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Nanofluorescent material is developing rapidly as a new type of material. Nanofluorescent probes have broad application prospects in biological analysis, drug metabolism, and semiconductor optical materials. Chitosan is non-toxic and rich in nature which has good biocompatibility, and it can be combined with fluorescent probes. Therefore, the preparation and application of Nanofluorescent probes using chitosan as a carrier is summarized in this article. Fluorescent probes can be combined with other different materials through different reaction mechanisms, and the prepared composite materials can be widely used in biomaterials, sewage treatment, medicine and other fields., Competing Interests: Declaration of competing interest There are no conflicts to declare., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In order to improve the bioavailability of Juglans regia L. polyphenols (JRP) in human body, the novel Juglans regia L. polyphenols-Hohenbuehelia serotina polysaccharides (HSP) nanoparticles (JRP-HSP NPs) were synthesized based on electrostatic interaction. Moreover, the physicochemical properties, morphologies and gastrointestinal digestive characteristics of JRP-HSP NPs were respectively measured and analyzed. Among four kinds of JRP-HSP NPs prepared by different condition of mass ratio, JRP-HSP NPs (1:16) with encapsulation efficiency of 51.62%, average particle size of 341.0 nm, and zeta potential of -29.3 mv, presented better physicochemical properties, such as thermal stability, photostability and crystalline properties. Morphological analysis revealed JRP-HSP NPs (1:16) appeared spherical and almost uniform. Through evaluation of simulated gastrointestinal digestion, JRP-HSP NPs prevented the variation of phenolic composition induced by gastrointestinal digestion, which was similar as the one of undigested JRP, while un-encapsulated JRP exhibited totally different state due to degradation and biotransformation, suggesting that JRP-HSP NPs possessed the sustained release characteristics in gastrointestinal system. This study provided a non-toxic strategy to encapsulate polyphenols for improving their bioavailability., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Purpose: Lecithin/chitosan nanoparticles have shown great promise in the transdermal delivery of therapeutic agents. Baicalein, a natural bioactive flavonoid, possesses multiple biological activities against dermatosis. However, its topical application is limited due to its inherently poor hydrophilicity and lipophilicity. In this study, the baicalein-phospholipid complex was prepared to enhance the lipophilicity of baicalein and then lecithin/chitosan nanoparticles loaded with the baicalein-phospholipid complex were developed to improve the transdermal retention and permeability of baicalein., Methods: Lecithin/chitosan nanoparticles were prepared by the solvent-injection method and characterized in terms of particle size distribution, zeta potential, and morphology. The in vitro release, the ex vivo and in vivo permeation studies, and safety evaluation of lecithin/chitosan nanoparticles were performed to evaluate the effectiveness in enhancing transdermal retention and permeability of baicalein., Results: The lecithin/chitosan nanoparticles obtained by the self-assembled interaction of chitosan and lecithin not only efficiently encapsulated the drug with high entrapment efficiency (84.5%) but also provided sustained release of baicalein without initial burst release. Importantly, analysis of the permeation profile ex vivo and in vivo demonstrated that lecithin/chitosan nanoparticles prolonged the retention of baicalein in the skin and efficiently penetrated the barrier of stratum corneum without displaying skin irritation., Conclusion: These results indicate the potential of drug-phospholipid complexes in enhancing the entrapment efficiency and self-assembled lecithin/chitosan nanoparticles based on phospholipid complexes in the design of a rational transdermal delivery platform to improve the efficiency of transdermal therapy by enhancing its percutaneous retention and penetration in the skin., Competing Interests: The authors report no conflicts of interest for this work., (© 2020 Dong et al.)

Background: Nanoparticles conjugated with fluorescent probes have versatile applications, serving not only for targeted fluorescent imaging but also for evaluating the in vivo profiles of designed nanoparticles. However, the relationship between fluorophore density and nanoparticle behavior remains unexplored. Methods: The IR783-modified liposomes (IR783-sLip) were prepared through a modified ethanol injection and extrusion method. The cellular uptake efficiency of IR783-sLip was characterized by flow cytometry and fluorescence microscope imaging. The effects of IR783 density on liposomal in vivo behavior were investigated by pharmacokinetic studies, biodistribution studies, and in vivo imaging. The constitution of protein corona was analyzed by the Western blot assay. Results: Dense IR783 modification improved cellular uptake of liposomes in vitro but hindered their blood retention and tumor imaging performance in vivo. We found a correlation between IR783 density and protein corona absorption, particularly IgM, which significantly impacted the liposome performance. Meanwhile, we observed that increasing IR783 density did not consistently improve the effectiveness of tumor imaging. Conclusions: Increasing the density of modified IR783 on liposomes is not always beneficial for tumor near-infrared (NIR) imaging yield. It is not advisable to prematurely evaluate novel nanomaterials through fluorescence dye conjugation without carefully optimizing the density of the modifications. [ABSTRACT FROM AUTHOR]

