Carbon micropatterns (CMs) were fabricated from a negative-type SU-8 photoresist by proton ion beam lithography and pyrolysis. Well-defined negative-type SU-8 micropatterns were formed by proton ion beam lithography at the optimized fluence of 1×1015 ions cm–2 and then pyrolyzed to form CMs. The crosslinked network structures formed by proton irradiation were converted to pseudo-graphitic structures by pyrolysis. The fabricated CMs showed a good electrical conductivity of 1.58×102 S cm–1 and a very low surface roughness.

금속나노입자는 진단이나 치료를 포함한 의생명응용분야에 있어 매력적인 특징들을 갖고 있다. 양성자 빔 치료를 위한 방사선증감제로 사용하기 위해 가교덱스트란이 코팅된 산화철나노입자(SPIONs)와 실리카가 코팅된 산화가돌리늄나노입자(SPGONs)를 합성하였다. 덱스트란과 실리카는 각각 SPIONs와 SPGONs의 보호수단이다. 합성된 SPIONs와 SPGONs를 투과전자현미경(TEM)으로 분석한 결과 각각 평균 직경이 3~5 nm와 30~100 nm였다. 합성된 방사선 증감제의 효과를 평가하기 위해 세포생존곡선 측정과 Western blotting을 수행하였다. 측정된 세포생존곡선으로부터 계산된 90% 세포사멸 시 방사선증감비는 SPIONs와 SPGONs에 대하여 각각 1.23과 1.03이었다. Western blotting 결과 역시 Cytochrome C의 발현량이 SPIONs를 처리한 암세포에서 유의적으로 증가됨을 보였다.

The study was carried out to determine the gel pasting properties of barley (Hordeum vulgare L. cv. Geoncheonheugbori) as affected by different proton beam irradiation. The λmax, blue value, and amylose content were significantly associated with increasing proton beam irradiation. The pasting time in barley flour irradiated with proton beam ranged 0.09 to 0.16 min shorter than nonirradiated barley flour. Gel pasting temperature ranged 57.4 to 60.5℃. Gel pasting temperature in barley flour decreased with increasing proton beam irradiation. Proton beam irradiation caused a significant decrease in the onset temperature (To), peak temperature (Tp), conclusion temperature (Tc) and enthalpy change (ΔH). Gelatinization range (R) in barley starch was more broaden than that of non-irradiated barley starch. Barley starches gave the strong diffraction peak at around 2θ values15°, 18°, 20°, and 23° 2θ. Peak intensity tended to increase with increased proton beam irradiation. The granule crystallinity is closely associated with decreased amylose and increased amylopectin component. The crystallinity degree of barley starch irradiated with proton beam was significantly increased and it ranged from 24.9 to 32.9% compared to the non-irradiated barley starches. It might be deduced that proton beam irradiation causes significant changes of properties of starch viscosity in rice, especially at high irradiation of proton beam.

본 연구는 초상자성 산화철 나노입자 (SPIONs)의 세포독성평가 및 SPIONs를 uptake한 뇌신경교종 (glioblastoma multiforme, GBM) 세포의 방사선 세포생존곡선을 구하기 위해 수행되었으며, 본 연구의 결과는 양성자선과 SPIONs 이용한 GBM의 양성자선 치료선량 정보 등 양성자선 치료효과를 개선하기 위한 기초자료로 활용될 수 있을 것이다.SPIONs의 세포독성을 평가는 in vitro 실험 후 MTT 분석법을 이용하여 수행하였다. 독성평가 결과 1~100μg/ml의 농도에서는 세포생존율의 유의한 차이가 나타나지 않았다. 하지만 200μg/ml의 농도에서는 세포생존율이 74.2%로 감소하며 세포독성을 나타냈다. SPIONs가 uptake 된 U373MG세포와 uptake 되지 않은 U373MG세포에 0~5 Gy의 양성자선을 조사하여 각각에 대한 세포생존곡선을 측정한 결과를 분석하여 SPIONs가 uptake된 U373MG세포의 세포생존율이 더 급격히 감소함을 알 수 있었다. 결론적으로 SPIONs가 uptake 된 세포에서는 보다 적은 선량으로도 세포사멸을유도할 수 있음을 알 수 있었다. 따라서 GBM에 SPIONs를 타겟팅하면 양성자선을 이용한 뇌신경교종 치료효과를 개선할 수 있음을 보였다.

