• 전자공학회논문지 IE
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• v.43 no.1
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• pp.1-4
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• 2006

The characteristics of polymeric thin-film transistors(TFTs) can be controlled by chemically modifying the surface of the gate dielectric prior to the organic semiconductor. The chemical treatment consists of derivative the tantalum pentoxide($Ta_2O_5$) surface with organic materials to form self-assembled monolayer(SAM). The deposition of an octadecyl-trichlorosilane(OTS), hexamethy-ldisilazone(HMDS), aminopropyltreithoxysilane(ATS) SAM leads to a mobility of $0.01\sim0.06cm2/V{\cdot}s$ in a poly-3-hexylthiophene(P3HT) conjugated polymer. The mobility enhancement mechanism is likely to involve molecular interactions between the polymer and SAM. These result can be used for polymer TFT's dielectric material.

• Journal of Dairy Science and Biotechnology
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• v.33 no.4
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• pp.271-275
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• 2015

Colloidal semiconductor CdSe-ZnS core-shell nanocrystal quantum dot (Qdot) are luminescent inorganic fluorophores that show potential to overcome some of the functional limitations encountered with organic dyes in fluorescence labeling applications. Salmonella Enteritidis has emerged as a major cause of human salmonellosis worldwide since the 1980s. A rapid, specific, and sensitive method for the detection of Salmonella Enteritidis was developed using Qdot as a fluorescence marker coupled with immunomagnetic separation. Magnetic beads coated with anti-Salmonella Enteritidis antibodies were employed to selectively capture the target bacteria, and biotin-conjugated anti-Salmonella antibodies were added to form sandwich immune complexes. After magnetic separation, the immune complexes were labeled with Qdot via biotin-streptavidin conjugation, and fluorescence measurement was carried out using a fluorescence measurement system. The detection limit of the Qdot method was a Salmonella Enteritidis concentration of $10^3$ colony-forming units (CFU)/mL, whereas the conventional fluorescein isothiocyanate-based method required over $10^5CFU/mL$. The total detection time was within 2 h. In addition to the potential for general nanotechnology development, these results suggest a new rapid detection method of various pathogenic bacteria from a complex food matrix.

• Applied Chemistry for Engineering
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• v.30 no.4
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• pp.429-434
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• 2019

A lateral flow immunoassay platform utilizing antibody functionalized water soluble CdSe/ZnS semiconductor quantum dots (QDs) was developed for the analysis of human serum amyloid A-1 (hSAA1) in a buffer solution. hSAA1 was chosen as a target protein because it is regarded as a potential biomarker associated with early diagnosis and prognosis in patients of lung cancer. The immunoassay strip on a nitrocellulose membrane was fabricated by spraying two lines composed of a test line with a monoclonal antibody against hSAA1 (10G1) (anti hSAA1) and a control line of anti-chicken IgY. While the CdSe/ZnS QDs synthesized in an organic phase were transferred to a water phase by ligand exchange using carboxylic acid modified alkane thiol. The QDs was then conjugated to monoclonal antibody against hSAA1 (14F8) [anti hSAA1 (14F8)] and used as a fluorescent detection probe. The sequential lateral flow of hSAA1 in different concentration and QDs-anti hSAA1 (14F8) complex allowed to form the surface sandwich complex of anti hSAA1 (10G1)/hSAA1/QD-anti hSAA1 (14F8), which was then analyzed using fluorescence microscope. A 100 nM concentration of hSAA1 protein can be detected by naked eyes under an optimized lateral flow buffer condition with a sensing time of 5 mins.

• Journal of Adhesion and Interface
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• v.24 no.2
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• pp.64-68
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• 2023

Organic field-effect transistors (OFETs) are attracting attention in the field of next-generation electronic devices, and they can be fabricated on a flexible substrate using an organic semiconductor as a channel layer. In particular, DPP-based semiconducting conjugated polymers are actively used because they have higher charge carrier mobility than other organic semiconductors, but they are still lower than inorganic semiconductors, so various studies are being conducted to improve the charge carrier mobility. In this study, the charge carrier mobility is improved by controlling the surface energy of the substrate by forming self-assembled monolayers (SAMs). As the surface energy of the substrate is controlled by the SAMs, the crystallinity increases, thereby improving the charge carrier mobility by 14 times from 3.57×10^-3 cm²V^-1s^-1 to 5.12×10^-2 cm²V^-1s^-1