• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2003년도 제27회 추계학술대회
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• pp.3-11
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• 2003

• 대한핵의학회지
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• 제38권2호
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• pp.121-130
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• 2004

Molecular imaging visualizes cellular processes at a molecular or genetic level in living subjects, and diverse molecular probes are used for this purpose. Radiolabeling methods as well as radioisotopes are very important in preparation of molecular probes, because they can affect the biodistribution in tissues and the excretion route. In this review, the molecular probes are divided into small organic molecules and macromolecules such as peptides and proteins, and their commonly used radiolabeling methods are described.

• 대한의용생체공학회:의공학회지
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• 제16권3호
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• pp.309-316
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• 1995

핵자기공명(Nuclear Magnetic Resonance)에서 신호 획득 시에 가장 중요한 부분중의 하나인 rf-탐침(radio-frequency-probe)은 실험대상이 되는 시료의 기하학적 모양과 획득하고자 하는 정보 등에 따라서 적절히 설계 및 제작되어야 최적의 신호를 얻을 수 있다. 일반적으로, rf-탐침은 시료를 둘러싸는 형태와 시료 표면에 위치하는 형태 등 두 가지로 제작된다. 그러나, 시료나 인체 부위가 관모양을 하고 있으며 관 모양 주위로부터의 신호를 관측하는 경우, 앞에서 기술한 두가지 형태의 탐침을 이용해서는 신호대 잡음비의 저하로 인해 만족할 만한 신호 획득이 어려워진다. 이때, 탐침을 관 모양의 시료 내부에 위치시키고, 관찰하고자 하는 부위에 최대로 가까이하며 탐침의 품격인자를 높이는 것이 최적의 신호획득에 중요한 조건이 되게 된다. 본 논문에서는 탐침을 시료 내부에 넣고 탐침 외부로부터 신호를 얻는 뒤집음-탐침을 역-솔레노이드 saddle 및 이중표면코일 등의 세가지 형태로 제작하고 최적신호의 획득에 대한 시도를 해보았고, 컴퓨터를 이용한 계산을 통하여 기하학적인 모양의 차이에 따른 rf-자기장 발생 상태를 알아보았다. 아울러, 시험시료로부터 발생되는 영상신호를 얻고 영상 영역 내에서 신호대잡음비를 측정하여 탐침들의 성능을 비교 분석했다. 본 연구에서 제작된 뒤집음-탐침의 경우, 어떠한 상품화된 탐침과 비교할 때, 뛰어난 신호대잡음비와 탐침 주위에서 매우 높은 균일성이 유지되었다. 또한, 제작된 형태의 뒤집음-탐침을 이용한 인체 진단에의 응용성은 매우 높을 것으로 예상된다.

• 대한방사성의약품학회지
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• 제3권1호
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• pp.25-31
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• 2017

Liposomes are defined as spherical, self-closed structures formed by lipid bilayers containing aqueous phase. Most liposomes are composed of various amphipathic lipids such as phospholipids and cholesterol. We used amphipathic lipids (DPPC, DPPG) as liposome components and prepared around 100 nm liposomes by standard extrusion method. Nuclear/MR dual imaging agents based on liposome platform were prepared by adding radioactive $^{131}I$-HIB (hexadecyl-4-tributylstannylbenzoate) and Gd-DTPA into liposome bilayer and inside liposome, respectively. Gamma camera and MR imaging both showed signal increases in liver.

• 대한방사성의약품학회지
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• 제4권1호
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• pp.26-31
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• 2018

Macrophages play a key role in atherosclerotic plaque formation, but their participation has been discerned largely via ex vivo analyses of atherosclerotic lesions. Therefore, we aimed to identify atherosclerosis on noninvasive in vivo imaging using reporter gene system. This study demonstrated that recruitment of macrophages could be detected in atherosclerotic plaques of Apolipoprotein E knockout (ApoE-/-) mice with a sodium iodide symporter (NIS) gene imaging system using $^{99m}Tc-SPECT$. This novel approach to tracking macrophages to atherosclerotic plaques in vivo could have applications in studies of arteriosclerotic vascular disease.

