• Mass Spectrometry Letters
• /
• v.12 no.3
• /
• pp.85-92
• /
• 2021

The therapeutic antibody drug market has experienced explosive growth as mAbs become the main therapeutic modality for a variety of diseases. Characterization of glycosylation that directly affects the efficacy and safety of therapeutic monoclonal antibodies (mAbs) is critical for therapeutics development, bioprocess system optimization, lot release, and comparability evaluation. The LC/MS approach has been widely used to structurally characterize mAbs, and recently attempts have been made to obtain comprehensive information on the primary structure and post-translational modifications (PTMs) of mAbs through intact protein analysis. In this study, we performed state-of-the-art LC/MS based intact protein analysis to readily identify and characterize glycoforms of various mAbs. Different glycoforms of mAbs produced in different expression cell lines including CHO, SP2/0 and HEK cells were monitored and compared. In addition, the comparability of protein molecular weight, glycoform pattern, and relative abundances of glycoforms between the commercialized trastuzumab biosimilar and the original product was determined in detail using the given platform. Intact mAb analysis allowed us to gain insight into the overall mAb structure, including the complexity and diversity of glycosylation. Furthermore, our analytical platform with high reproducibility is expected to be widely used for biopharmaceutical characterization required at all stages of drug development and manufacturing.

• 한국초전도학회:학술대회논문집
• /
• 2009.07a
• /
• pp.56-56
• /
• 2009

• Proceedings of the Korean Society of Plant Biotechnology Conference
• /
• 2004.10a
• /
• pp.118-118
• /
• 2004

• Mass Spectrometry Letters
• /
• v.7 no.1
• /
• pp.16-20
• /
• 2016

Characterization of intact protein structures in the gas phase using electrospray ionization combined with ion mobility mass spectrometry has become an important tool of research. However, the biophysical properties that govern the structures of protein ions in the gas phase remain to be understood. Here, we investigated the impact of host-guest complexation of ubiquitin (Ubq) with macrocyclic host molecules, cucurbit[n]urils (CB[n]s, n = 6, 7), on its structure in the gas phase. We found that CB[n] complexation induces the formation of compact Ubq ions. Both CB[6] and CB[7] exhibited similar effects despite differences in their binding properties in solution. In addition, CB[n] attachment prevented Ubq from unfolding by collisional activation. Based on the experimental results, we suggest that CB[n]s prevent unfolding of Ubq during transfer to the gas phase to promote the formation of compact protein ions. Furthermore, interaction with positively charged residues per se is suggested to be the most important factor for the host-guest complexation effect.

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09b
• /
• pp.1116-1117
• /
• 2006

Lanthanide tantalite $LnTaO_4$ (Ln= La, Nd, Sm, Dy, Er and Tm) was synthesized by a solid state reaction between mixed powders of $Ln_2O_3$ and $Ta_2O_5$. The single-phase $LnTaO_4$ was prepared by sintering at temperatures of 1423-1673 K in air. The SEM observation showed that the particles were provided with the growth steps and the depeloped facets. The photocatalytic activity for water splitting of $LnTaO_4$ prepared was measured under UV light irradiation. The activity obtained was higher than that previously reported. These results suggested the crystallinity of $LnTaO_4$ photocatalysts correlates closely with the efficiency of water splitting.

• Food Science of Animal Resources
• /
• v.29 no.2
• /
• pp.157-163
• /
• 2009

This study was conducted for the isolation, purification, and characterization of a protease from Korean pear, to see its proteolytic activity on chicken actomyosin and to find the optimum pH and temperature of activity on chicken actomyosin. The protease was isolated from crude extract of Korean pear by ammonium sulfate precipitation. Further purification was done by DEAE-Sepharose ion-exchange chromatography, Mono-Q and Mini-Q column chromatography. The purified enzyme gave a single protein band on SDS polyacrylamide gel electrophoresis and the molecular weight was found to be 38 kDa. The specific activity of purified enzyme was 34,907 unit/mg with 25 fold purification and the yield was 2%. The purified enzyme incubated with chicken actomyosin showed high activity. The optimum pH and temperature for enzyme activity on chicken actomyosin were 6.5 and $70^{\circ}C$, respectively. A protease was purified from Korean pear for the first time and characterized. It was found to be promising for meat tenderization.

• Laser Solutions
• /
• v.17 no.4
• /
• pp.14-19
• /
• 2014

Laser beam was applied on the boundary of the polyurethane and biodegradable polyacetate polymers. The distributed laser passed through the polyurethane layer and heated the polyacetate layer, then the soften acetate was squeezed thorough the 1mm square slots of polyurethane for the mechanical joining. The surface roughness ranging between $0.28{\mu}m$ and $3.06{\mu}m$ had almost no effect on joining strength, but the optical properties of HD (High Definition) and UHD (Ultra High Definition) mode affected laser beam transmittance. The optimum laser power was found to be between 8watt and 10watt with 500mm/min of scanning speed. The joining boundary was characterized by optical and SEM analysis. Based on the experiment and characterization results, the laser energy was effective for the polymer joining and efficiency of joining.

• Journal of the Korean institute of surface engineering
• /
• v.37 no.3
• /
• pp.152-157
• /
• 2004

Ti-Al-N ($Ti_{75}$ $Al_{25}$ N) and Ti-Al-Si-N ($Ti_{69}$ $Al_{23}$ $Si_{8}$N) coatings synthesized by a DC magnetron sputtering technique were studied comparatively with respect to phase characterization and high-temperature oxidation behavior. $Ti_{69}$ $Al_{23}$ $Si_{ 8}$N coating had a nanocomposite microstructure consisting of nanosized(Ti,Al,Si)N crystallites and amorphous $Si_3$$N_4$, with smooth surface morphology. Ti-Al-N coating of which surface $Al_2$$O_3$ layer formed during oxidation suppressed further oxidation. It was sufficiently stable against oxidation up to about $700^{\circ}C$. Ti-Al-Si-N coating showed better oxidation resistance because both surface Ab03 and near-surface $SiO_2$ layers suppressed further oxidation. XRD, GDOES, XPS, and scratch tests were performed.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2007.08a
• /
• pp.439-442
• /
• 2007

Novel blue materials based on anthracene derivatives were synthesized by Grignard reaction, the Suziki coupling reaction, etc. They showed excellent thermal stability and emitted bright blue light, which will been used for OLED and expected to obtain high efficiency and good color purity.

• Journal of Practical Engineering Education
• /
• v.14 no.1
• /
• pp.165-177
• /
• 2022

The purpose of this study is to present the direction of employment guidance for long-term service through the analysis of the cause of employment of employed students who graduated from specialized high school. In particular, the purpose is to present student guidance plans for long-term service by analyzing personal reasons for students graduating from commercial high schools and policy factors for individual, school, company, and government service after employment. To this end, a survey was conducted for graduates of commercial high schools nationwide, and the validity, reliability, and causality of the survey data were analyzed by applying Exploratory Factor Analysis, Cronbach's Alpha, and decision tree analysis techniques. We found that personal goal setting for employment is an important factor for working for more than 1 year, personal relationships at work and personal characteristics are important factors for working for more than 3 years. In addition, we found that the reason for getting a job is that personal reasons and school recommendations are great, special lectures on employment, camps, and 'advice from seniors and teachers' programs are helpful in finding a job, and accounting and computer related subjects are helpful for long-term employment. Accordingly, in specialized high schools, it is required to prepare specific instructional measures for education such as setting personal goals and the formation of human relationships that are the basis of social life, and to actively operate the above subjects and programs to help with employment and longevity.