A Maitake (Grifola frondosa) polysaccharide ameliorates Alzheimer's disease-like pathology and cognitive impairments by enhancing microglial amyloid-β clearanceBai, Yao; Chen, Lingling; Chen, Yao; Chen, Xinmeng; Dong, Yilong; Zheng, Shangyong; Zhang, Lei; Li, Weiyuan; Du, Jing; Li, Hongliang
doi: 10.1039/c9ra08245jpmid: 35542273
Alzheimer's disease (AD) is characterized by the deposition of amyloid-β (Aβ) plaques, neuronal loss and neurofibrillary tangles. In addition, neuroinflammatory processes are thought to contribute to AD pathophysiology. Maitake (Grifola frondosa), an edible/medicinal mushroom, exhibits high nutritional value and contains a great amount of health-beneficial, bioactive compounds. It has been reported that proteo-β-glucan, a polysaccharide derived from Maitake (PGM), possesses strong immunomodulatory activities. However, whether PGM is responsible for the immunomodulatory and neuroprotection effects on APPswe/PS1ΔE9 (APP/PS1) transgenic mice, a widely used animal model of AD, remains unclear. In the present study, the results demonstrated that PGM could improve learning and memory impairment, attenuate neuron loss and histopathological abnormalities in APP/PS1 mice. In addition, PGM treatment could activate microglia and astrocytes and promote microglial recruitment to the Aβ plaques. Also, PGM could enhance Aβ phagocytosis, and thereby alleviate Aβ burden and the pathological changes in the cortex and hippocampus in APP/PS1 mice. Moreover, PGM showed no significant effect on mice body weight. In conclusion, these findings indicated that administration of PGM could improve memory impairment via immunomodulatory action, and dietary supplementation with PGM may provide potential benefits on brain aging related memory dysfunction.
Synthesis and characterisation of fluorinated epitaxial films of BaFeO2F: tailoring magnetic anisotropy via a lowering of tetragonal distortionNair, Akash; Wollstadt, Stephan; Witte, Ralf; Dasgupta, Supratik; Kehne, Philipp; Alff, Lambert; Komissinskiy, Philipp; Clemens, Oliver
doi: 10.1039/c9ra08039bpmid: 35542307
In this article, we report on the synthesis and characterisation of fluorinated epitaxial films of BaFeO2F via low-temperature fluorination of thin films of BaFeO2.5+d grown by pulsed laser deposition. Diffraction measurements show that fluoride incorporation only results in a contraction of the film perpendicular to the film surface, where clamping by the substrate is prohibitive for strong in-plane changes. The fluorinated films were found to be homogenous regarding the fluorine content over the whole film thickness, and can be considered as single crystal equivalents to the bulk phase BaFeO2F. Surprisingly, fluorination resulted in the change of the tetragonal distortion to a nearly cubic symmetry, which results in a lowering of anisotropic orientation of the magnetic moments of the antiferromagnetically ordered compound, confirmed by Mössbauer spectroscopy and magnetic studies.
Remote loading of curcumin-in-modified β-cyclodextrins into liposomes using a transmembrane pH gradientOdeh, Fadwa; Nsairat, Hamdi; Alshaer, Walhan; Alsotari, Shrouq; Buqaien, Rula; Ismail, Said; Awidi, Abdalla; Al Bawab, Abeer
doi: 10.1039/c9ra07560gpmid: 35542296
Curcumin (CRM) is a natural polyphenol with antioxidative, anti-inflammatory, and anticancer therapeutic properties. However, CRM therapeutic potential is limited by low water solubility and bioavailability. Intraliposomal remote loading describes the retention of drugs in liposome cores in response to transmembrane pH gradient. The current study describes for the first time the remote loading of CRM into liposomes using secondary (E-βCD) and tertiary (D-βCD) amino-modified β-cyclodextrins (βCDs) as carriers and solubilizers. βCDs were chemically modified to prepare the ionizable weak base functional group followed by forming a guest-host complex of CRM in the modified βCDs hydrophobic cavities via a solvent evaporation encapsulation technique. These complexes were then actively loaded into preformed liposomes, composed of DPPC/cholesterol (65/35 molar ratio) via pH gradient. The formation of CRM-βCDs inclusion complexes was characterized using UV-Vis spectroscopy, thermal analysis, and NMR spectroscopy. The complex stoichiometric ratio was determined to be 1 : 1 of CRM-βCDs based on Job's plot which was also confirmed by the modified Benesi–Hildebrand equation with increasing probability of forming the 1 : 2 ratio of CRM-βCDs. The apparent formation constants (Kf) of 51.6, 100.9 and 55.4 mM−2 were determined for CRM-βCD, CRM-E-βCD, and CRM-D-βCD complexes, respectively. Liposome size, charge and polydispersity index indicate the presence of a homogeneous population before and after active loading. The encapsulation efficiencies of CRM-βCD complexes into pH gradient preformed liposomes were 16.5, 51.1, and 41.7 for CRM-βCD, CRM-E-βCD, and CRM-D-βCD, respectively, showing more than 5 fold increase compared to normal liposomes. The current study provides a novel remote loading approach utilizing chemically modified cyclodextrins to incorporate hydrophobic drugs into liposomes.