• 대한방사성의약품학회지
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• 제7권1호
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• pp.56-65
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• 2021

TSPO, an 18-kDa translocator protein, is a peripheral-type benzodiazepine receptor that has been associated to a variety of biological activities such as apoptosis, steroidogenesis, and cell proliferation. Because TSPO overexpression has been found in various forms of cancer, it has recently become one of the most appealing biological targets for cancer therapies and detection. In order to create new optical imaging agents for improved diagnostics, we synthesized a novel dimeric fluorescent TSPO ligand based on PRB28 structure and SCy5.5. Following the preparation of the novel TSPO ligand, in vivo and ex vivo imaging tests were performed to examine the tumor uptake characteristics of the fluorescent TSPO ligand in a glioma animal model, and it was found that novel TSPO ligand was accumulated in glioma. These results suggested that novel dimeric fluorescent TSPO ligand will be applied to detect glioma.

• 대한방사성의약품학회지
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• 제7권2호
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• pp.127-131
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• 2021

Neuroendocrine tumor is one of popular diseases, and somatostatin receptor antagonists have been considered as promising agents for neuroendocrine tumors. Imaging of somatostatin receptor is useful approach on the diagnosis and therapy of neuroendocrine tumors. Thus, several radiolabeled somatostatin derivatives have been developed by scientists, and used for patients with neuroendocrine tumors. In particular, some radiopharmaceuticals for neuroendocrine tumors were approved by FDA. In this highlight review, the development of important radiolabeled somatostatin derivatives is described.

• 대한방사성의약품학회지
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• 제1권1호
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• pp.46-52
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• 2015

Herein we present the synthesis of $^{68}Ga$-labeled gold nanoparticles for in vivo PET imaging. A novel chelator DTPA-Cys was easily prepared from diethylenetriaminepentaacetic dianhydride in high yield. The ${\alpha}_v{\beta}_3$ integrin receptor targeted gold nanoparticle probe was synthesized by using DTPA-Cys, polyethylene glycol and cRGD peptide. $^{68}Ga$ labeling of cRGD conjugated gold nanoparticle was carried out at $40^{\circ}C$ for 30 min. Observed radiochemical yield was more than 75% as determined by radio-TLC and the probe was purified by centrifugation. In vitro stability test showed that 90% of $^{68}Ga$-labeled gold nanoparticle probe was stable in FBS for 1 h. Those results demonstrated that $^{68}Ga$-labeled gold nanoparticle could be used as a potentially useful probe for specific tumor imaging.

• 대한방사성의약품학회지
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• 제2권1호
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• pp.37-42
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• 2016

The translocator protein (TSPO) has attracted scientist's attention for Positron Emission Tomography (PET) imaging due to correlation with brain cancer, stroke, and neurodegeneration. Recently, GE-180, a novel tricyclic derivative has been developed as a new high affinity agent for the TSPO and evaluated to confirm a possibility for the TSPO ligand. In this highlight review, several studies for the novel TSPO radiotracer are described.

• 대한방사성의약품학회지
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• 제5권1호
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• pp.61-68
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• 2019

Purine type compounds has been recently reported to cause the death for lung cancer cell, related to microtubules-targeting agents (MTAs). Therefore it can be used to develop as theranostic radiopharmceuticals in nuclear medicine or gadolinium-based MRI imaging agents by chelate chemistry. In the study, we tried to chemically bind a DOTA chelate on the end of purine compound and obtained a specific conjugate of DOTA-purine for metal coordination. In particular, radiometal like Cu-64, for the development of MRI imaging agents, can be utilized to choice good candidates before the synthesis of gadolinium complexes. By the screening of radioisotope technique, Gd-DOTA-purine type complex was successfully prepared and showed MRI imaging for lung cancer cell into the mouse model.