• 한국식품과학회지
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• 제36권3호
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• pp.490-500
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• 2004

탈지강에 10% ethanol을 5배(w/v) 첨가하여 pH 8로 조절하면서 3시간 동안 추출한 탈지강 단백질 추출액에 glycerol 2% (w/v)을 첨가하여 $80^{\circ}C$까지 가열한 후, 냉각된 코팅제를 현미에 코팅, 건조하여 코팅쌀을 가공하였다. 코팅 횟수는 1-5회로 코팅현미를 8주간 저장하면서 품질변화를 관찰하였다. 중량 감소율은 큰 변화가 없었고, 과산화물가, 산가는 코팅쌀이 코팅하지 않은 쌀 보다 낮았다. Lipase와 lipoxygenase의 활성은 코팅횟수가 3회 이상부터는 효소의 활성이 약간 감소하였고, 코팅에 따른 쌀의 표면과 내부를 주사전자현미경으로 확대하였을 때 모든 시료에서 미립현상을 관찰할 수 있었으며, 수화속도는 큰 차이가 없었다. 물결합력은 코팅쌀이 코팅하지 않은 쌀보다 높았고, 호화 응집성의 감소율도 3회 이상 코팅한 쌀이 훨씬 작았으며 쌀의 전분호화개시온도는 각각 $68^{\circ}C$와 $71^{\circ}C$, 최고 점도는 320BU와 420BU였다. 저장기간 동안 쌀의 갈변에 영향을 끼치는 색도인 b값은 코팅한 쌀이 코팅하지 않은 쌀보다 낮았으며, 물리적 조직감에서는 코팅한 쌀이 경도가 낮고 부착성이 높았다. 저장 8주 후 취반하여 관능검사를 실시한 결과, 전반적인 품질 항목에서 코팅쌀의 기호도가 높았다.

• Journal of Pharmaceutical Investigation
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• 제36권2호
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• pp.89-95
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• 2006

A selective and sensitive reversed-phase HPLC method for the determination of pentoxifylline in human serum was developed, validated, and applied to the pharmacokinetic study of pentoxifylline. Pentoxifylline and internal standard, chloramphenicol, were extracted from the serum by liquid-liquid extraction with dichloromethane and analyzed on a Luna CI8(2) column with the mobile phase of acetonitrile-0.034 M phosphoric acid (25:75, v/v, adjusted to pH 4.0 with 10 M NaOH). Detection wavelength of 273 nm and flow rate of 0.8 mL/min were used. This method showed linear response over the concentration range of 10-500 ng/mL with correlation coefficients greater than 0.999. The lower limit of quantification using 0.5 mL of the serum was 10 ng/mL, which was sensitive enough for pharmacokinetic studies of pentoxifylline. The overall accuracy of the quality control samples ranged from 89.3 to 92.7% for pentoxifylline with overall precision (% C.V.) being 4.1-9.2%. The relative mean recovery of pentoxifylline for human serum was 105.8%. Stability (stock solution, short and long-term) studies showed that pentoxifylline was not stable during storage. But three freeze-thaw cycles and extracted serum samples were stable. This method showed good ruggedness (within 15% C.V.) and was successfully applied for the analysis of pentoxifylline in human serum samples for the pharmacokinetic studies of orally administered $Trental^{\circledR}$ tablet (400 mg pentoxifylline), demonstrating the suitability of the method.

• 한국수산과학회지
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• 제28권5호
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• pp.569-576
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• 1995

훈제 굴 통조림의 가열살균기준 설정을 위하여 $105^{\circ}C\;-\;115^{\circ}C$의 온도범위에서 Fo-값을 달리하여 살균한 제품을 $5^{\circ}C\;-\;50^{\circ}C$의 서로 다른 온도에 저장하면서 품질의 안전성을 검토하였다. $110^{\circ}C$에서 Fo-값 5.92분 이상으로 살균한 제품은 6개월 동안의 저장에도 pH, 아미노질소의 양, 산가, 그리고 TBA-값에 거의 변화가 없었다. 온도 $105^{\circ}C$ 및 $115^{\circ}C$에서 Fo-값 $5.50\pm0.1$분 및 $6.50\pm0.1$분으로 살균하여 4개월 저장한 제품에서도 같은 결과를 확인하였다. 그러나 온도 $110^{\circ}C$에서 Fo-값 5.92분 미만으로 열처리한 제품에서는 품질변화가 심하게 일어남이 확인되었다. 따라서 훈제 굴 통조림의 가열살균기준으로서는 Fo-값 6.0분이 적당한 것으로 판단되었다.

