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991.
Junho Ahn Hanyong Jin Jaehyeon Park Boeun Lee Mirae Ok Ji Ha Lee Jeehyeon Bae Jong Hwa Jung 《Particle & Particle Systems Characterization》2020,37(9):2000136
Coassembled nanoparticles composed of functionalized mesoporous silica and pillar[5]arene-appended Au nanoparticles obtained through the formation of a host–guest complex are designed and synthesized as a mitochondrial-selective dual-drug delivery system. A pyridinium-based ligand and fluorescein isothiocyanate are immobilized onto mesoporous silica to act as the mitochondria-targeting ligand and fluorescence tracker, respectively, of a material dubbed NP-3. Carboxylated pillar[5]arene-capped Au nanoparticles (CP-AuNPs) are fabricated by the templated reduction of Au3+. Interestingly, coassembled nanoparticles (NP-1) composed of doxorubicin (DOX) loaded NP-3 and CP-AuNPs are then prepared via the formation of a host–guest complex between the pyridinium-based ligand of NP-3 and the pillar[5]arene of CP-AuNPs. To demonstrate the effectiveness of NP-2 and NP-1 as mitochondrial targeting drug delivery systems, DOX and F16 are employed as model drugs. These drugs loaded onto NP-2 and CP-AuNPs, respectively, are selectively delivered to mitochondria, indicating the usefulness of NP-2 and CP-AuNPs as mitochondrial-specific drug-delivery carriers in cancer cells. More interestingly, the use of NP-1 is also associated with the selective accumulation of DOX and F16 in mitochondria. The selective mitochondrial-targeting of NP-1 is possible by NP-2 and F16 exposed to the cytoplasm, allowing the codelivery of the two drugs to the mitochondria. 相似文献
992.
Young Ha Kim Dong Keun Han Seo Young Jeong Kwang-Duk Ahn 《Macromolecular Symposia》1990,33(1):319-326
Surfaces of commercial polyurethanes (PUs) were modified by poly(ethylene oxide) (PEO) grafting and/or heparin immobilization or sulfonation to investigate the effect to antithrombogenicity. The hydrophilicity of the modified PUs surface was significantly increased. All the PEO-grafted PU surfaces displayed very little platelet adhesion and activation. The coupled heparin or sulfonate at the end of PEO exhibited anticoagulant activity to extend APTT. Lowering in vitro platelet adhesion of modified PUs led to a prolongation in the ex vivo occlusion time. In particular, the sulfonated PU-PEO surface showed the most enhanced blood compatibility due to the synergistic effects of PEO and SO3 groups. 相似文献
993.
Balu Alagar Venmathi Maran Mohammad Iqbal Prakash Gangadaran Byeong-Cheol Ahn Pasupuleti Visweswara Rao Muhammad Dawood Shah 《Molecules (Basel, Switzerland)》2022,27(5)
Hepatotoxicity is a major global public health concern. Despite advances in modern medicine, the demerits of chemically prepared drugs outweigh their merits. In addition, the treatment of liver diseases based on modern medical principles has been found to produce several undesired side effects. Therefore, the exploration of medicinal plants has gained worldwide attention for treating various diseases, including liver diseases, owing to their potential efficacy and cost effectiveness. Several plants, including Andrographis paniculata, Bauhinia purpurea, Commelina nudiflora, Dillenia suffruticosa, Elaeis guineensis, Lygodium microphyllum, and Nephrolepis biserrata, have been reported with hepatoprotection. Moreover, these plants have been shown to play a vital role in ameliorating cellular damage because they contain several phytochemicals, including alkaloids, saponins, flavonoids, tannins, terpenoids, steroids, polyphenols, and diterpenoid lactones. The following antioxidant, anti-inflammatory, immunomodulatory, and hepatoprotective compounds have been found in these plants: andrographolide, rosmarinic acid, phenol, eugenol, 9,12-octadecadienoic, n-hexadecanoic acid, dihydroxy dimethoxy flavone, sitosterol, demethoxycurcumin, quercetin, linoleic acid, stigmasterol, kojic acid, indole-2-one, α-terpinol, linalool, kaempferol, catechin, ellagic acid, and oleanolic acid. This paper aimed to provide an in-depth review of in vivo studies on Malaysian medicinal plants possessing hepatoprotective properties, phytochemical ingredients, and antioxidant mechanisms, with an emphasis on the species proven particularly useful for treating hepatic disorders. 相似文献
994.
