• Mass Spectrometry Letters
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• 제6권2호
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• pp.27-30
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• 2015

This article reviews the fundamentals of sample preparation used in matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS). MALDI is a soft ionization method used to generate analyte ions in their intact forms, which are then detected in MS analysis. MALDI-MS boasts fast analysis times and easy-to-use operation. The disadvantages of MALDI-MS include the occurrence of matrix-associated peaks and inhomogeneous distribution of analyte within the matrix. To overcome the disadvantages of MALDI-MS, various efforts have been directed such as using different matrices, novel matrix systems, various additives, and different sample preparation methods. These various efforts will be discussed in detail. This article will benefit those who would like to obtain basic knowledge of MALDI sample preparation and those who would like to use MALDI-MS in their chemical analyses.

• Mass Spectrometry Letters
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• 제15권1호
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• pp.62-68
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• 2024

The Suspension Trapping (S-Trap) method has been a prominent sample preparation technique since its introduction in 2014. Its capacity to induce protein aggregation using organic solvents has significantly improved protein purification and facilitated peptide identification. However, its full potential for automation has been limited by the lack of a suitable liquid handling system until recently. In this study, we aimed to enhance the automation of S-Trap sample preparation by optimizing the S-Trap digestion process, incorporating triethylammonium bicarbonate (TEAB) and CaCl₂. The utilization of TEAB buffer conditions in this innovative process led to a noteworthy 12% improvement in protein identification. Additionally, through careful observation of various incubation conditions, we streamlined the entire sample preparation workflow into a concise 4 hours timeline, covering reduction, alkylation, and trypsin incubation stages. This refined and expedited automated S-Trap digestion process not only showcased exceptional time efficiency but also improved trypsin digestion, resulting in increased protein identification.

• 한국생산제조학회지
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• 제6권3호
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• pp.52-57
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• 1997

Electronic Speckle Pattern Interferometry(ESPI) using the Model 95 Ar. laser, a video system and an image processor was applied to the in-plane displacement measurements. Unlike traditional strain gauges or Moire method, ESPI method requires no special surface preparation or attachments and can be measured in-plane displacement with no special surface preparation or attachments and can be measured in-plane displacement with no contact and real time. In this experiment specimen was loaded in parallel with a loadcell. The specimen was the cold rolled steel sheet of 2mm thickness, which was attached strain gauges. The study provides an example of how ESPI have been used to measure strain displacement in this specimen. The results measured by ESPI compare with the data which was measured by strain gauge method in tensile testing.

• Archives of Pharmacal Research
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• 제29권10호
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• pp.921-927
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• 2006

Prolonged release micro particles of clarithromycin (CL) were prepared using Eudragit RL 100 and RS 100 by spray-drying and casting-drying techniques. For the characterization of those microparticles, preparation yield, particle size distribution, X-ray diffraction, thermal behavior, active agent content and in vitro dissolution from the microparticles were performed. HPLC was used for the assay of clarithromycin and the assay method was validated. All the formulations obtained showed prolonged release when compared to pure clarithromycin. Microparticles prepared by spray-drying method had a slower release compared to those of casting drying method. Spray-drying method seems to be a more suitable method to prepare microparticles for prolongation in release.

• Mass Spectrometry Letters
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• 제14권4호
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• pp.178-185
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• 2023

QuEChERS is used worldwide as a universal sample preparation method with many benefits, such as being quick, easy, cheap, effective, rugged and safe. This study examined whether QuEChERS can be employed in isotope dilution mass spectrometry (ID-MS) for accurate analysis of pesticides in food. The ratios of fortified values and measured values of malathion and fenitrothion using the QuEChERS method were compared with those using the solid phase extract (SPE) method which was previously used in this laboratory. The separations of the two pesticides on DB-5MS and VF-1701MS columns were compared. Malathion and fenitrothion were fortified into kimchi cabbage and pretreated with the QuEChERS method and the SPE method. The results obtained using the DB-5MS column varied according to the sample preparation method, column and pesticide level. Using the VF-1701 column, ratios were 98-102% by both QuEChERS and Carb/NH₂ SPE method for all fortification level. Malathion and fenitrothion were fortified into strawberry samples for comparison with kimchi cabbage. The results for the strawberry samples indicated that the ratios were not influenced by the sample preparation methods or GC column. The QuEChERS method could be acceptable in the ID-MS method for pesticide residue analysis in food, however other conditions should be carefully considered for accurate determination, such as the column, amount of analyte and food matrix.

• 대한한의학회지
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• 제34권1호
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• pp.103-115
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• 2013

Objectives: This study proposes a new form of English translation in comparison with that shown in English books related to Sasang Constitutional medicine formulae which have been published up to now. Methods: This study formulated a new form of English translation guidelines by making a comparative analysis of the English translation cases listed in "Korean-English Dictionary of Oriental Medicine", "Longevity and Life Preservation in Eastern Medicine", and "Introduction to Sasang Constitutional Medicine". Results: This study as a common rules suggested that names of preparation form should be placed at the very end of the formula name and the first letters of the major words of the formula name should be capitalized. In addition, for the sake of accuracy in English translation of the formula name, this study divided the formula names into 8 types. The 8 sorts of types include: (a) Materia Medica + Preparation Form, (b) Materia Medica + Indication + Preparation Form, (c) Materia Medica Numbers + Preparation Form, (d) Indication + Preparation Form, (e) Concept + Preparation Form, (f) Concept + Materia Medica + Preparation Form, (g) Concept + Indication + Preparation Form, (h) Etcetera. In these types, medicinal herbs should be written in scientific name, and translation of indication can follow Noun+~ing participle form. In case of the terms having a Korean-medicine-based meaning, this study aimed for source-oriented translation. Conclusions: This study provides a general English translation method and examples of the formula names for Sasang constitutional medicine.

