• 분석과학
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• 제13권5호
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• pp.565-572
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• 2000

파장분산형 엑스선분광분석기에 의한 Xe의 전자탐침미세분석시 표준물질에 대해 기술하였다. 실험결과 순수금속 표준시편을 사용할 수 없는 Cs, I, Ba의 표준물질로는 Csl와 $BaCO_3$가 가장 적당한 것으로 나타났다. 빔전류량 10-30 nA에서 Csl, CsBr로부터 측정한 Cs의 엑스선 세기는 빔전류량에 비례하였다. PET 결정 사용시 In-Nd 원소들의 원자번호 대 엑스선 세기간의 직선성은 가속전압 25-30 kV 범위에서 직선회귀 계수 R=0.99 이상의 좋은 상관성을 보였다. 직선회귀식으로 구한 Xe의 엑스선 세기 표준값은 가속전압 25 kV에서 Te의 엑스선 세기 표준값 보다 1.095배 높게 나타났다.

• Journal of Pharmaceutical Investigation
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• 제24권2호
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• pp.57-65
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• 1994

To increase the dissolution rate of practically insoluble biphenyl dimethyl dicarboxylate (DDB), various solid dispersions were prepared with water soluble carriers, such as povidone (PVP K-30), poloxamer 407, sodium deoxycholate (SDC) and polyethylene glycol (PEG) 6000, at drug to carrier ratios of 1:3, 1:5 and 1:10 (w/w) by solvent or fusion method. Dissolution test was performed by the paddle method. The dissolution rate of DDB tablets (25 mg) on market was found to be very low (11.44, 9.02 and 6.42% at pH 1.2, 4.0 and 6.5 after 120 min, respectively). However, dissolution rates of DDB from various solid dispersions were very fast and reached supersaturation within 10 min. DDB-PEG 6000 solid dispersion appeared to be better in enhancing the in vitro dissolution rate than others. Furthermore, the incorporation of DDB and phosphatidylcholine (PC) into ${\beta}-cyclodextrin$ at ratios of 1:2:20, 1:5:20 and 1:10:20 resulted in a 4.9-, 11.2- and 19.6-fold increase in DDB dissolution after 120 min as compared with the pure drug, respectively. This might be attributed to the formation of lipid vesicles which entrapped a certain concentration of DDB during dissolution. On the other hand, the permeation of DDB through rabbit duodenal mucosa was examined using some enhancers such as SDC, sod. glycocholate (SGC) and glycyrrhizic acid ammonium salt (GAA). Only trace amounts of DDB were found to permeate through deuodenal mucosa in the absence of enhancer. SDC was found to markedly decrease the permeation flux of DDB, however, SGC and GAA (5 mM) enhanced the flux of DDB 1.6 and 2.4 times higher as compared with no additive, respectively.

• Journal of Pharmaceutical Investigation
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• 제6권3호
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• pp.48-57
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• 1976

An enhancement in the dissolution rate of the drug should facilitate its GI absorption if the absorption process is dissolution rate limited. One of the need for the techniques that can potentially enhance the dissolution rate and extent of absorption of hydrophobic drugs is the formation of coprecipitates with pharmacologically inert, polymeric materials. The physicochemical modification offers the advantage of possibly enabling one to administer the drug orally in a form from which it is most available for GI absorption. Several $investigation^{1-15)}$ demonstrated that the formation of solid dispersions or coprecipitates of relatively water-insoluble drugs with various pharmacologically inert carriers can increase singnificantly their in vitro dissolution rates. However, little information is available in the literature related to the dissolution rate patterns of furosemide, a water-insoluble diurectices, with respect to the sort of copolymer and the ratio of coprecipitates as a function of time, respectively. The purpose of the present investigation was to ascertain, the general applicability of the copolymers to use fore more fast, enhanced dissolution techniques of furosemide. To accomplish the need for enhancement in the dissolution rate of furosemide, varying ratio coprecipitates with different water-soluble polymers, such as polyvinylpyrrolidone (PVP), polyethylene glycol 4000(PEG 4000), and polyethylene glycol 6000 (PEG 6000), were quantitatively studied by comparing their dissolution characteristics of furosemide. The dissolution patterns of pure furosemide, varying ratio furosemide-PVP coprecipitates, (1:2, 1:5, and 1:9(w/w)), furosemide-PEG 4000 coprecipitates (1:4, 1:9, and 1:19(w/w), furosemide-PEG 6000 coprecipitates(1:4, 1:9, and 1:19(w/w)), and the same ratio physical mixtures, respectively, were compared by the amount dissolved as a function of time.