• Bulletin of the Korean Chemical Society
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• 제32권8호
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• pp.2648-2656
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• 2011

A simple HPLC-DAD method was developed and validated to determine B group vitamin content (thiamine, riboflavin, nicotinamide, pantothenic acid, pyridoxine and folic acid) in supplemented food samples, i.e., infant formula, cereal, low-calorie food, a multi-vitamin pill and a vitamin drink. In this study, the most significant advantages were simultaneous determination of the six B group vitamins in various food matrices and a small number of sample treatment steps that required only an organic solvent, acetonitrile. Moreover, this method prevents reduction of column durability, because the mobile phase does not contain ion-pairing reagents. Analytes were separated on a Develosil RPAQUEOUS $C_{30}$ (4.6 mm ${\times}$ 250 mm, 5 ${\mu}M$ particle size) column with a gradient elution of acetonitrile and 20 mM phosphate buffer (pH 3.0) at a flow rate between 0.8 and 1.0 mL/min. Detection was performed at 275 nm, except for that of pantothenic acid (205 nm). The calibration curves for all six vitamins showed good linearity with correlation coefficients ($r^2$) higher than 0.995. The developed method was validated with respect to linearity, intra- and inter-day accuracy and precision, limit of quantification (LOQ), recovery and stability. The method showed good precision and accuracy, with intra- and inter-assay coefficients of variation less than 15% at all concentrations. The recovery was carried out according to the standard addition procedure, with yields ranging from 89.8 to 104.4%. This method was successfully applied to the determination of vitamin B groups in supplemented food products.

• 한국지반신소재학회논문집
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• 제10권2호
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• pp.67-72
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• 2011

광산배수슬러지는 산성광산배수를 물리 화학적 혹은 전기적으로 정화할 때 주로 생성된다. 여러 분야에서 광산배수슬러지의 재활용 가능성을 연구하는 것은 중요한 일이다. 본 연구에서는 매립지 폐기물인 광산배수슬러지를 차수재와 복토재로의 재활용 적용성을 평가하였다. 두 part로 구성된 본 논문의 Part 1에서는, 광산배수슬러지, 차수재 형성을 위해 혼합 한 벤토나이트와 시멘트의 물리 화학적 성질을 pH 측정 및 XRD, XRF, FESEM로 분석하였다. 회분식 시험을 통하여 광산배수슬러지를 벤토나이트, 시멘트와 혼합하고 다짐도, 투수시험 및 일축시험을 통하여 최적혼합배율을 광산배수슬러지 1 : 벤토나이트 0.5 : 시멘트 0.3으로 결정하였다. 광산배수슬러지의 초기 투수계수는 $7.10{\times}10^{-7}cm/s$이었다. 광산배수슬러지는 유해물 용출시험을 통하여 환경에 안전하다는 것이 확인되었다. 본 논문의 Part 2에서는 라이시미터 (Lysimeter)를 사용하여 계절변화와 강우조건에 따른 하절기 건조/습윤 및 동절기 동결/융해의 과정을 통해 광산배수슬러지를 이용한 차수재 사용시 환경 적용성 가능성 및 안정성을 고찰하고자 하였다.

