clinical diagnosis field. The modified surface molecules would influence the catalytic activity of nanozyme, which is worth studying. Furthermore, the traditional detection strategy is based on colorimetric change of substrates, however, the optical signal is easy to be interfered in complex biological applications. In our research, an efficient and facile preparation strategy was developed to obtain functional artificial nanozymes. Herein, three kinds of surfactants, including citrate acid, poly(ethylene glycol) bis (carboxymethyl) ether and tannic acid have been applied to modify these nanomaterials that showed uniform size, high soluble dispersity and stability. Furthermore, these nanozymes exhibited different peroxidase-like activity to catalyze the hydrogen peroxide and 3,3′,5,5′-tetramethylbenzidine. More importantly, magnetic relaxation effect of iron oxide nanozymes was found to be changed during the catalytic reaction. In addition, the relationship between the magnetic signal of nanozymes and the substrate concentration showed a good linear dependence. Combined with the natural enzymes, the magnetic detection of iron oxide nanozymes also exhibited excellent substrate specificity. On these bases, a dual-function specific assay was constructed and further used for glucose detection. In conclusion, this study demonstrated an efficient iron oxide nanozymes preparation method and constructed a new synergistically colorimetric-magnetic diagnosis strategy.

The cathode materials for sodium ion batteries (SIBs) are intrinsically unstable due to their oxidation by electrolyte solution at high voltage; thus, developing novel solid permeable interfaces as passivation layers is critical to avoid these side oxidation reactions and increase the cycling durability of SIBs. Nevertheless, the abuse of passivation layers can hinder the Na+ transfer and further impact the rate capability. Herein, we demonstrated an effective approach that utilized konjac glucomannan (KGM) biopolymer as a multifunctional binder to build stable solid permeable interface films to achieve high-performance for Na3V2(PO4)3/C (NVP) cathodes. Compared with polyvinylidene difluoride (PVDF), the strong adhesion and solid permeable interface films of KGM protect the integrity of the electrodes. The unique conductive network and rich polar functional groups enable KGM to enhance the transfer of electrons and Na+ ions at the interfaces. Thanks to the multiple functions of KGM offering adhesion strength, a conductive network and a solid permeable interface, the NVP cathode exhibited a reversible capacity of 108.0 mA h g−1 at 0.5C (1C = 117 mA g−1). At a high rate of 50C, NVP profited from KGM to show a good capacity of 63.1 mA h g−1 and a high durability of 10 000 cycles with a small fading rate of 0.00259% per cycle. Hard carbon‖NVP full batteries, using KGM as the cathode binder, possessed a high specific energy of 137.7 W h kg−1, indicating the potential applications of KGM as an environmentally friendly binder for achieving high-rate capacity and long-term cycling durability of SIBs.

Dealing with the aftermath of a disastrous oil spill proves to be challenging with the current remedies as it poses issues of secondary pollution, low oil recovery, and non-biodegradability. Hereby...

Eco-friendly superhydrophobic polycaprolactone (PCL) membranes with hierarchical structure for efficient oil/water separation were fabricated via a simple and practical route. First, a series of hi...

Background: Rheumatoid arthritis (RA) is a chronic disabling inflammatory disease that causes synovial angiogenesis in an invasive manner and leads to joint destruction. Currently available pharmacotherapy for RA has unwanted side effects and limitations. Although anti-angiogenic therapy is regarded as a new potential treatment for RA, only a few anti-angiogenic drugs are available. An increasing number of studies have shown that β-sitosterol (BSS) may exert inhibitory effects against angiogenesis. However, the mechanisms involved are still unclear.Methods: Based on the results of the gene set enrichment analysis (GSEA) of the transcriptome data of endothelial cells from RA patients, we evaluated the pharmacological effects of BSS on the tube formation, cell proliferation, and migration of human umbilical vein endothelial cells (HUVECs). Furthermore, the effects of BSS treatment on vascular endothelial growth factor receptor 2 (VEGFR2) were determined using molecular docking and Western blotting. Additionally, in the presence or absence of BSS, synovial angiogenesis and joint destruction of the ankle were investigated in collagen-induced arthritis (CIA) mice. The effect of BSS treatment on VEGFR2/p-VEGFR2 expression was verified through immunohistochemical staining.Results: The immunohistochemistry results revealed that BSS treatment inhibited angiogenesis both in vitro and in vivo. In addition, the results of 5-ethynyl-2′-deoxyuridine and cell cycle analysis showed that BSS treatment suppressed the proliferation of HUVECs, while the Transwell migration and stress fiber assays demonstrated that BSS treatment inhibited the migration of HUVECs. Notably, the inhibitory effect of BSS treatment on VEGFR2/p-VEGFR2 was similar to that of axitinib. In CIA mice, BSS also exerted therapeutic effects on the ankles by reducing the degree of swelling, ameliorating bone and cartilage damage, preventing synovial angiogenesis, and inhibiting VEGFR2 and p-VEGFR2 expression.Conclusion: Therefore, our findings demonstrate that BSS exerts an inhibitory effect on synovial angiogenesis by suppressing the proliferation and migration of endothelial cells, thereby alleviating joint swelling and bone destruction in CIA mice. Furthermore, the underlying therapeutic mechanisms may involve the inhibition of VEGF signaling pathway activation.

Oxidative phosphorylation is an important biological process in the body to produce energy, during which oxygen free radicals are generated as byproduct. Excessive oxygen free radicals cause cell death and reduce the rate of tissue regeneration and healing in a wound. Lignin is a natural antioxidant derived from plants, but its biomedical application is restricted because of the uncertain biocompatibility. In this work, we developed a lignin-incorporated nanogel and explored its application for wound healing. Lignin was extracted from coconut husks and determined to have strong antioxidant activity (IC