• Journal of Pharmaceutical Investigation
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• 제31권4호
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• pp.217-224
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• 2001

To develop a novel transdermal delivery system of loxoprofen (LP), a potent antiinflammatory and analgesic agent, the effects of various vehicles and penetration enhancers on the skin permeation of LP from solution formulations were investigated. The permeation rate of LP through excised guinea pig skin was measured using a side-by-side permeation system at $32^{\circ}C$. The solubilities of LP in various vehicles were determined by the equilibrium solubility method, and partition coefficients $(P_c)$ were determined. The solubility of LP increased in the rank order of water & isopropyl myristate (IPM) & glyceryl dicaprylate/dicaprate & propylene glycol dicaprylate/caprate & propylene glycol laurate (PGL) & polyethylene glycol 400 & diethylene glycol monoethyl ether (DGME) & ethanol. n-Octanol-water $P_c$ value was 15.5. Among pure vehicles tested, IPM and PGL showed highest fluxes of $89.9{\pm}5.0$ and $45.4{\pm}0.3\;{\mu}g/cm^2/hr$ from saturated solutions, respectively. However, it was not possible to demonstrate any correlation between the solubility of LP and its permeation rate, indicating the change in the barrier property of the skin and/or carrier mechanisms by vehicles tested. The addition of DGME to IPM or PGL markedly increased the solubility of LP, but the permeation rate did not decrease when the concentration of DGME in the cosolvent was increased upto 40%. The addition of linoleic acid (3%) in the cosolvent slightly increased the permeation rate, but others such as lauroyl sarcosine, fatty alcohols and fatty acids tested did not show enhancing effect. In conclusion, the DGME-IPM or DGME-PGL cosolvent system proved to be a good vehicle to enhance the skin permeation of LP.

• 분석과학
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• 제18권3호
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• pp.206-215
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• 2005

1929년부터 상업적으로 사용되기 시작한 폴리염화비페닐류(PCBs)는 Aroclor (미국), Kanechlor (일본), Sovol (러시아) 등 다양하게 상업적으로 시판되었다. PCBs는 209종의 동족체로 구성되어 있으며 변압기, 축전기의 절연유, 윤활유, 가소제, 도료, 복사지 등의 여러 용도로 사용되어 온 산업용 화학물질이다. 본 연구에서는 시판되는 PCBs Aroclor 제품을 구입하여, 표준물질을 사용하여 피크패턴법에 의한 정량방법과 계수비교법에 의한 정량방법을 비교하고, 시료에 적용하여 분석하였다. 분석대상 시료의 피크패턴은 Aroclor 1242:1254:1260의 세 종류가 혼합된 경우와, Aroclor 1242:1254, Aroclor 1254:1260이 혼합된 경우 그리고 Aroclor 1242, 1254 및 1260이 혼합된 시료가 다양한 비율로 검출되었다. 또한, 두 정량법에 따른 분석 결과는 혼합된 PCBs 제품의 종류가 한 종류인 경우 보다 여러 종류일수록 두 정량값의 차이가 없는 것으로 나타났다.

• 분석과학
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• 제6권1호
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• pp.39-45
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• 1993

시스-펩티드 모델 화합물인 디케토페라진을 수용액과 $D_2O$에서 320~218nm 사이의 여기 파장을 이용하여 라만 스펙트럼을 측정하였다. 본 연구는 공명 증폭되는 아미드 밴드를 명명하고, 그 증폭 메카니즘을 규명하는 데 목적이 있다. 3개의 공명 증폭된 시스-펩티드 표본밴드가 수용액 상태에서 1676, 1533, $806cm^{-1}$에서 관찰되었고, 이것을 각각 아미드, I, II, S 밴드로 명명하였다. $1533cm^{-1}$ 아미드 II 밴드는 수용액 상태의 공명 라만 스펙트럼에서 가장 큰 밴드였으며, 순수한 C-N 신축운동이며, N-H를 N-D로 치환한 결과 $1520cm^{-1}$로 이동되었다. 이 밴드는 아마도 단백질내에 존재하는 시스형 펩티드를 관찰할 수 있는 표본 밴드가 될 것으로 예상된다. 여기 주파수를 바꾸어 가며 얻은 라만 밴드 크기 변화와, Albrecht A-항 모델로부터 시스 펩티드 라만 밴드가 188nm 근방의 펩티드 ${\pi}-{\pi}^*$ 전자 전이에 의하여 공명 증폭됨을 증명하였다. 이러한 자료를 바탕으로 시스 펩티드 ${\pi}^*$ 들뜬 상태의 기하구조는 전자 바닥 상태와 비교하여 C-N 결합이 늘어난 형태일 것으로 제안하였다.

• 분석과학
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• 제29권6호
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• pp.300-304
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• 2016

폐지방산과 ethylenediamine 또는 N,N'-bis (2-hydroxyethyl)ethylenediamine으로부터 아스팔트 박리방지제를 합성하였다. FT-IR과 NMR을 이용하여 분석한 결과 아마이드결합의 생성 및 박리방지제의 합성이 성공적으로 수행되었음이 확인하였다. 합성된 여러 종류의 박리방지제의 접착특성은 접촉각과 BBS 시험을 통해 비교하였다. 접촉각 측정으로부터 에틸렌다이아민과 동물유지로부터 제조된 시료가 가장 소수성이 컸으며, BBS 시험으로부터 수분저항성도 94%로 가장 우수한 것으로 나타났다. 그러나 에틸렌다이아민과 폐식용유의 반응생성물이 수분처리 전과 후의 절대적인 접착력은 각각 약 3610 및 3227 kPa로 가장 우수하였다. 전반적으로 접착력은 ED의 반응생성물이 HEED의 반응생성물보다 우수하였으며, 폐식용유나 동물유지의 반응생성물들이 순수한 콩기름의 반응생성물들보다 우수하였다.