In recent years, quercetin plays an increasingly important role in the medical field. However, the absorption and effect of quercetin as a drug in vivo are limited due to its extremely poor solubility in water. In addition, chitosan nanoparticles can deliver poorly soluble drugs as drug delivery carriers. Herein, chitosan nanoparticles were prepared by oxidative degradation and ionic cross-linking technology to study the drug loading properties of quercetin. On the other hand, the application of chitosan for fluorescent materials can improve the biocompatibility of fluorescent materials and increase the adsorption of fluorescent materials. Fluorescently labeled chitosan nanoparticles, especially chitosan microsphere fluorescent probes prepared using the abundant amino groups on chitosan chains to react with fluorescein isothiocyanate (FTIC), have been widely used as fluorescent probes in biomarkers and medical diagnostics. Therefore, chitosan–quercetin (CS–QT) drug-loaded nanoparticles are labeled with FITC, and the drug-loaded rate, encapsulation efficiency, and antioxidant properties were investigated. The drug-loaded rate of the sample reaches 8.39%, the encapsulation rate reaches 83.65%, and exhibits good antioxidant capacity. The fluorescence aperture of the obtained sample was consistent with the inhibition zone, which could realize the visualization of the antibacterial performance of the sample. The fluorescent-labeled nano-system exhibit superior antibacterial properties, which provide a strategy for observing the release and function of drugs. [ABSTRACT FROM AUTHOR]

Abstract: The photoelectrochemical (PEC) water‐splitting efficiency of a hematite‐based photoanode is still far from the theoretical value due to its poor surface reaction kinetics and high density of surface trapping states. To solve these drawbacks, a photoanode consisting of NiO nanoparticles anchored on a gradient phosphorus‐doped α‐Fe2O3 nanorod (NR) array (NiO/P‐α‐Fe2O3) was fabricated to achieve optimal light absorption and charge separation, as well as rapid surface reaction kinetics. Specifically, a photoanode with the NR array structure allowed a high mass‐transport rate to be achieved, while phosphorus doping effectively decreased the number of surface trapping sites and improved the electrical conductivity of α‐Fe2O3. Furthermore, the p–n junction that forms between NiO and P‐α‐Fe2O3 can further improve the PEC performance due to efficient hole extraction and the water oxidization catalytic activity of NiO. Consequently, the NiO/P‐α‐Fe2O3 NR photoanode produced a high photocurrent density of 2.08 mA cm−2 at 1.23 V versus a reversible hydrogen electrode and a 110 mV cathodic shift of the onset potential. This rational design of structure offers a new perspective in exploring high‐performance PEC photoanodes. [ABSTRACT FROM AUTHOR]

13a-(S)-3-pivaloyloxyl-6,7-dimethoxyphenanthro(9,10-b)-indolizidine (CAT3) is a novel oral anti-glioma pro-drug with a potent anti-tumor effect against temozolomide-resistant glioma in vivo. However, poor lipid solubility has limited the encapsulation efficacy during formulation development. Moreover, although the active metabolite of CAT3, 13a(S)-3-hydroxyl-6,7-dimethoxyphenanthro(9,10-b)-indolizidine (PF403), can penetrate the blood-brain barrier and approach the brain tissue with a 1000-fold higher anti-glioma activity than CAT3 in vitro, its bioavailability and Cmax were considerably low in plasma, limiting the anti-tumor efficacy. In this study, a novel oleic acid-CAT3 conjugate (OA-CAT3) was synthesized at the first time to increase the lipid solubility of CAT3. The OA-CAT3 loaded solid lipid nanoparticles (OA-CAT3-SLN) were constructed using an ultrasonic technique to enhance the bioavailability and Cmax of PF403 in plasma. Our results demonstrated that CAT3 was amorphous in the lipid core of OA-CAT3-SLN and the in vitro release was well controlled. Furthermore, the encapsulation efficacy and the zeta potential increased to 80.65 ± 6.79% and −26.7 ± 0.46 mV, respectively, compared to the normal CAT3 loaded SLN. As indicated by the high-performance liquid chromatography-mass spectrometry (HPLC-MS/MS) quantitation, the monolayer cellular transepithelial transport rate of OA-CAT3-SLN improved by 2.42-fold relied on cholesterol compared to the CAT3 suspension. Hence, the in vitro cell viability of OA-CAT3-SLN in C6 glioma cells decreased to 29.77% ± 2.13% and 10.75% ± 3.12% at 48 and 72 h, respectively. Finally, compared to the CAT3 suspension, the in vivo pharmacokinetics in rats indicated that the plasma bioavailability and Cmax of PF403 as afforded by OA-CAT3-SLN increased by 1.7- and 5.5-fold, respectively. Overall, the results indicate that OA-CAT3-SLN could be an efficacious delivery system in the treatment of glioma. [ABSTRACT FROM AUTHOR]