Yejin Ahn Min Guk Kim Kyungae Jo Ki-Bae Hong Hyung Joo Suh 《Molecules (Basel, Switzerland)》2022,27(8)
Reactive oxygen species (ROS) generated by ultraviolet (UV) exposure cause skin barrier dysfunction, which leads to dry skin. In this study, the skin moisturizing effect of sphingomyelin-containing milk phospholipids in UV-induced hairless mice was evaluated. Hairless mice were irradiated with UVB for eight weeks, and milk phospholipids (50, 100, and 150 mg/kg) were administered daily. Milk phospholipids suppressed UV-induced increase in erythema and skin thickness, decreased transepidermal water loss, and increased skin moisture. Milk phospholipids increased the expression of filaggrin, involucrin, and aquaporin3 (AQP3), which are skin moisture-related factors. Additionally, hyaluronic acid (HA) content in the skin tissue was maintained by regulating the expression of HA synthesis- and degradation-related enzymes. Milk phospholipids alleviated UV-induced decrease in the expression of the antioxidant enzymes superoxidase dismutase1 and 2, catalase, and glutathione peroxidase1. Moreover, ROS levels were reduced by regulating heme oxygenase-1 (HO-1), an ROS regulator, through milk phospholipid-mediated activation of nuclear factor erythroid-2-related factor 2 (Nrf2). Collectively, sphingomyelin-containing milk phospholipids contributed to moisturizing the skin by maintaining HA content and reducing ROS levels in UVB-irradiated hairless mice, thereby, minimizing damage to the skin barrier caused by photoaging. 相似文献
995.
Dr. Olena Vakuliuk Dr. Yong Woong Jun Kateryna Vygranenko Guillaume Clermont Ye Jin Reo Dr. Mireille Blanchard-Desce Prof. Kyo Han Ahn Prof. Dr. Daniel T. Gryko 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(58):13354-13362
New L -shaped fluorophores possessing five conjugated rings have been synthesized through a four-step procedure involving diketopyrrolopyrrole synthesis and its double N-alkylation, followed by trimethylsilyl bromide-mediated rearrangement to thieno[2,3-f]isoindole-5,8-dione and an intramolecular Friedel–Crafts reaction. In comparison with the parent isoindolediones and π-expanded diketopyrrolopyrroles, these new dyes show red-shifted absorption and emission (up to ≈630 nm). Their structural rigidity is responsible for both the observed small Stokes shifts and large fluorescence quantum yields. Tissue imaging studies revealed that these new dyes show advantageous features including minimal autofluorescence interference and pronounced solvent-sensitive emission. Interestingly, there is a fundamental difference between a dye possessing an amino group and its analog bearing an N-alkyl substituent. The former dye under two-photon excitation at 900 nm gives bright images whereas its N-alkylated counterpart does not. A new type of membrane localization has been discovered by an N-alkylated isoindoledione possessing a benzofuryl substituent. In spite of the fact that the fluorescence quantum yield of this dye in a range of solvents is rather low, it does stain cell membranes exclusively. This new mode of cellular staining opens the door towards further development of membrane staining dyes. 相似文献
996.