• Journal of Pharmaceutical Investigation
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• 제41권3호
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• pp.179-184
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• 2011

This study aimed to confirm the effect of molecular weight (MW) in solid dispersion of carvedilol with poly-vinylpyrrolidone (PVP) of various MW. Solid dispersion of carvedilol with PVP was prepared by spray-drying method. Scanning electron microscopy (SEM) was used to analyze the surface of solid dispersion samples. Differential scanning calorimetry (DSC) and X-ray diffraction (XRD) were used to analyze the crystalline of solid dispersion. Fourier transform infrared spectroscopy (FT-IR) was used to analyze the change of chemical structure characteristic of solid dispersion. DSC and XRD show that drug crystalline was changed. FT-IR revealed that chemical structure of solid dispersion comparing the chemical structure of drug was changed. The dissolution studies of solid dispersion presented at simulated gastric juice (pH 1.2). The dissolution rate of solid dispersion was dramatically enhanced than pure drug and the MW of PVP has an effect on the release property of carvedilol in solid dispersion. In conclusion, the present study has confirmed the effect of MW of PVP on release property of solid dispersion formulation of carvedilol with PVP.

• 한국전문물리치료학회지
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• 제22권4호
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• pp.62-70
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• 2015

The aims of the current study were to assess reliability of range of motion (ROM) measurement of glenohumeral internal rotation (GIR) with a pressure biofeedback stabilization (PBS) method and to compare the reliability between manual stabilization (MS) and the PBS method. In measurement of pure glenohumeral joint motion, scapular stabilization is necessary. The MS method in GIR ROM measurement was used to restrict scapular motion by pressing the palm of the tester's hand over the subject's clavicle, coracoid process, and humeral head. The PBS method was devised to maintain consistent pressure for scapular stabilization during GIR ROM measurement by using a pressure biofeedback unit. GIR ROM was measured by 2 different stabilization methods in 32 subjects with GIR deficit using a smartphone clinometer application. Repeated measurements were performed in two test sessions by two testers to confirm inter- and intra-rater reliability. After tester A performed measurements in test session 1, tester B's measurements were conducted one hour later on the same day to assess the inter-rater reliability and then tester A performed again measurements in test session 2 for confirming the intra-rater reliability. Intra-class correlation coefficient (ICC) (2,1) was applied to assess the inter-rater reliability and ICC (3,1) was applied to determine the intra-rater reliability of the two methods. In the PBS method, the intra-rater reliability was excellent (ICC=.91) and the inter-rater reliability was good (ICC=.84). The inter-rater and intra-rater reliability of the PBS method was higher than in the MS method. The PBS method could regulate manual scapular stabilization pressure in inter- and intra-rater measuring GIR ROM. Results of the current study recommend that the PBS method can provide reliable measurement data on GIR ROM.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2006년도 추계학술대회 및 정기총회
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• pp.24-28
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• 2006

Author have studies lichen flora of the most important ice-free areas of Continental Antarctic: Bunger Hills, and the vicinity of Prudz Bay (Larsemann Hills, and Radok Lake in Prince Charles Mountains). Totally 44 lichen species from 22 genera were reported for Bunger Hills and 50 lichen species from 22 genera and 10 families: Acarosporaceae, Lecanoraceae, Lecideaceae, Parmeliaceae, Pertusariaceae, Physciaceae, Rhizocarpaceae, Stereocaulaceae, Theloschistaceae, and Umbilicariaceaewere reported for the Prudz Bay Region. 20 lichen species were found in the region for the first time. Phytogeographic analysis indicated a relatively high proportion of species with bipolar distribution - about 50% of recorded lichen species. About 30% of lichens normally don't extend into maritime zone occurring in continental Antarctic only. The most common lichen families in the region are Buelliaceae, Lecanoraceae and Teloschistaceae. The water supply and not a temperature is the critical factor for lichens in the Continental Antarctic. Moisture appears to be supplied for lichens not only from snow-melt water but mainly from air. In Maritime Antarctic, due to high air humidity macrolichens form communities everywhere (Himantormia, Usnea and Umbilicaria). In oases of Continental Antarctic extensive sites are lacking in lichen cover, even if the ground is normally snow free. Lichens occur at humid sites with moisture which were brought by winds over the ice cap and poorly developed or absent in dry areas. Of particular significance for lichens are substrate characteristics, animals influence and salinity brought by wind in coastal areas. Most rich lichen vegetation developed in oases around nests of snow petrels, where the melt water is enriched by nutrients. In contrast, the most pure vegetation is on mobile sand and gravel and in salted coastal habitats.