Synthesis of Bi2O3/g-C3N4 for enhanced photocatalytic CO2 reduction with a Z-scheme mechanismPeng, Hao; Guo, Rui-Tang; Lin, He; Liu, Xing-Yu
doi: 10.1039/c9ra07485fpmid: 35542275
Bi2O3/g-C3N4 nanoscale composites with a Z-scheme mechanism were successfully synthesized by high temperature calcination combined with a hydrothermal method. These synthesized composites exhibited excellent photocatalytic performance, especially the 40 wt% Bi2O3/g-C3N4 composite, which produced about 1.8 times the CO yield of pure g-C3N4. The obtained products were characterized by X-ray diffraction (XRD) patterns, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), UV-vis diffuse reflectance spectroscopy (UV-vis DRS) and so on. Characterization results revealed that Bi ions had well covered the surface of g-C3N4, thus restraining the recombination of electron–hole pairs and resulting in a stronger visible-light response and higher CO yield. In addition, the electron transfer process through the Z-scheme mechanism also promoted the photocatalytic activity.
N, O and P co-doped honeycomb-like hierarchical porous carbon derived from Sophora japonica for high performance supercapacitorsZhang, Li; Zhu, Yuxia; Zhao, Guangzhen; Li, Yanjiang; Zhu, Guang
doi: 10.1039/c9ra06934hpmid: 35542269
Novel N, O and P co-doped honeycomb-like hierarchically porous carbon (N-O-P-HHPC) materials with a large specific surface area from Sophora japonica were prepared via a one-step activation and carbonization method and used as an electrode for supercapacitors. The results indicate that as-prepared N-P-HHPC with a large specific surface area (2068.9 m2 g−1) and N (1.5 atomic%), O (8.4 atomic%) and P (0.4 atomic%) co-doping has a high specific capacitance of 386 F g−1 at 1 A g−1. Moreover, a 1.8 V symmetrical SC was assembled from the N-O-P-HHPC-3 electrode using 1 M Na2SO4 gel electrolyte, presenting a high energy density (28.4 W h kg−1 at 449.9 W kg−1) and a long life cycling stability with only 7.3% capacitance loss after 10 000 cycles. Furthermore, the coin-type symmetrical SC using EMIMBF4 as electrolyte presents an ultrahigh energy density (80.8 W h kg−1 at 1500 W kg−1). When the two coin-type symmetrical SCs are connected in series, eight red light-emitting diodes (LEDs) and a small display screen can be powered. These results demonstrate as-prepared N, O and P co-doped HHPC is a considerable candidate as a carbon electrode for energy storage devices.
P3HT-based visible-light organic photodetectors using PEI/PAA multilayers as a p-type buffer layerJi, Chan Hyuk; Lee, Seon Ju; Oh, Se Young
doi: 10.1039/c9ra08568hpmid: 35542281
A low leakage current is critical for achieving organic photodetectors (OPDs) with high detectivity. The insertion of buffer layers is an effective approach for reducing the reverse-biased leakage current. In this study, polyelectrolyte multilayers comprising polyethyleneimine (PEI) and polyacrylic acid (PAA) were introduced by a spin-assisted layer-by-layer technique into an OPD as a p-type buffer layer. Although PEI/PAA multilayers are insulators, when used as a buffer layer in our device, they suppressed the leakage current and also provided a high photocurrent due to the light-assisted tunneling effect. The prepared device configuration was ITO/(PEI/PAA)2/P3HT:PC60BM/Yb/Al. The performances of the OPDs were investigated by measuring the current–voltage characteristics, external quantum efficiency, and transient photocurrent. In addition, the operating mechanism of the OPDs was confirmed by impedance analysis. The device comprising (PEI/PAA)2 showed a specific detectivity of 3.11 × 1012 Jones and a bandwidth of 103.2 kHz at −1 V and 525 nm. This performance is a numerical value that can be used in devices such as a line scan camera. In addition, because this device is fabricated by a low-temperature solution process, flexible and large-area substrates can be used.
Study on photoelectric characteristics of monolayer WS2 filmsWang, Lin; Wang, Wenyan; Wang, Quan; Chi, Xiaochun; Kang, Zhihui; Zhou, Qiang; Pan, Lingyun; Zhang, Hanzhuang; Wang, Yinghui
doi: 10.1039/c9ra07924fpmid: 35542289
It is important to determine the time-dependent evolution of the excited monolayer WS2, which will provide a basis for the reasonable design of optoelectronic devices based on two-dimensional transition metal dichalcogenides. Here, we made a simple and large-area photodetector based on the monolayer WS2, with high light sensitivity and fast response, benefiting from the special dynamics of carrier involving the exciton, trion, and charge. Moreover, we tested the relaxation behavior of the excited monolayer WS2 by employing transient absorption (TA). It was found that the multi-body interaction among exciton would occur after the density of pump photon increases to 3.45 × 1014 photons per cm2. The exciton dissociation accompanying the generation of trion would appear in the photo-induced relaxation process, which would be a benefit for the operation of this photodetector. Increasing the energy of the exciton is good for the generation of carrier by comparing the relaxation behavior of WS2 excited to A and B exciton states. However, the bound exciton relaxation, originating from the capture process of the defect state, would exist and play an unfavorable role during the functioning of devices.