Ionizing radiations have been effective mutagen to overcome the limitation of the useful genetic resources in natural environment. This study was conducted to investigate an effect of proton beam on germination, growth patterns in the irradiated dandelion (Taraxacum officinale), and genetic variation in 12 morphological mutants induced in proton-beam irradiated dandelion. Percentage germination rate was drastically decreased over 250Gy. The lethal dose 50 (LD50) of germination was estimated between 250 Gy to 500 Gy. Significant decreases in growth patterns (plant height, number of leaf and fresh weight) were observed by increase of dose (Gy) of proton beam irradiation. According to the correlation analysis between dosage and growth factors, the orders of compactness of correlation were germination, plant height, fresh weight and number of leaf, respectively. Twelve morphological variants such as, dwarf, color, plastid, growth and leaf shape were screened at 50 to 250 Gy of the beam irradiation. As a result of ISSR analysis of the 12 variants, out of 33 bands detected overall, 8 bands were identified to be polymorphic with a rate of 24.2% at the control group. While 33 bands detected overall, 21 bands were identified to be polymorphic with a rate of 63.6% at the proton beam irradiation. The result indicates that the dandelion with proton beam treatment might be promoted variation at DNA level

The study was carried out to evaluate the affect of proton beam radiation on production of bulbil and tuber including change of endogenous gibberellins, of Dioscorea opposita Thunb. The yield of bulbils and tubers from non- and irradiated D. opposita Thunb at doses of 5, 10, 15 and 20 Gy were determined. Endogenous gibberellins were also quantified by GC/MS analysis. D. opposita tubers irradiated at 15 Gy produced higher bulbil production than non-irradiated plants. Enlarged bulbil (above size diameter 4 mm) was significantly increased at 15 Gy. Bioactive endogenous GA4 was dominant in bulbils and tubers irradiated with proton beam rather than GA1 . Major gibberellins biosynthetic pathways in bulbils and tubers of D. opposita plants were non C-13 hydroxylation route. From the results of this study, 15 Gy proton beam radiation was suggested as an optimal dose that can produce high amounts of bulbil for mass production of D. opposita plant.

The survival rate and thermal, crystal, and physicochemical properties of starches in chinese yam tubers irradiated to proton beam were determined. Survival rate was decreased with increased proton beam irradiation. Amylose content of D. opposita starches from different proton beam ranged from 13.2% to 17.8%. D. opposita starch at 5 Gy showed the highest δHgel values (12.0 J/g) while D. opposita starch at 25 Gy showed the lowest values (10.1 J/g). Several parameters such as PKV (peak viscosity), HPV (Hot peak viscosity) and CPV (Cooling peak viscosity) decreased with the increase in irradiation dose. The degrees of crystallinity of the D. opposita starches at 5, 10, 15, 20 and 25 Gy were 37.2, 38.3, 38.9, 39.2 and 39.9%, respectively. It might be deduced that proton beam irradiation causes changes of starch, especially at high dose irradiation.

식물 20종을 메탄올로 추출하여 양성자 빔 조사 에너지양(1, 5, 10 KGray)에 따른 항산화 활성 능을 탐색 하고자 DPPH 라디칼 소거활성과 ABTS free 라디칼 소거 활성에 대하여 조사하였다. 양성자 빔 조사 시 15종류는 활성이 증가하였으나 10 KGray에서 흑축(Pharbitis nil Choisy)은 활성이 감소하였으며, 4종류는 활성변화가 없었다. DPPH 라디칼 소거활성은 1 및 5 KGray에서 유근피(Ulmus macrocarpa) (84 %), 10 KGray (85 %)로 가장 높았으나 10 KGray에서 흑축(Pharbitis nil Choisy)은 6 % 감소하였다. IC50값을 무처리구와 빔 조사량에 대한 활성을 비교하면 1 KGray 에서 산약(Dioscorea batatas Decne.) 6.3배, 5 KGray에서 천화분(Trichosanthes kirilowii Max.) 2.1배, 산약(Dioscorea bata-tas Decne.) 2.8배 증가하였다. ABTS free 라디칼 소거활성에서 1 KGray의 양성자 빔 에너지를 조사 했을 경우, 가자(Terminalia chebula Retzius)는 60 % 증가하였다. IC50값은 1 KGray 빔 조사 시 0 KGray보다 마황근(Ephedra sinica Stapf) 2.0배, 가자(Terminalia chebula Retz.) 2.5배, 우방자(Arctium lappa Linne) 2.4배 증가하였다.

Effects of proton beam irradiation on seed germination and growth pattern of tobacco (Nicotiana tabacum L. cv. BY-4; N. plumbaginifolia) and rice (Oryasativa L.) plants were estimated to develop the efficient conditions of irradiation. Seed germination rate was decreased by increasing the proton beam the current and the beam irradiation time in both tobacco and rice seeds. The beam irradiation conditions showing 50% germination were over 60 sec at 10 nA, approximately 5 sec at 100 nA and at 500 nA beam current in tobacco seeds. And the conditions of 50% germination were 60 sec at 10 nA, and 100 nA and 30 sec at 500nA in rice (cv. Dongjin 1) seeds. The growth of irradiated plants was decreased, but significant difference in morphological changes was not observed by the proton beam treatment. The proton beam is able to use as a mutagen, but some of the factors including beam size and beam detector-system must be established for efficient usage of the beam.