• Journal of the Korean Ceramic Society
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• v.55 no.5
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• pp.510-514
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• 2018

Colloidal semiconductor quantum dots (QDs), because of the novel optical and electrical properties that stem from their three-dimensional confinement, have attracted great interest for their potential applications in such fields as bio-imaging, display, and opto-electronics. However, many semiconductors that can be exploited for QD applications contain toxic elements. Herein, we synthesized non-toxic ZnTe/ZnSe (core/shell) type-II QDs by pyrolysis method. Because of the unique type-II character of these QDs, their emission can range over an extended wavelength regime, showing photoluminescence (PL) from 450 nm to 580 nm. By optimizing the ZnSe shell growth condition, resulting ZnTe/ZnSe type-II QDs shows PL quantum yield up to ~ 25% with 35 nm PL bandwidth. Using a simple two step cation exchange reaction, we also fabricated ZnTe/ZnSe type-II QDs with absorption extended over the whole visible region. The visible-light sensitized heavy metal free ZnTe/ZnSe type-II QDs can be relevant for opto-electronic applications such as displays, light emitting diodes, and bio-imaging probes.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.124.2-124.2
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• 2007

• Journal of Animal Reproduction and Biotechnology
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• v.37 no.4
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• pp.239-245
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• 2022

Protein and peptide candidates are screened to apply therapeutic application as a drug. Ensuring that these candidates are delivered and maximized effectiveness is still challenging and a variety of studies are ongoing. As drug delivery system vehicles, cell-penetrating peptide (CPP) can deliver various kinds of cargo into the cell cytosol. In a previous study, we developed Ara27 CPP, which are a zinc knuckle family protein of Arabidopsis, and confirmed internalization in human dermal fibroblasts and human dental pulp stem cells at low concentration with short time treatment condition without any toxicity. Ara27, an amphipathic CPP, could be modified and utilized in the biomedical field excluding the risk of toxicity. Therefore, we would like to confirm the non-toxic induced penetrating ability of Ara27 in various cell lines. The purpose of this study was to screen the cell internalization ability of Ara27 in various cell lines and to confirm Ara27 as a promising core CPP structure. First, Ara27 was screened to confirm non-toxicity concentration. Then, fluorescence-labeled Ara27 was treated on human normal cell lines, cancer cell lines and animal cell lines to identify the cellular internalization of Ara27. Ara27 was well intracellular localized in all cell lines and the intensity of fluorescence was remarkably increased in time pass manner. These results indicate that Ara27 has the potential as a core structure for applications in various drug delivery systems.

• Journal of Powder Materials
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• v.22 no.6
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• pp.385-390
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• 2015

We report a synthesis of non-toxic InP nanocrystals using non-pyrolytic precursors instead of pyrolytic and unstable tris(trimethylsilyl)phosphine, a popular precursor for synthesis of InP nanocrystals. In this study, InP nanocrystals are successfully synthesized using hexaethyl phosphorous triamide (HPT) and the synthesized InP nanocrystals showed a broad and weak photoluminescence (PL) spectrum. As synthesized InP nanocrystals are subjected to further surface modification process to enhance their stability and photoluminescence. Surface modification of InP nanocrystals is done at $230^{\circ}C$ using 1-dodecanethiol, zinc acetate and fatty acid as sources of ZnS shell. After surface modification, the synthesized InP/ZnS nanocrystals show intense PL spectra centered at the emission wavelength 612 nm through 633 nm. The synthesized InP/ZnS core/shell structure is confirmed with X-ray diffraction (XRD) and Inductively Coupled Plasma - Atomic Emission Spectrometer (ICP-AES). After surface modification, InP/ZnS nanocrystals having narrow particle size distribution are observed by Field Emission Transmission Electron Microscope (FE-TEM). In contrast to uncapped InP nanocrystals, InP/ZnS nanocrystals treated with a newly developed surface modified procedure show highly enhanced PL spectra with quantum yield of 47%.

• Applied Chemistry for Engineering
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• v.20 no.1
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• pp.52-61
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• 2009

In this study, TAPEH (t-amyl peroxy 2-ethyl hexanoate) was selected for the reaction initiator which is a core factor for developing acrylic polyol binder. Tone M100 (caprolactone acrylate), 4HBA (4-hydroxy butyl acrylate), and 2HEMA (2-hydroxy ethyl methacrylate) were used for hydroxy-monomers. To check the applicability of raw materials mentioned above into the binders of 2 components acrylic polyurethane paint and reduce the VOC, the reactivity and film performance by different kinds of aliphatic polyisocyanate hardeners which are already generalized were reviewed. As the Tin-based catalyst has been regulated, the comparison test of reactivity and performance between the conventional catalyst and non-toxic metal catalyst recommended as the alternative was conducted as well. As a result, we were able to obtain the basic data which are necessary for applying 2 components high solid polyurethane paint and also reached a conclusion that it can be applied for developing new paints in terms of high performance, workability and environmental care.

• The Journal of Internal Korean Medicine
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• v.39 no.5
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• pp.973-983
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• 2018

Objectives: We report a case of traditional Korean medicine (TKM) treatment for skin side effects after taking afatinib (Giotrif$^{(R)}$). Methods: A 62-year-old female who was diagnosed with non-small cell lung cancer stage 4 (T4N2M1b) and was on treatment with afatinib (29.56 mg/day for 4 months) complained of skin toxicity as a side effect. For 16 admission days, the patient was treated with acupuncture, moxibustion, and herbal medicine (oral decoction and external ointment). Results: Improvement of skin toxicity was measured by a numeric rating scale. In addition, Quality of life (QOL) was measured using EORTC Quality of Life Questionnaire, Core 30 (EORTC QLQ-C30) and EORTC Quality of Life Questionnaire, 13-item lung cancer-specific module (EORTC QLQ-LC13) Developed by the European Organization for Research and Treatment of Cancer (EORTC). Tumor size and carcinoembryonic antigen (CEA) were also examined during follow up. Conclusions: After a combined TKM treatment, skin toxicity symptoms and quality of life scales were significantly improved with no side effects. The tumor size was not changed on computed tomography during follow-up period. CEA levels were decreased.