Surface properties such as physicochemical characteristics and topographical parameters are important considerations in the design of implant materials, as they determine interactions with living cells and tissues. Micro-/nanostructurization of Ti surfaces can enhance osteointegration, and strontium (Sr) is able to decrease osteoresorption. Sr loaded micro/-nanotubular structures that allow controlled and long-term Sr release are expected to yield favorable osteogenic effects. In this work, we constructed SrTiO 3 /TiO 2 nanoparticle-nanotube heterostructures on a microporous titanium (Ti) surface and characterized their properties. Ti plates were etched with acid to create a micro-rough surface (M) and then anodized to generate a surface layer of TiO 2 nanotubes (MN). Strontium (Sr) was loaded onto MN by hydrothermal treatment in Sr(OH) 2 solution (MN-Sr) for 1 or 3 h to obtain SrTiO 3 /TiO 2 nanotube heterostructures with different Sr contents. The in vitro biocompatibility of MN-Sr was investigated by evaluating protein adsorption, using osteoblast and osteoclast (RAW 264.7 cell) cultures. The micro-/nanostructured porous samples (MN and MN-Sr) promoted protein adsorption owing to their large specific surface area and high reactivity; the amount of protein adsorbed onto MN-Sr was independent of Sr content. Sr in SrTiO 3 /TiO 2 heterostructures exhibited controllable and sustained Sr 2 + ion release in phosphate-buffered saline. Moreover, heterostructures with an appropriate SrTiO 3 content promoted osteoblast adhesion, proliferation and differentiation, and inhibited osteoclast proliferation and differentiation. These results indicate that the micro-/nano heterostructure with an appropriate content of Sr has excellent osteogenic activity and anti-bone resorption ability. [ABSTRACT FROM AUTHOR]

• Simple and efficient method to exfoliate few-layer MoS 2 nanosheets. • Abundant spin edge and vacancy defects favoring ferromagnetic introduction. • Its magnetic properties are competitive among two-dimensional transition metal sulfides. As the most stable layered TMDs, MoS 2 nanosheets has a wide range of applications in transistors, sensors, catalysis, etc. However, thorny preparation problems of layered MoS 2 such as low efficiency, poor repeatability and difficult of mass production limited its development as a functional material. Herein, a novel, oxidation and organic carbon source reduction exfoliation method is proposed to obtain MoS 2 nanosheets. The obtained MoS 2 nanosheets is identified as a bilayer MoS 2 and has excellent ferromagnetism property, which shows 0.155 emu/g for saturation magnetization and 762 K for Curie temperature. The efficient exfoliation method would be a promising candidate for low-cost, large-scale preparation of MoS 2 which may have potential applications in spintronics, nanodevices and photodevices. [ABSTRACT FROM AUTHOR]

Graphical abstract CdS nanoparticles-sensitized high energy facet exposed SnO 2 (TiO 2) elongated octahedral nanoparticles film grown directly on FTO substrates. The as-prepared SnO 2 (TiO 2)/CdS(6) heterostructure showed much higher photocatalytic activities for the degradation of the methyl orange (MO) under visible light irradiation. Highlights • CdS sensitized high energy facet exposed SnO 2 (TiO 2) nanoparticles grown on FTO. • SnO 2 (TiO 2)/CdS photocatalyst showed preferably photocatalytic and PEC properties. • SnO 2 (TiO 2)/CdS film grown directly on FTO made the collection and recycle easily. Abstract The fabrication of well-defined semiconductor based SnO 2 heterostructure is still a great challenge. In this study, SnO 2 (TiO 2) elongated octahedral nanoparticles film was directly produced on FTO substrate by hydrothermal approach and TiCl 4 post-treatment. As a light absorber, CdS nanoparticles were assembled onto the TiCl 4 -treated SnO 2 elongated octahedral nanoparticles (SnO 2 (TiO 2)). We investigated the photocatalytic and photoelectrochemical properties of the prepared SnO 2 (TiO 2)/CdS films. The study found that the prepared SnO 2 (TiO 2)/CdS(6) heterostructure showed much higher photocatalytic activities for the degradation of the methyl orange (MO) under visible light irradiation in comparison with individual SnO 2 (TiO 2) film photocatalyst. The significantly enhanced photocatalytic performance of the SnO 2 (TiO 2)/CdS(6) sample is due to the absorption of visible light and the formation of type-II heterostructure, which plays a role in the effective charge separation. Moreover, these SnO 2 (TiO 2)/CdS films photocatalyst are directly produced on FTO substrates, making the photocatalyst collection and recycling easier than the powders photocatalyst. [ABSTRACT FROM AUTHOR]