PET/CT에서 Pitch와 Rotation Time의 변화를 이용한 능동적인 프로토콜 사용에 대한 연구

장의순,곽인석,박선명,최춘기,이혁,김수영,최성욱,Jang, Eui Sun,Kwak, In Suk,Park, Sun Myung,Choi, Choon Ki,Lee, Hyuk,Kim, Soo Young,Choi, Sung Wook 대한핵의학기술학회 2013 핵의학 기술 Vol.17 No.2

PET/CT검사에서 CT촬영조건의 변화는 영상의 화질 및 환자가 받는 피폭선량에 영향을 미친다. 본 연구는 CT 매개 변수 중 Pitch와 X-선관 회전시간 변화에 따른 선량대비 CT 영상의 질과 이로 인해 PET상에서 SUV에 미치는 영향을 비교 평가하고자 하였다. Discovery STe PET/CT 장비를 이용하여 영상을 획득하였다. QA Phantom과 AAPM Phantom을 이용한 CT 영상 획득 시 Pitch는 0.562, 0.938, 1.375, 1.75:1로 4단계, X-선관 회전시간은 0.5에서 1.0까지 0.1초씩 증가시켜 6단계로 나누어 총 24개 조합을 적용한 영상을 각각 획득하였다. PET 영상은 $^{18}F-FDG$ 5.3 kBq/mL가 채워진 1994 NEMA PET Phantom을 이용하여 프레임당 2분 30초의 방출영상을 획득하였다. 각 조합의 CT 영상에 관심영역을 설정하고 CT number의 표준편차를 측정하였다. 동일한 영상에서 DLP변화에 따른 영상잡음의 예측값을 계산하여 예측값 대비 실측값의 비율을 구해 선량대비 영상잡음 효과를 비교하는 척도로 사용하였다. AAPM Phantom 영상에서 1.0 mm까지 식별이 가능한 지 확인하였다. NEMA PET Phantom의 방출영상에 관심영 역을 설정하고 SUV를 비교 평가하였다. Pitch가 0.562, 0.938, 1.375, 1.75:1로 변화할 때 영상잡음 효과는 QA Phantom에서 1.00, 1.03, 1.01, 0.96, AAPM Phantom에서 1.00, 1.04, 1.02, 0.97로 측정되었다. 회전시간의 증가에 따른 경우 QA Phantom에서 0.99, 1.02, 1.00, 1.00, 0.99, 0.99이었고, AAPM Phantom에서 1.01, 1.01, 0.99, 1.01, 1.01, 1.01로 SPSS Ver. 18을 이용하여 상관관계를 분석한 결과 피어슨 상관계수는 -0.059로 나타났다. 공간분해능에 대한 평가는 24개의 조합 모두에서 1.0 mm까지 육안으로 구별이 가능하였다. SUV의 경우 평균 SUV는 모든 조합에서 1.1로 모두 동일한 값을 나타내었다. Pitch 변화에 따른 CT 영상 평가에서 1.75:1을 적용 시 선량대비 가장 적은 영상잡음 효과를 보이며 공간분해능과 SUV에는 영향을 미치지 않는다. 그러나 회전시간 변화가 영상에 미치는 영향에는 유의한 차이가 없음을 알 수 있다. 결과에서와 같이 각 장비에 따른 선량대비 영상잡음이 적은 Pitch를 사용하고 환자의 체격에 따른 적절한 X-선관 회전시간을 이용한다면 환자의 피폭선량을 줄이면서 최적의 화질을 얻을 수 있는 프로토콜을 구성하는데 도움이 될 것이라 사료된다. Purpose: The Change of CT exposure condition have a effect on image quality and patient exposure dose. In this study, we evaluated effect CT image quality and SUV when CT parameters (Pitch, Rotation time) were changed. Materials and Methods: Discovery Ste (GE, USA) was used as a PET/CT scanner. Using GE QA Phantom and AAPM CT Performance Phantom for evaluate Noise of CT image. Images are acquired by using 24 combinations that four stages pitch (0.562, 0.938, 1.375, 1.75:1) and six stages X-ray tube rotation time (0.5s-1.0s). PET images are acquired using 1994 NEMA PET Phantom ($^{18}F-FDG$ 5.3 kBq/mL, 2.5 min/frame). For noise test, noise are evaluated by standard deviation of each image's CT numbers. And then we used expectation noise according to change of DLP (Dose Length Product) to experimental noise ratio for index of effectiveness. For spatial resolution test, we confirmed that it is possible to identify to 1.0 mm size of the holes at the AAPM CT Performance Phantom. Finally we evaluated each 24 image's SUV. Results: Noise efficiency were 1.00, 1.03, 1.01, 0.96 and 1.00, 1.04, 1.02, 0.97 when pitch changes at the QA Phantom and AAPM Phantom. In case of X-ray tube rotation time changes, 0.99, 1.02, 1.00, 1.00, 0.99, 0.99 and 1.01, 1.01, 0.99, 1.01, 1.01, 1.01 at the QA Phantom and AAPM Phantom. We could identify 1.0 mm size of the holes all 24 images. Also, there were no significant change of SUV and all image's average SUV were 1.1. Conclusion: 1.75:1 pitch is the most effective value at the CT image evaluation according to pitch change and It doesn't affect to the spatial resolution and SUV. However, the change of rotation time doesn't affect anything. So, we recommend to use the effective pitch like 1.75:1 and adequate X-ray tube rotation time according to patient size.