• 청정기술
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• 제23권4호
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• pp.401-407
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• 2017

본 연구에서 아카시아꽃잎을 기질로 미백효과와 항산화효과가 우수한 천연물질을 생산하는 플라스크 발효법을 개발하였다. 아카시아꽃잎 추출액은 tyrosinase 활성을 저해하지 않은 반면, 2년 전통발효액과 2년 전통발효액을 접종한 아카시아꽃잎 플라스크 발효액은 tyrosinase 활성을 저해하였다. 아카시아꽃잎 플라스크 발효농축액 10% 포함된 용액의 tyrosinase 활성 저해율은 40%였고 농축액 함량이 증가할수록 저해율도 증가하였다. 양성대조군인 알부틴($20mg\;mL^{-1}$)과 코직산($80{\mu}g\;mL^{-1}$)의 tyrosinase 활성 저해율은 각각 90%와 58%였다. 이는 플라스크 발효농축액 40%가 포함된 용액의 미백성능이 코직산($80{\mu}g\;mL^{-1}$)의 성능과 비슷함을 보여준다. 농축액이 20% 포함된 용액의 항산화활성은 56%였고 농도가 증가할수록 용액의 항산화활성도 점차 증가하여 농축액이 60% 포함된 용액의 항산화활성은 98%였다. 이는 항산화효과가 우수한 비타민 C 수용액($10mg\;mL^{-1}$)과 동일한 항산화능력이다. 모든 농도의 발효농축용액에서 95% 이상의 세포생존율을 나타내어 발효액은 독성이 없는 것으로 판명되었다. 실온에 보관된 아카시아꽃잎 발효상등액은 pH와 당도 변화가 없었고 분리, 변색, 및 변취 등의 관능적 성상의 변화가 없는 안정한 상태를 유지하였다. 본 결과는 아카시아꽃잎 플라스크 발효액이 안전하고 미백 및 항산화효과가 뛰어나 미백화장품 원료로 사용가능함을 보여준다. 이는 본 연구를 통하여 아카시아꽃잎 발효기간을 획기적으로 단축시킨 배양방법이 개발되었음을 시사한다.

• 대한수의학회지
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• 제44권1호
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• pp.15-21
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• 2004

This paper describes the development of $^{99m}Tc$ tricarbonyl cysteine as potential renal function diagnostic radiopharmaceutical and evaluation of its biological characteristics using experimental animals. l-Cysteine was labeled efficiently with $^{99m}Tc$ tricarbonyl precursor $([^{99m}Tc(CO)_3(H_2O)_3)]^{+})$ under 30 min heating at ${75^{\circ}C}$. Labeling yield and stability were analyzed by high performance liquid chromatography (HPLC). The biodistribution property of $^{99m}Tc$ tricarbonyl cysteine in mice and its dynamic imaging profiles in rabbits were carried out. To investigate the excretion mechanism of $^{99m}Tc$ tricarbonyl cysteine, tubular transport inhibition test with probenecid was adopted. $^{99m}Tc$ tricarbonyl cysteine was obtained with a high labeling yield under the moderate condition. The results of biodistribution experiments of $^{99m}Tc$ tricarbonyl cysteine in ICR mice at 3 and 90 min provided that $^{99m}Tc$ tricarbonyl cysteine was very highly accumulated in the kidney and bladder, thereby almost 99% of $^{99m}Tc$ tricarbonyl cysteine was excreted within 90 min post injection. The same results were confirmed by the whole body dynamic images for 30 minutes and static images in rabbits at given time intervals after injection. Renogram of $^{99m}Tc$ tricarbonyl cysteine in rabbits showed that its $T_{max}$ and $T_{1/2}$ of $^{99m}Tc$ tricarbonyl cysteine were $2.33{\pm}0.56$ and $4.30{\pm}0.79$ min, respectively. The $T_{max}$ of $^{99m}Tc$ tricarbonyl cysteine with probenecid pretreatment was $2.30{\pm}0.17$ min, whereas $T_{1/2}$ of that with probenecid pretreatment was $17.0{\pm}32.47$ min. $T_{1/2}$ of $^{99m}Tc$ tricarbonyl cysteine with probenecid pretreatment was significantly different, as compared to the result without probenecid (p<0.0001). The results showed that the excretion of $^{99m}Tc$ tricarbonyl cysteine was extremely affected by probenecid. Therefore, $^{99m}Tc$ tricarbonyl cysteine was rapidly excreted from the kidney principally by the tubular secretion.

