Low dimensional heterostructures have potential applications in information, sensing, and energy-related technologies. In order to obtain high-quality low dimensional heterostructures, an essential ...method is tuning chemical composition in a single nanostructure to obtain two or multiple components with well-matched electronic band structures. Here, we present a tutorial review of a unique chemical vapor growth approach with
in situ
switchable solid chemical sources that can build composition-modulated chalcogenide heterostructures in one-dimensional nanowires, quasi one-dimensional nanobelts and two-dimensional atomic layered nanosheets in a controlled manner. This approach has generated a large variety of heterostructures that not only exhibit gradient distribution in chemical composition, but also show sharp interfaces. Diverse integrated photonic and optoelectronic devices are enabled by the composition-modulated heterostructures based on chalcogenides or other material systems.
This article reviews our successful realization of the composition modulated single chalcogenide semiconductor nanostructures.
The organ-on-a-chip (OOAC) is in the list of top 10 emerging technologies and refers to a physiological organ biomimetic system built on a microfluidic chip. Through a combination of cell biology, ...engineering, and biomaterial technology, the microenvironment of the chip simulates that of the organ in terms of tissue interfaces and mechanical stimulation. This reflects the structural and functional characteristics of human tissue and can predict response to an array of stimuli including drug responses and environmental effects. OOAC has broad applications in precision medicine and biological defense strategies. Here, we introduce the concepts of OOAC and review its application to the construction of physiological models, drug development, and toxicology from the perspective of different organs. We further discuss existing challenges and provide future perspectives for its application.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A DNA-based stimulus-responsive drug delivery system for synergetic cancer therapy has been developed. The system is built on a triplex-DNA nanoswitch capable of precisely responding to pH variations ...in the range of ∼5.0–7.0. In extracellular neutral pH space, the DNA nanoswitch keeps a linear conformation, immobilizing multiple therapeutics such as small molecules and antisense compounds simultaneously. Following targeted cancer cell uptake via endocytosis, the nanoswitch inside acidic intracellular compartments goes through a conformational change from linear to triplex, leading to smart release of the therapeutic combination. This stimuli-responsive drug delivery system does not rely on artificial responsive materials, making it biocompatible. Furthermore, it enables simultaneous delivery of multiple therapeutics for enhanced efficacy. Using tumor-bearing mouse models, we show efficient gene silencing and significant inhibition of tumor growth upon intravenous administration of the smart nanoswitch, providing opportunities for combinatorial cancer therapy.
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IJS, KILJ, NUK, PNG, UL, UM
Semiconducting p–n heterojunctions, serving as the basic unit of modern electronic devices, such as photodetectors, solar-energy conversion devices, and light-emitting diodes (LEDs), have been ...extensively investigated in recent years. In this work, high performance self-powered broad-band photodetectors were fabricated based on vertically stacked p–n heterojunctions though combining p-type WSe2 with n-type Bi2Te3 via van der Waals (vdW) epitaxial growth. Devices based on the p–n heterojunction show obvious current rectification behaviors in the dark and superior photovoltaic characteristics under light irradiation. A maximum short circuit current of 18 nA and open circuit voltage of 0.25 V can be achieved with the illumination light of 633 nm (power density: 26.4 mW/cm2), which are among the highest values compared with the ever reported 2D vdW heterojunctions synthesized by chemical vapor deposition (CVD) method. Benefiting from the broad-band absorption of the heterostructures, the detection range can be expanded from the visible to near-infrared (375–1550 nm). Moreover, ascribing to the efficient carriers separation process at the junction interfaces, the devices can be further employed as self-powered photodetectors, where a fast response time (∼210 μs) and high responsivity (20.5 A/W at 633 nm and 27 mA/W at 1550 nm) are obtained under zero bias voltage. The WSe2/Bi2Te3 p–n heterojunction-based self-powered photodetectors with high photoresponsivity, fast photoresponse time, and broad spectral response will find potential applications in high speed and self-sufficient broad-band devices.