탄소전극 두께에 따른 축전식 탈염 장치의 탈염성능 연구

장의순,최재환 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.1

Lipofectamine-2000 Assisted Magnetofection to Fibroblast Cells Using Polyethyleneimine-Fe3O4@SiO2 Nanoparticles

장의순,Kyeong Soon Park 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.8

We successfully synthesized Fe3O4@SiO2 nanoparticles with ultrathin silica layer of 1.0 ± 0.5 nm that polyethyleneimine (PEI) with low molecular weight of 2.0-4.0 kDa was covalently conjugated with the resulting Fe3O4@SiO2 nanoparticles by silane coupling reaction. The PEI-Fe3O4@SiO2 nanoparticles were further used as gene delivery vector for a human fibroblast cell (IMR-90) line. Gene transfection efficiency of the PEI-Fe3O4@SiO2 complexes did not increase remarkably after magnetofection; however, the addition of Lipofectamine 2000 significantly increased the transfection efficiency of the PEI-Fe3O4@SiO2 complexes. We believe that the present approach could be utilized for magnetofection as alternative to Fe3O4 nanoparticles conjugated with the PEI of high molecular weight thanks to its relatively low cytotoxicity and high transfection efficiency.

판상형 산화아연의 합성 및 응용에 관한 연구 동향

장의순 한국세라믹학회 2017 세라미스트 Vol.20 No.4

As one of the most versatile semiconductors, zinc oxide (ZnO) with one-dimensional (1-D) nanostructures has been significantly developed for the application of ultraviolet (UV) lasers, photochemical sensors, photocatalysts, and so on. Such 1-D nanowires could be easily achieved due to the anisotropic growth rate along the [0001] direction. However, such typical growth habit leads to decrease the surface area of the (0001) plane, which plays a central role in not only UV lasing action but also photocatalytic reaction. This fact lead us to develop ZnO crystal with enhanced polar surface area through crystal growth control. The purpose of this review is to provide readers a simple route to plate-type ZnO crystal with highly enhanced polar surfaces and their applications for UV-laser, photocatalyst, and antibacterial agents. In addition, we will highlight the recent study on pilot-scale synthesis of plate-type ZnO crystal for industrial applications.