• 한국수산과학회지
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• 제24권2호
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• pp.137-143
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• 1991

정어리를 비교적 간단한 방법으로 식품가공용 중간소재로 이용하기 위한 일련의 연구로서 정어리육을 채취하여 autoclave$(121^{\circ}C,\;15Lbs)$에서 처리한 다음 압착 및 알칼리용액을 분무시킨 후 이를 건조 및 분쇄하여 정어리 어육 농축 단백질을 제조하였다. 고온가압처리 시간은 $121^{\circ}C$에서 1분, pH는 7.8로 하여 제조하는 것이 가장 적당하였다. 이렇게 제조된 제품의 단백질함량은 $74.4\%$, 지방함량은$9.1\%$였다. 또한 수율은 $40.0\%$로 자숙처리한 제품이나 에탄올 처리한 제품보다 높았고, 유화성 및 보수력은 각각 $48.7\%,\;50.0\%$ 였다 포말성을 $44\%$로 낮았으며, 포말안정성도 $1{\~}2$시간으로 낮았다. 소화율은 $78.2\%$로 자숙처리제품(B) 및 에탄올처리제품(C)와 큰 차이가 없었으나, 소화된 성분의 관능검사 결과 고온가압처리제품(A)가 감칠맛이 가장 강한 것으로 나타났다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.362-362
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• 2014

Atomic layer deposition (ALD) can be regarded as a special variation of the chemical vapor deposition method for reducing film thickness. ALD is based on sequential self-limiting reactions from the gas phase to produce thin films and over-layers in the nanometer scale with perfect conformality and process controllability. These characteristics make ALD an important film deposition technique for nanoelectronics. Tantalum pentoxide ($Ta_2O_5$) has a number of applications in optics and electronics due to its superior properties, such as thermal and chemical stability, high refractive index (>2.0), low absorption in near-UV to IR regions, and high-k. In particular, the dielectric constant of amorphous $Ta_2O_5$ is typically close to 25. Accordingly, $Ta_2O_5$ has been extensively studied in various electronics such as metal oxide semiconductor field-effect transistors (FET), organic FET, dynamic random access memories (RAM), resistance RAM, etc. In this experiment, the variations of chemical and interfacial state during the growth of $Ta_2O_5$ films on the Si substrate by ALD was investigated using in-situ synchrotron radiation photoemission spectroscopy. A newly synthesized liquid precursor $Ta(N^tBu)(dmamp)_2$ Me was used as the metal precursor, with Ar as a purging gas and $H_2O$ as the oxidant source. The core-level spectra of Si 2p, Ta 4f, and O 1s revealed that Ta suboxide and Si dioxide were formed at the initial stages of $Ta_2O_5$ growth. However, the Ta suboxide states almost disappeared as the ALD cycles progressed. Consequently, the $Ta^{5+}$ state, which corresponds with the stoichiometric $Ta_2O_5$, only appeared after 4.0 cycles. Additionally, tantalum silicide was not detected at the interfacial states between $Ta_2O_5$ and Si. The measured valence band offset value between $Ta_2O_5$ and the Si substrate was 3.08 eV after 2.5 cycles.

• Macromolecular Research
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• 제13권3호
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• pp.167-175
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• 2005

This review explores recent works involving the use of the self-assembled nanoparticles of bile acid-modified glycol chitosans (BGCs) as a new drug carrier for cancer therapy. BGC nanoparticles were produced by chemically grafting different bile acids through the use of l-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC). The precise control of the size, structure, and hydrophobicity of the various BGC nanoparticles could be achieved by grafting different amounts of bile acids. The BGC nanoparticles so produced formed nanoparticles ranging in size from 210 to 850 nm in phosphate-buffered saline (PBS, pH=7.4), which exhibited substantially lower critical aggregation concentrations (0.038-0.260 mg/mL) than those of other low-molecular-weight surfactants, indicating that they possess high thermodynamic stability. The SOC nanoparticles could encapsulate small molecular peptides and hydrophobic anticancer drugs with a high loading efficiency and release them in a sustained manner. This review also highlights the biodistribution of the BGC nanoparticles, in order to demonstrate their accumulation in the tumor tissue, by utilizing the enhanced permeability and retention (EPR) effect. The different approaches used to optimize the delivery of drugs to treat cancer are also described in the last section.