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IJS, KILJ, NUK, PNG, UL, UM
Opuntia stricta is a rich source of phenolic compounds. This species generally has strong antioxidant activities in vitro and in vivo. This study aimed to analyze the antioxidant properties of ...phenolic compounds isolated from Opuntia stricta, including its radical scavenging activities and preventive action against Cd-induced oxidative stress in rats. To assess the protection of prickly pear juice extract (PPJE) against Cd-induced hepato-nephrotoxicity and testicular damage, male albino rats received PPJE (250 mg kg−1) and/or Cd (1 mg kg−1) by oral administration and injection, respectively, for five consecutive weeks. The preventive action of PPJE was estimated using biochemical markers of kidney and liver tissues, antioxidant status, and histological examinations. In the present study, the lipid peroxidation, protein carbonyls, antioxidant status, and metallothionein levels were determined in different tissues. The chromatographic analysis indicated that PPJE extract is very rich in phenolic compounds such as verbascoside, catechin hydrate, and oleuropein. Our results showed that PPJE-treated rats had significantly (p < 0.05) decreased Cd levels in liver and kidney tissues. In addition, the administration of PPJE induced a significant (p < 0.05) decrease in lipid peroxidation of 30.5, 54.54, and 40.8 in the liver, kidney, and testicle, respectively, and an increase in antioxidant status in these tissues. Additionally, PPJE showed a strong ability to protect renal, hepatic, and testicular architectures against Cd exposure. This study revealed that PPJE protects against the toxic effects of Cd, possibly through its free radical scavenging and antioxidant activities.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Directional growth of ultralong nanowires (NWs) is significant for practical application of large-scale optoelectronic integration. Here, we demonstrate the controlled growth of in-plane directional ...perovskite CsPbBr3 NWs, induced by graphoepitaxial effect on annealed M-plane sapphire substrates. The wires have a diameter of several hundred nanometers, with lengths up to several millimeters. Microstructure characterization shows that CsPbBr3 NWs are high-quality single crystals, with smooth surfaces and well-defined cross section. The NWs have very strong band-edge photoluminescence (PL) with a long PL lifetime of ∼25 ns and can realize high-quality optical waveguides. Photodetectors constructed on these individual NWs exhibit excellent photoresponse with an ultrahigh responsivity of 4400 A/W and a very fast response speed of 252 μs. This work presents an important step toward scalable growth of high-quality perovskite NWs, which will provide promising opportunities in constructing integrated nanophotonic and optoelectronic systems.
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IJS, KILJ, NUK, PNG, UL, UM
Lung adenocarcinoma (LUAD), a histological subclass of non‐small‐cell lung cancer, is globally the leading cause of cancer‐related deaths. Long noncoding RNAs (lncRNAs) are emerging as cancer ...regulators. Zinc finger protein multitype 2 antisense RNA 1 (ZFPM2‐AS1) is an oncogene in gastric cancer, but its functions have not been investigated in LUAD. We showed that ZFPM2‐AS1 expression is high in LUAD samples based on GEPIA database (http://gepia.cancer-pku.cn/) and validated ZFPM2‐AS1 upregulation in LUAD cell lines. Functionally, ZFPM2‐AS1 facilitated proliferation, invasion, and epithelial‐to‐mesenchymal transition of LUAD cells. Thereafter, we found that ZFPM2 was negatively regulated by ZFPM2‐AS1, and identified the suppressive effect of ZFPM2 regulation by ZFPM2‐AS1 on LUAD progression. Mechanistically, we showed that ZFPM2‐AS1 interacted with up‐frameshift 1 (UPF1) to regulate mRNA decay of ZFPM2. Rescue assays in vitro and in vivo confirmed that ZFPM2‐AS1 regulated LUAD progression and tumor growth through ZFPM2. Taken together, our findings demonstrate a role for the ZFPM2‐AS1–UPF1–ZFPM2 axis in LUAD progression, suggesting ZFPM2‐AS1 as a new potential target for LUAD treatment.
