• Korean Chemical Engineering Research
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• 제43권2호
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• pp.187-201
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• 2005

최근 전통적인 액체상 공정을 대체하는 기술로서 고체 담체와 단백질 사이의 '생물인식' 기능을 이용하는 새로운 생물공정기술이 개발되고 있다. 통상 고체 담체로는 표면에 특정한 기능기가 노출되어 있는 크로마토그래피용 담체를 사용한다. 단백질의 반응이나 상호작용이 단백질이 담체 표면에 부착되어 있는 상태에서 일어나기 때문에 이 '고체상 기술'은 액체상 기술에 비해 뚜렷한 장점을 갖고 있다. 고체상 재접힘은 변성제에 의해 용해된 내포체 형태의 재조합 단백질을 이온교환수지 표면에 흡착시켜 시작한다. 변성제를 단백질 주위로부터 서서히 제거시키면서 고유의 3차 구조로 재접힘시킨다. 재접힘이 완료되면 염 구배와 같은 전통적인 방법에 의해 재접힘된 단백질을 정제된 상태로 용출시킨다. 이 개념은 '확장층 흡착 재접힘'에도 연장 적용된다. 세포파쇄액에 변성제를 첨가하여 용해한 내포체 단백질은 확장층 흡착 크로마토그래피용 Streamline 담체에 흡착되고 세포찌꺼기와 불순 단백질들은 확장층 사이로 빠져 칼럼 밖으로 제거된다. 흡착된 목적 단백질은 고체상 재접힘 방법에 의해 재접힘 된 후 용출된다. 수년간 연구 발전되어 온이 새로운 재접힘 기술은 정제수율 향상, 공정 단계 감축, 공정 시간 및 부피 감소에 따라 생물의약공정의 경제성을 크게 향상시킬 수 있는 것으로 증명되고 있다. 본 논문에서는 실험실에서 수행한 여러 생물의약용 단백질들을 대상으로 한 연구 실험 자료를 바탕으로 고체상 재접힘 기술의 적용 사례를 서술하였다.

• 약학회지
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• 제39권4호
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• pp.395-400
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• 1995

The sorption and desorption properties of four adsorbents were evaluated for the trace enrichment of clobazam from biological samples. Graphitized carbon black(GCB) gaved the highest dynamic adsorption coefficient. Among the six organic solvents examined, acetone gave the highest desorption coefficient for the clobazam adsorbed on GCB. Using the GCB column, the optimum elution volume of the eluting solvent was evaluated from the on-line monitored breakthrough curve for clobazam. When GCB as the solid adsorbent and acetone as the eluting solvent were used for the solidphase extraction of clobazam from serum, the recoveries were higher than 83% with good reproducibility in the concentration range of 20-50 $\mu\textrm{g}$/ml.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.309-309
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• 2000

The main objective of this study is to understand the regeneration step of the PTSA(Pressure and thermal swing adsorption) process below the atmospheric pressure by rigorous dynamic simulation. This target process is to recover toluene using activated carbon as an adsorbent. To do this, the dynamic simulations for the regeneration step are performed at 360, 490, 590mmHg and at high temperature after the simulation of the adsorption step at latm and 298K. A mathematical model was developed to simulate the column dynamics of the adsorption systems. This model is based on non-equilibrium, non-isothermal and non-adiabatic conditions, and axial dispersion and heat conduction are also considered. Heat transfer resistances are considered in gas-solid, gas-column wall and column wall-outside air. The LDF(Linear Driving Force) approximation model describes the mass transfer rate between the gas and solid phase. This study shows that the recovery of toluene by PTSA is more preferable than that by general TSA.

• 약학회지
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• 제36권2호
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• pp.120-125
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• 1992

Ths sorption and desorption properties of four different solid adsorbents were evaluated for the trace enrichment of diphenylhydantoin from biological samples. Graphitized carbon black(GCB) gave the highest adsorption coefficient. And among the organic solvents examined, methanol gave the highest desorption coefficient. Using the GCB column, the optimum elution volume of the eluting solvent was evaluated from the breakthrough curve of diphenylhydantoin. The usefulness of GCB as the solid adsorbent was examined for the solid-phase extraction of diphenylhydantoin from serum in the concentration range of $20-50\;{\mu}g/ml$.

