• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.116-116
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• 1997

Complex formation of practically insoluble dexamethasone dipropionate (DDP) with ${\beta}$-cyclodextrin (${\beta}$-CD), dimethyl-${\beta}$-cyclodextrin (DMCD), trimethyl-${\beta}$-cyclodextrin (TMCD), 2-hydroxypropyl-${\beta}$-cyclodextrin (HPCD) and sulfobutyl ether ${\beta}$-cyclodextrin (SBCD) in water was investigated by solubility method at various temperatures. Water solubility of DDP was found to be 1.78 $\mu\textrm{g}$/$m\ell$ at 37$^{\circ}C$. Propylene glycol (PG)-water cosolvent increased the solubility of DDP, but the solubilization was not sufficient (8.93 $\mu\textrm{g}$/$m\ell$ in 20% PG). The addition of CD markedly increased the solubility of DDP in water, and A$\sub$L/ type phase solubility diagrams were obtained with ${\beta}$-CD, TMCD, HPCD and SBCD, where the apparent stability constants of the soluble complexes at 25$^{\circ}C$ were determined to be 1388, 216, 1054, and 1992 M$\^$-1/, respectively. However, DMCD remarkably increased the solubility of DDP, and showed an A$\sub$P/ type diagram, suggesting that DMCD forms a soluble complex of high order with DDP. The stability constant for the DDP-DMCD complex at 25$^{\circ}C$ was determined to be 19132 M$\^$-1/. The thermodynamic parameters were calculated for the inclusion complex formation in aqueous solution. CD (1${\times}$10$\^$-2/M) remarkably decreased the partition coefficients of DDP between isopropyl myristate/water in the order of TMCD < ${\beta}$-CD < HPCD < SBCD < DMCD, and in squalane/water system in the order of HPCD < TMCD < ${\beta}$-CD < DMCD < DMCD $\leq$ SBCD. This finding represents that, in a o/w type cream, cyclodextrin complexation with DDP may result in high concentration of DDP in aqueous phase. The permeation of DDP through a cellophane membrane was highly suppressed by the addition of CD, and the degree of suppression was different among CDs, indicating that CD may control the skin permeation of DDP. The dissolution rates of solid dispersions with CDs were much faster than those of drugs alone and corresponding physical mixtures. All DDP-CD solid dispersions exceeded the equilibrium solubility. Consequently these results suggest that complex formation of DDP with CDs may provide useful means to markedly enhance the solubility, and CDs are useful in the semi-solid preparations such as creams and gels for topical application.

• 한국식품영양학회지
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• 제26권4호
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• pp.706-712
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• 2013

음청류에 이용할 수 있는 오미자 추출액을 얻기 위해 증류수, 수돗물과 Ca, Mg 등의 미네랄이 풍부한 청송약수를 이용하여 오미자 추출액을 제조하고 이화화적 특성을 측정하였다. 오미자 추출조건으로는 25배의 용매비로써 실온에서 6, 9, 12, 15시간, $65^{\circ}C$에서 2, 3, 6, 9시간 동안 추출하였다. 추출용액의 명도(L, Lightness), 적색도(a, redness), 황색도(b, yellowness), 가용성 고형분(solid content), 산도(acidity), pH, DPPH 라디칼을 소거능을 이용한 전자 공여능(Electron Donating Ability, EDA)으로부터 전반적으로 양호한 추출조건을 구한 결과는 다음과 같다. 실온에서는 물의 종류에 상관없이 12시간 추출하는 것이 적당하였으며, $65^{\circ}C$ 가온 상태에서는 6시간 추출함이 적합함을 알 수 있었다. 가온 상태에서 약수의 경우 증류수, 수돗물에 비해 빠른 추출이 가능하였으며, 추출 시간이 증가함에 따라 산도는 낮아지나, 고형분의 양과 DPPH 라디칼을 소거능은 증가하였다. 전반적으로 고려할 때에 오미자 추출을 위한 가장 적합한 물로는 미네랄이 풍부한 약수이며, 다음으로 수돗물 그리고 증류수 순서임을 알 수 있다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1127-1127
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• 2001

