Publications by authors named "Yun-Ok Oh"

We have prepared a core-shell magnetic silica-coated hydroxyapatite, Fe₃O₄@SiO₂@HAp composite materials for pH-responsive drug delivery applications. Captopril (Cap) and ibuprofen (Ibu) were chosen as model hydrophilic and hydrophobic drugs, respectively. The drugs were encapsulated into the Fe₃O₄@SiO₂@HAp composite via electrostatic interactions with existing amine and carboxylic acid groups during calcium phosphate shell formation.

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The development of novel photothermal ablation agents as cancer nanotheranostics has received a great deal of attention in recent decades. Biocompatible fucoidan (Fu) is used as the coating material for gold nanorods (AuNRs) and subsequently conjugated with monoclonal antibodies against epidermal growth factor receptor (anti-EGFR) as novel photothermal ablation agents for cancer nanotheranostics because of their excellent biocompatibility, biodegradability, nontoxicity, water solubility, photostability, ease of surface modification, strongly enhanced absorption in near-infrared (NIR) regions, target specificity, minimal invasiveness, fast recovery, and prevention of damage to normal tissues. Anti-EGFR Fu-AuNRs have an average particle size of 96.

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Cancer nanotechnology is emerging as one of the promising strategies combining photothermal therapy (PTT) and photoacoustic imaging (PAI) for the treatment of breast cancer and it has received considerable attention in the recent years because it is minimally invasive, prevents damage to non-targeted regions, permits fast recovery, and involves breast cancer imaging. The present study demonstrates multifunctional biocompatible chitosan-polypyrrole nanocomposites (CS-PPy NCs) as novel agents for photoacoustic imaging-guided photothermal ablation of cancer because of their biocompatibility, conductivity, stability, and strong near-infrared (NIR) absorbance. The CS-PPy NCs are spherical in shape and range 26-94 nm in size with a mean value of 50.

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Polymeric nanoparticles are emerging as promising candidates for photo-based therapy and imaging due to their versatile chemical properties and easy fabrication and functionalization. In the present study we synthesized polypyrrole nanoparticles by stabilization with astaxanthin conjugated bovine serum albumin polymer (PPy@BSA-Astx). The synthesized nanoparticles were biocompatible with MBA-MD-231 and HEK-293 cells.

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Polymer nanoparticles are emerging as a useful tool for a wide variety of biomedical and therapeutic applications. The present study demonstrates the multifunctional doxorubicin-loaded fucoidan capped gold nanoparticles (DOX-Fu AuNPs) for drug delivery and photoacoustic imaging (PAI). Biocompatible AuNPs were synthesized using a naturally occurring fucoidan (Fu) as a capping and reducing agent.

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Astaxanthin, a kind of photosynthetic pigment, was employed for gold nanoparticle formation. Nanoparticles were characterized using Ulteraviolet-Visible (UV-Vis) spectroscopy, transmission electron microscopy, and X-ray diffraction, and the possible presence of astaxanthin functional groups were analyzed by Fourier transform infrared spectroscopy (FTIR). The cytotoxic effect of synthesized nanoparticles was evaluated against MDA-MB-231 (human breast cancer cells) using a tetrazolium-based assay, and synthesized nanoparticles exhibited dose-dependent toxicity.

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Intravascular ultrasound (IVUS) imaging is extremely important for detection and characterization of high-risk atherosclerotic plaques as well as gastrointestinal diseases. Recently, intravascular photoacoustic (IVPA) imaging has been used to differentiate the composition of biological tissues with high optical contrast and ultrasonic resolution. The combination of these imaging techniques could provide morphological information and molecular screening to characterize abnormal tissues, which would help physicians to ensure vital therapeutic value and prognostic significance for patients before commencing therapy.

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