• 대한화학회지
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• 제52권4호
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• pp.362-368
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• 2008

• Carbon letters
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• 제24권
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• pp.10-17
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• 2017

With continuous development in the field of sample preparation technology, solid phase micro-extraction (SPME) has been widely used in analytical chemistry for high extraction efficiency and convenient operation. Different materials lead to different extraction results. Among existing materials, carbon-based materials are still attracting attention from scientists due to their excellent physical and chemical properties as well as their modifiable surfaces, which could enhance the adsorption effects of SPME fiber. This review introduces the preparation methods and applications of different kinds of carbon-based material coatings on fibers. In addition, directions for future research on carbon material composites are discussed.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권1호
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• pp.1-5
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• 2002

A fusion protein, consisting of a human epidermal growth factor (hEGF) as the recognition domain and human angiogenin as the toxin domain, can be used as a targeted therapeutic against breast cancer cells among others. The fusion protein was expressed as inclusion body in recombinant E. coli, and when the conventional, solution-phase refolding process was used the refolding yield was very low due to severe aggregation. It was probably because of the opposite electric charge at a neutral pH resulting from the vastly different pI values of each domain. The solid-phase refolding process that exploited the ionic interactions between ionic exchanger surface and the fusion protein was tried, but the adsorption yield was also very low, below $ 30\%$, regardless of the resins and pH conditions used. Therefore, to provide a higher ionic affinity toward the solid matrix, six lysine residues were tagged to the N-terminus of the hEGF domain. When heparin-Sepharose was used as the matrix, the adsorption capacity increased 2.5-3 times to about $88\%$. Besides the intrinsic affinity of angiogenin to heparin, the poly-lysine tag provided additional ionic affinity. And the subsequent refolding yield increased nearly 13-fold, from ca. $4.8\%$ in the conventional refolding of the untagged fusion protein to $63.6\%$. The process was highly reproducible. The refolded protein in the column eluate retained RNase bioactivity of angiogenin.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권5호
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• pp.20-28
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• 2021

Perfluorinated compounds(PFCs), an emerging environmental pollutant, are environmentally persistent and bioaccumulative organic compounds that possess a toxic impact on human health and ecosystems. PFCs are distributed widely in environment media including groundwater, surface water, soil and sediment. PFCs in contaminated solid can potentially leach into groundwater. Therefore, understanding PFCs partitioning between the aqueous phase and solid phase is important for the determination of their fate and transport in the environment. In this study, the sorption equilibrium batch and kinetic experiment of PFCs were carried out to estimated the sorption coefficient(K_d) and the fraction between aqueous-solid phase partition, respectively. Sorption branches of the PFDA(Perfluoro-n-decanoic acid), PFNA(Perfluoro-n-nonanoic acid), PFOA(Perfluoro-n-octanoic acid), PFOS(Perfluoro-1-octane sulfonic acid) and PFHxS(Perfluoro-1-hexane sulfonic acid) isotherms were nearly linear, and the estimated K_d was as follow: PFDA(1.50) > PFOS(1.49) > PFNA(0.81) > PFHxS(0.45) > PFOA(0.39). The sorption kinetics of PFDA, PFNA, PFOA, PFOS and PFHxS onto soil were described by a biexponential adsorption model, suggesting that a fast transport into the surface layer of soil, followed by two-step diffusion transport into the internal water and/or organic matter of soil. Shorter times(<20hr) were required to achieve equilibrium and fraction for adsorption on solid(F₁, F₂) increased with perfluorinated carbon chain length and sulfonate compounds in this study. Overall, our results suggested that not only the perfluorocarbon chain length, but also the terminal functional groups are important contributors to electrostatic and hydrophobic interactions between PFCs and soils, and organic matter in soils significantly affects adsorption maximum capacity than kinetic rate.

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.45-50
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• 2014

A fully packed capillary electrochromatographic (CEC) microchip with an on-column micro-solid phase extraction (SPE) bed for the preconcentration and separation of organic analytes was prepared. A linear microchannel with monodisperse colloidal silica packing was formed on a cyclic olefinic copolymer microchip with two reservoirs on both ends. Silver-cemented silica packing frit structure was formed at the entrance of the microchannel by electroless plating treatment as a base layer. A gold coating was formed on it by reducing $Au^{3+}$ to gold with hydroxylamine. Finally micro-SPE bed was formed by self-assembly adsorption of 1-dodecanethiol on it. Micro-SPE beds were about 100-150 ${\mu}m$ long. Approximately $10^3$ fold sensitivity enhancements for Sulforhodamine B, and Fluorescein in nM concentration levels were possible with 80 s preconcentration. Basic extraction characteristics were studied.

• Archives of Pharmacal Research
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• 제17권3호
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• pp.175-181
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• 1994

The solid-phase extraction (SPF) with subsequent tert-butyldimethylsilyl (TBDMS) derivatization was investigated for the rapid profiling and screening of various carboxylated non-steroidal antiinflammatory drugs (NSAIDs) simultaneously in biological fluid samples. Compared to the conventional SPF in adsorption mode using Chromosorb 102, Chromosorb 107, Carbopak B and Thermosorb, the SPF in partition mode using Chromosorb P as the adsorbent, and ethyl acetate/methylene chloride as the eluting solvents provided hightest overall recovenies of the NSAIDs from aqueous solutions with good precision. The solid-phase extracted NASIDs were silylated with N-methyl-N-(tert-butyldimethylsily)trifuoroacetamide to TBDMS derivatives and directly analyzed by capillary gas chromatography and gs chromatography-mass spectrometry. The usefulness of the present method was examined for the profilling and screening of saliva, serum and urine samples for various NSAIDs simultaneously.