• Korean Chemical Engineering Research
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• 제53권3호
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• pp.372-381
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• 2015

본 연구에서는 $Ni/Al_2O_3$ 촉매를 사용한 에틸렌글리콜의 수증기 개질반응에서 제조 방법에 따른 영향을 알아보았다. 촉매들은 건식 함침법, 습식 함침법 그리고 공침법을 사용하여 제조하였다. 공침법을 사용하여 촉매 제조시 침전제를 KOH, $K_2CO_3$, $NH_4OH$를 각각 사용하여 침전제에 따른 영향 또한 알아보았다. 제조한 촉매들은 질소 물리흡착, 유도결합 플라즈마 질량분석법(ICP-AES), X선 회절법(XRD), 수소 승온 환원법(TPR), 수소 화학흡착, 승온 산화법(TPO), 주사전자현미경(SEM), 열분석법(TGA)을 사용하여 촉매의 물리화학적인 특성을 분석하였다. 773 K에서 환원한 촉매의 경우 KOH 혹은 $K_2CO_3$를 침전제로 사용하여 공침법으로 제조한 촉매가 가장 높은 활성을 보였다. 촉매 제조 방법은 Ni의 입자크기, Ni 산화물의 환원도, 반응에서의 활성과 안정성, 반응 중 탄소 침적의 형태 등에 영향을 끼치는 것을 확인할 수 있었다. KOH를 침전제로 사용하여 공침법으로 제조한 촉매의 경우 환원온도를 773~1173 K까지 증가시켰을 때, Ni 입자크기의 증가에도 불구하고 Ni 산화물의 환원도가 증가하므로 반응활성이 증가하는 것으로 나타났다.

• 생약학회지
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• 제41권1호
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• pp.48-53
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• 2010

GCSB-5 preparation is a purified extract from a mixture of 6 medicinal plants(Acanthopanacis Cortex, Achyranthis Radix, Saposhnikoviae Radix, Cibotii Rhizoma, Glycine Semen Nigra, Eucommiae Cortex) that have been widely used for the treatment of various bone disorders. The aim of this study was to investigate HPLC analysis method and screening of standard compound on Cibotii Rhizoma for quality standardization of a medicinal crude drug GCSB-5. Onitin-4-O-$\beta$-D-glucopyranoside was isolated from Cibotii Rhizoma as the standard compound and identified on the basis of spectroscopic data such as NMR. HPLC analysis method for the determination of onitin-4-O-$\beta$-D-glucopyranoside was established for the quality control of the medicinal plants of Cibotii Rhizoma species, GCSB-5 raw material and GCSB-5 preparation. And validation of HPLC analysis methods were conformed for verification of HPLC methods by check to specificity, linearity, intra-day precision, inter-day precision and accuracy following ICH guideline.

• 한국대기환경학회지
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• 제20권2호
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• pp.185-193
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• 2004

A catalyst with CuO ceramic filter for simultaneous treatment of dust and HAP was prepared and characterized. Catalytic ceramic filter can not only potentially achieve the substantial savings in energy but provide with effective optimization and integration of process for simultaneous removal of SO$_2$, NO$_{x}$ and particulates from flue gases. Catalytic ceramic filters remove simultaneously particulates on exterior surface of filters and reduce NO to $N_2$ and $H_2O$ by SCR (Selective Catalytic Reduction) process. Preparation of catalyst impregnated ceramic filter with disk shape (Ψ 50) follow the processing of alumino-silicate ceramic filter, support impregnation and catalyst impregnation (copper oxide). Preparation routes of alumino-silicate catalyst carrier suitable for production of catalytic filters practically were studied and developed using the sol-gel and colloidal processing, homogeneous precipitation and impregnation method. Characterization of the catalyst, catalyst carrier catalytic filter materials have been performed the using various techniques such as BET, XRD, TGA, SEM. Combination of the sol-gel and colloidal processing and impregnation method is recommended to prepare catalyst carriers economically for catalytic filter applications.s.

• Journal of Pharmaceutical Investigation
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• 제31권4호
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• pp.257-263
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• 2001

The microspheres have been developed as a new drug delivery system. Although many particulate drug carriers, such as liposome, niosome and emulsion, have been introduced, injectable and biodegradable microspheres appears to be a particularly ideal delivery system because the local anesthesia is not necessary for the insertion of large implants and for the removal of the device after the drug release is finished. Biodegradable microspheres with nicotine and triamcinolone acetonide are prepared and evaluated. As biodegradible polymers, PLA (M.W. 15,000, PLA-0015), PLGA (M.W. 17,000, RG 502) and PLGA (M.W. 8,600, RG 502H) are used. This study attempted to prepare and evaluate the nicotine and triamcinolone acetonide-incorporated microspheres, which were prepared by two methods, solvent-evaporation and spray-drying methods. The microspheres, as a disperse system for injections, were evaluated by particle size, size distribution, entrapment efficiency, and in vitro drug release patterns. The differences of preparation method, partition coefficient, types of polymer, and preparation conditions of microspheres influence the particle size, entrapment efficiency, and in vitro drug release patterns.