증인

장의순 문예운동사 2016 수필시대 Vol.11 No.1·2

바이오 물질 분석을 위한 금속 나노입자를 이용한 SERS 분석 연구동향

장의순(Eue-Soon Jang) 한국세라믹학회 2019 세라미스트 Vol.22 No.3

Surface enhanced Raman scattering (SERS) was first discovered in 1974 by an unexpected Raman signal increase from Pyridine adsorbed on rough Ag electrode surfaces by the M. Fleishmann group. 1) M. Moskovits group suggested that this phenomenon could be caused by surface plasmon resonance (SPR), which is a collective oscillation of free electrons at the surface of metal nanostructures by an external light source. 2-14) After about 40 years, the SERS study has attracted great attention as a biomolecule analysis technology, and more than 2500 new papers and 500 review papers related to SERS topic have been published each year in recently. 15) The advantages of biomaterials analysis using SERS are as follows; ① Molecular level analysis is possible based on unique fingerprint information of biomolecule, 16-20) ② There is no photo-bleaching effect of the Raman reporters, allowing long-term monitoring of biomaterials compared to fluorescence microscopy, ③ SERS peak bandwidth is approximately 10 to 100 times narrower than fluorescence emission from organic phosphor or quantum dot, resulting in higher analysis accuracy, 21), 22) ④ Single excitation wavelength allows analysis of various biomaterials, ⑤ By utilizing near-infrared (NIR) SERSactivated nanostructures and NIR excitation lasers, auto-fluorescence noise in the visible wavelength range can be avoided from in vivo experiment and light damage in living cells can be minimized compared to visible lasers, ⑥ The weak Raman signal of the water molecule makes it easy to analyze biomaterials in aqueous solutions. For this reason, SERS is attracting attention as a next-generation non-invasive medical diagnostic device as well as substance analysis. In this review, the principles of SERS and various biomaterial analysis principles using SERS analysis will be introduced through recent research papers.

SERS Signal Enhancement of Methylene Blue-embedded Agglomerated Gold Nanorod@SiO2 Core@Shell Composites

심규동,장의순 대한화학회 2018 Bulletin of the Korean Chemical Society Vol.39 No.8

In medical science, Raman spectroscopy has received considerable attention as the next noninvasive diagnostic imaging technique. However, its clinical applications are limited by the weak signal intensities of Raman active molecules. Previously, we showed that a methylene-blue-loaded gold nanorod@silica (MB-GNR@SiO2) core@shell nanostructure is promising for the development of a cancer theranostic agent due to its excellent surface-enhanced Raman scattering (SERS) performance and synergistic cancer-destroying efficacy. In this study, we successfully synthesized MB-embedded agglomerated gold nanorod@SiO2 (MB-A.GNR@SiO2) composites, in which the many interparticle junctions created by the agglomerated GNRs were able to enhance the SERS signal of the loaded MB by a factor of five compared to MB-GNR@SiO2. This high SERS performance of the present MB-A.GNR@SiO2 could provide us with an approach to explore a rapid and ultra-sensitive SERS detection method for various biological molecules.

Biocompatible Materials Coated Superparamagnetic lron Oxide Nanopar-Ticles for NIRF/MRI Multi Modal Cancer Imaging

차의준,장의순,선인철,이인준,김영일,김광명,권익찬,안철희 한국고분자학회 2010 한국고분자학회 학술대회 연구논문 초록집 Vol.2010 No.10

Reduced cytotoxicity of CTAB-templated silica layer on gold nanorod using fluorescence dyes and its application in cancer theranostics

한효원,조아라,장의순 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.96 No.-

Cytotoxicity of cetyltrimethylammonium bromide (CTAB)-templated silica-coated gold nanorod(CGNR@SiO2) was confirmed to be severe even after the washing process because of the residualCTAB surfactant. Calcination to eliminate the CTAB template induced dissolution of the gold nanorod(GNR) core and caused a blue-shift in the longitudinal surface plasmon resonance (LSPR) mode of theGNR from the near-infrared to visible wavelength. In contrast, the CTAB template was effectively removedfrom CGNR@SiO2 without interference of the plasmonic property of the core GNR by aminefunctionalizedfluorescence dyes such as methylene blue (MB) and rhodamine B (RB). The RB was moreefficient in substituting the residual CTAB through electrostatic interactions than the MB. Moreover, theresulting products exhibited excellent surface-enhanced Raman scattering performance to detect a fewcancer cells. The MB and RB molecules as visible light photosensitizer (PS) were activated by near-infrared (NIR) excitation light through transfer of the NIR-driven plasmonic hot electrons from the coreGNR to the PS molecules. It is noteworthy that the RB-loaded CGNR@SiO2 exhibited excellent cancer cellkilling efficiency via generation of abundant reactive oxygen species (ROS) under NIR laser irradiation,although the concentration of the intracellular GNR was too low to induce the photothermal effect.

Development of MRI/NIRF ‘activatable’ multi-modal imaging probe using Fe₃O₄@SiO₂ core-shell nanoparticles

차의준,김지현,장의순,선인철,이인준,김영일,김광명,권익찬,안철희 한국고분자학회 2011 한국고분자학회 학술대회 연구논문 초록집 Vol.2011 No.1