The illustration of lncRNA ZFPM2‐AS1 promoted lung adenocarcinoma progression through cofunctioning with UPF1 to destabilize ZFPM2.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Bimetallic Au-Ag/Co3O4 nanofibers (Au-Ag/Co3O4NFs) were synthesized by an electrospinning method and calcination treatment. Due to the admirable synergic effect of electrocatalytic ability of Au and ...Ag, and the large surface-to-volume ratio of Co3O4 nanofibers caused by their rough surface, the synthesized Au-Ag/Co3O4NFs were applied to a sensing platform for hydrogen peroxide oxidation. Using electrochemical techniques, the novel sensing platform based on Au-Ag/Co3O4NFs shows a wide linear concentration range with high detection sensitivity of 1241.1 μA mM−1 cm−2. This sensitive sensor was also applied to determine H2O2 from human breast cancer cells, indicating its great potential application in physiology and pathology.
Electrospun bimetallic Au-Ag/Co3O4 nanofibers was employed as electrocatalysts to determine H2O2 from human breast cancer cells. Display omitted
•Bimetallic Au-Ag/Co3O4 nanofibers Au-Ag/Co3O4NFs were synthesized by electrospinning.•Au-Ag/Co3O4NFs possess synergic effect of electrocatality and large surface area.•Biosensor exhibits excellent electrocatalytic activity towards hydrogen peroxide.•Au-Ag/Co3O4NFs serve as electrocatalysts for oxidation of H2O2 released from MCF-7.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The delivery of mRNA to manipulate protein expression has attracted widespread attention, since that mRNA overcomes the problem of infection and mutation risks in transgenes and can work as drugs for ...the treatment of diseases. Although there are currently some vehicles that deliver mRNA into cells, they have not yet reached a good balance in terms of expression efficiency and biocompatibility. Here, a DNA nano‐hydrogel system for mRNA delivery is developed. The nano‐hydrogel is all composed of DNA except the target mRNA, so it has superior biocompatibility compared with those chemical vehicles. In parallel, the nano‐hydrogel can be compacted into a nanosphere under the crosslinking by well‐designed “X”‐shaped DNA scaffolds and DNA linkers, facilitating the delivery into cells through endocytosis. In addition, smart intracellular release of the mRNA is achieved by incorporating a pH‐responsive i‐motif structure into the nano‐hydrogel. Thus, taking the efficient delivery and release together, mRNA can be translated into the corresponding protein with a high efficiency, which is comparable to that of the commercial liposome but with a much better biocompatibility. Due to the excellent biocompatibility and efficiency, this nano‐hydrogel system is expected to become a competitive alternative for delivering functional mRNA in vivo.
Delivery of mRNA is attractive for the treatment of diseases, including the COVID‐19. But the delivery vehicles still need to be improved in terms of expression efficiency and biocompatibility. Here, a DNA nano‐hydrogel system for mRNA delivery is developed. It avoids the use of chemical reagents and can achieve pH‐responsive release of mRNA, thus balancing the expression efficiency and biocompatibility.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Novel three-dimensional (3D) hybrid materials, i.e., free-standing 3D graphene-supported MnO2 nanosheets, are prepared by a simple and controllable solution-phase assembly process. Characterization ...results show that MnO2 nanosheets are uniformly anchored on a 3D graphene framework with strong adhesion and the integral hybrids show desirable mechanical strength. Such unique structure of 3D graphene/MnO2 hybrids thus provides the right characteristics of binder-free electrode materials and could enable the design of different kinds of high-performance energy storage devices. Especially, an advanced asymmetric supercapacitor is built by using a 3D graphene/MnO2 hybrid and a 3D graphene as two electrodes, and it is able to work reversibly in a full operation voltage region of 0–3.5 V in an ionic liquid electrolyte and thus exhibits a high energy density of 68.4 Wh/kg. As the cathode materials for Li–O2 and Li–MnO2 batteries, the 3D graphene/MnO2 hybrids exhibit outstanding performances, including good catalytic capability, high reversible capacity and desirable cycling stability. The results presented here may pave a way for new promising applications of such 3D graphene/MnO2 hybrids in advanced electrochemical energy storage devices.
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IJS, KILJ, NUK, PNG, UL, UM
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