The transfer of predictive models using various chemometric techniques has been reported for FTNIR and scanning-grating based NIR instruments with respect relatively dry samples (<10% water). Some of the currently used transfer techniques include slope and bias correction (SBC), direct standardization (DS), piecewise direct standardization (PDS), orthogonal signal correction (OSC), finite impulse transform (FIR) and wavelet transform (WT) and application of neural networks. In a previous study (Greensill et at., 2001) on calibration transfer for wet samples (intact melons) across silicon diode array instrumentation, we reported on the performance of various techniques (SBC, DS, PDS, double window PDS (DWPDS), OSC, FIR, WT, a simple photometric response correction and wavelength interpolative method and a model updating method) in terms of RMSEP and Fearns criterion for comparison of RMSEP. In the current study, we compare these melon transfer results to a similar study employing pairs of spectrometers for non-invasive prediction of soluble solid content of peaches.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.616-620
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• 2001

The objectives of this study are to investigate the suitability of various coal fly ashes and incineration ashes for zeolite synthesis. Zeolite P and hydroxysodalite are produced from coal fly ash and paper sludge incineration ash. When soluble and acid-soluble materials in incineration fly ash are removed by the water washing or acid washing before hydrothermal synthesis, hydroxysodalite can be produced. The factors to make solid-liquid separation difficult are the calcium component and the unburned carbon in ash.

• 한국분말재료학회지
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• 제30권4호
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• pp.305-309
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• 2023

This study aims to prepare a colloidal silica-containing powder to enhance the solubility and dissolution rate of rivaroxaban using a self-nanoemulsifying drug delivery system (SNEDDS). We investigate the impact of colloidal silica on a nanoemulsion system for preparing powdered SNEDDS. The liquid SNEDDS comprises 30/20/50 (w/w/w) Peceol/Cremophor RH40/Tween 80, which results in the formation of the smallest droplets. Three powdered SNEDDS formulations are prepared by suspending the liquid SNEDDS formulation using colloidal silica and spray drying. The powdered SNEDDS prepared with liquid SNEDDS and colloidal silica at a ratio of 1/0.5 (w/w) exhibits the highest water solubility (0.94 ± 0.62 vs. 26.70 ± 1.81 ㎍/mL) and dissolution rate (38.4 ± 3.6 vs. 85.5 ± 3.4%, 45 min) when compared to the drug alone. Morphologically, the liquid SNEDDS is adsorbed onto colloidal silica and forms smaller particles. In conclusion, an SNEDDS containing rivaroxaban, prepared using colloidal silica, facilitates the creation of a nanoemulsion and enhances the water solubility of rivaroxaban. Accordingly, this technology holds significant potential for commercialization.

• Journal of Pharmaceutical Investigation
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• 제32권2호
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• pp.73-80
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• 2002

Cefuroxime axetil is a cephalosporin antibiotic having a high activity against a wide spectrum of Grampositive and Gram-negative microorganisms. It is a cephalosporin antibiotic which exist as 2 diastereoisomers: diastereoisomer A and B. It shows polymorphism of three forms: a crystalline form having a melting point of about $180^{\circ}C$, a substantially amorphous form having a high melting point of about $135^{\circ}C$ and a substantially amorphous form having a low melting point of about 70^{\circ}C$. The crystalline form of cefuroxime axetil is slightly soluble in water because diastereoisomer A has lower solubility than B in water. Substantially amorphous form of which there are no difference in solubility between diastereoisomer A and B has better solubility than crystalline form, but it forms a thicker gel than crystalline form upon contact with an aqueous medium. Based on this reason, cefuroxime axetil is not readily absorbable in the gastrointestinal tract, rendering its bioavailability on oral administration very low. The object of this study was to develop an improved non-crystalline cefuroxime axetil composition having a high physicochemical stability and bioavailability. A non-crystalline cefuroxime axetil solid dispersant showing no peak on a Differential Scanning Calorimetry (DSC) scan is prepared by dissolving cefuroxime axetil and a surfactant in an organic solvent; suspending a water-insoluble inorganic carrier in the resulting solution; and spray drying the resulting suspension to remove the organic solvent, said solid dispersant having an enhanced dissolution and stability of cefuroxime axetil and being useful for the preparation of a pharmaceutical composition for oral administration. Tablet was formulated with this cefuroxime axetil solid dispersant, disintegrants and other ingredients. It disintegrated and dissolved easily and dynamically in dissolution medium, so showed a good dissolution profile.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2557-2560
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• 2010