Effect of Viscosity on the Formation of Porous Polydimethylsiloxane for Wearable Device Applications
Dong-Hyun Baek Hachul Jung Jeong Hun Kim Young Wook Park Dae Wook Kim Ho Seob Kim Seungjoon Ahn Young-Jin Kim 《Molecules (Basel, Switzerland)》2021,26(5)
Medical devices, which enhance the quality of life, have experienced a gradual increase in demand. Various research groups have attempted to incorporate soft materials such as skin into wearable devices. We developed a stretchable substrate with high elasticity by forming a porous structure on polydimethylsiloxane (PDMS). To optimize the porous structure, we propose a manufacturing process that utilizes a high-pressure steam with different viscosities (400, 800, 2100, and 3000 cP) of an uncured PDMS solution. The proposed method simplifies the manufacturing of porous structures and is cost-effective compared to other technologies. Porous structures of various viscosities were formed, and their electrical and mechanical properties evaluated. Porous PDMS (3000 cP) was formed in a sponge-like three-dimensional porous structure, compared to PDMS formed by other viscosities. The elongation of porous PDMS (3000 cP) was increased by up to 30%, and the relative resistance changed to less than 1000 times with the maximum strain test. The relative resistance increased the initial resistance (R0) by approximately 10 times during the 1500-times repeated cycling tests with 30% strain. As a result, patch-type wearable devices based on soft materials can provide an innovative platform that can connect with the human skin for robotics applications and for continuous health monitoring. 相似文献
997.
The band alignment in AlGaN/GaN HEMT devices was investigated using scanning photocurrent microscopy (SPCM) with UV and visible light sources. The polarity of the SPCM on the conduction channel exhibited a switching behavior from p-type to n-type response as the gate bias was increased. The flat-band voltage, which was higher than the DC turn-on voltage, indicates that an ohmic metallic contact was formed for electron transport. We obtained the band offset between the conduction band and the metal Fermi level, which yielded a value of 2.1 eV on average. 相似文献
998.
Mingchong Dai Hyori Lee Yun Jae Yang Dr. Mithun Santra Dr. Chang Wook Song Dr. Yong Woong Jun Ye Jin Reo Prof. Won Jong Kim Prof. Kyo Han Ahn 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(50):11549-11557
Photostable and near-infrared (NIR)-emitting organic fluorophores with large Stokes shifts are in great demand for long-term bioimaging at deeper depths with minimal autofluorescence and self-quenching. Herein, a new class of benzorhodamines and their analogues that are photostable and emit in the NIR region (up to 785 nm) with large Stokes shifts (>120 nm) is reported. The synthesis involves condensation of 7-alkylamino-2-naphthols with 2-[4-(dimethylamino)-2-hydroxybenzoyl]benzoic acid, which leads to bent-shaped benzorhodamines that emit orange fluorescence (≈600 nm); however, introduction of steric hindrance near the condensation site switched the regioselectivity, to provide a linear benzorhodamine system for the first time. The linear benzorhodamine derivatives provide bright fluorescence images in cells and in tissue. A carboxy-benzorhodamine was applied for photothermal therapy of cancer cells and xenograft cancer mice. 相似文献
999.
Henry Opoku Ji Hyeon Lee Benjamin Nketia-Yawson Hyungju Ahn Jae-Joon Lee Jea Woong Jo 《Journal of polymer science. Part A, Polymer chemistry》2022,60(6):985-991
For highly efficient and stable perovskite solar cells (PSCs), hole transport material (HTM) should be designed and synthesized to afford suitable energy levels, high charge transport, efficient passivation ability, and high device stability. Here, we systematically modulated benzo[1,2-b:4,5:b']dithiophene-based polymer by finely controlling the thienyl and pyridyl contents within the conjugated backbone in order to develop a high performance dopant-free HTM for PSCs. We found that the optimized copolymer with 25% of pyridine content exhibits improved energy level, charge transport, and morphology compared with control homopolymers. As a result, remarkably high power conversion efficiencies up to 21.1% were achieved by employing the optimized polymer as a dopant-free HTM in PSCs. 相似文献
1000.
With the ever-growing interest in ubiquitous smart electronics and the Internet of Things, the demand for high-energy-density power sources with aesthetic versatility has increased tremendously. High energy density Li-metal batteries have attracted considerable attention for fulfilling the high energy density requirement of smart electronics. To obtain form factor-free Li-metal batteries with both design diversity and electrochemical reliability, printed solid-state electrolytes are required as a key component because of their viability for the printing/solidification-based fabrication process and electrode-customized chemical/physical properties. This review presents an overview of printed solid-state electrolytes for form factor-free Li-metal batteries with a focus on materials chemistry and fabrication requirements. In addition, their structural/physical/electrochemical properties were discussed in terms of compatibility with Li-metal batteries. 相似文献