To assay for antioxidant capacity of natural products considered important in producing human health benefits, a practical and economical method using pellet techniques was developed. A standard visualizing reagent, 1,1diphenyl-2-picryl-hydrazyl (DPPH), was mixed with a water-miscible polyvinyl alcohol (PVA), serving as a solid phase support for the DPPH reagent. A DPPH pellet was prepared by dropping a small volume of the DPPH solution onto PET film, and drying in an oven. The PVA-based DPPH pellet was dissolved into water, in which the water-miscible PVA plays as a non-ionic surfactant to help the DPPH reagent to be dissolved into the solvent. Using the DPPH assay, the antioxidant capacity of water-soluble extracts of black soybean, barley, green tea, and green gram was examined. Among the natural products tested, green tea showed the highest antioxidant capacity. This PVA-based DPPH antioxidant assay can be further applied in the natural food, raw plant material, and health product inspection field.

• 대한화학회지
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• 제33권1호
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• pp.46-54
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• 1989

식품 및 비타민 제제중에 존재하는 지용성 비타민의 추출 및 동시 정량법을 검토하였다. 역상 액체크로마토그래피에 의한 지용성 비타민의 동시 분리 및 정량은 메탄올 : 물 = 95 : 5 이동상으로 Novapak $C_{18}$ 컬럼하에서 이루어졌다. 비타민의 검출에는 UV검출기를 사용하였으며 검출감도를 증가시키기 위하여 분석중 UV 검출파장을 각각의 비타민 용리시간에 따라 최대흡수 파장인 330, 265, 285 및 290nm로 변경하였다. 지용성 비타민의 분리 및 분석은 40분안에 완료되었다. 시료의 전처리에는 알카리 가수분해법과 효소가수분해법을 이용하였으며, 비타민의 추출은 액체-액체추출법과 액체-고체추출법을 이용하였다. 비타민 A,D, E 분석에는 알카리 가수분해법 및 효소가수분해법이 비타민 K 분석에는 효소가수분해법만이 좋은 결과를 나타냈으며, 비타민 추출에는 액체-액체 추출시 diethyl ether, pentane 및 n-hexane이, 액체-고체 추출시 silica 카트리지가 좋은 추출효과를 나타냈다.

• Preventive Nutrition and Food Science
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• 제12권3호
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• pp.185-189
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• 2007

Quality characteristics of kochujang prepared with strawberry puree (10, 20, and 30% on the total weight basis) were investigated after 30 and 300 days of storage. The moisture content of strawberry kochujang at 300 days was considerably higher than that of strawberry kochujang at 30 days and increasing strawberry content from 0 to 30% significantly increased moisture content of kochujang progressively (p<0.05). Water activity and titratable acidity also showed similar trends, but pH showed the reverse trend with the highest value in control at 30 days and the lowest value in 30% strawberry kochujang at 300 days. As the strawberry puree content increased, amino-nitrogen content consistently and correspondingly decreased. Amino-nitrogen content at 300 days was higher than that of strawberry kochujang at 30 days. Soluble solids content also showed a similar trend, but soluble solid content at 300 days was considerably lower than that of strawberry kochujang at 30 days. Reduction in soluble solids content with increasing strawberry concentration was more evident at 30 days than at 300 day.

• 한국식품영양과학회지
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• 제17권3호
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• pp.255-261
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• 1988

저염김치의 숙도조절과 가식기관의 연장을 목적으로 원료배추에 대하여 2%의 소금과 sodium malate buffer(SMB) 0.4%를 첨가하여 $20^{\circ}C$에서 숙성시키면서 pectin질의 변화를 조사하였다. SMB 첨가김치는 무첨가에 비하여 가식기간이 40시간 정도 연장되었고 맛 조직의 신선도 연화상태등에서 양호하였다. Alcohol insoluble solid(AIS)와 protopectin(PP)는 숙성에 따라 감소되었으며 SMB 첨가김치에서 감소율이 낮았고 pectic acid(PA)와 water soluble pectin(WSP)는 이와 반대로 숙성에 따라 증가되었는 데 증가율은 무첨가 김치에서 높았다. PP와 PA는 각각 hemicellulose로부터 유래된 hexose와 pentose를 함유하였으나 숙성 중에 감소하였고 감소율은 무첨가김치에서 높았다. 김치가 숙성됨에 따라 극성이 낮고 분자량이 극도로 높은 PP가 조직으로 용출되어 나온 반면 극성이 높은 저분자의 PP는 감소하는 경향을 나타내었는데 무첨가의 경우가 현저하였다.