• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.220.1-220.1
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• 2003

A sensitive and selective liquid chromatographic method for the determination of carvedilol in human plasma was developed and validated. Analytes were separated on a XTerra C18 column with acetonitrile-methanol-30 mM KH$_2$PO$_4$ (pH 2.5) (20 : 20 : 60, v/v/v), as mobile phase. One mL plasma were pipetted into glass tubes and spiked with 0.05 mL of internal standard solution. After adding 7 mL of diethyl ether, the plasma sample was then shacked for 15 min. A centrifuged upper layer was back-extracted with 150 uL of 0.05 M sulfuric acid. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.278.2-278.2
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• 2003

A column-switching semi-micro HPLC method with fluorescence detection was developed for the direct analysis of rebamipide in human plasma. Plasma was filtered through a 0.45 $\mu\textrm{m}$ membrane filter and 5 ${\mu}\ell$ of the filtrate was directly injected onto the pre-column. After elution of the plasma proteins to waste, the retained rebamipide and internal standard(ofloxacin) were transferred to a C18 semi-microcolumn (5$\mu\textrm{m}$, 150 ${\times}$2.0mm) where they were separated using acetonitrile-1.4％ acetic acid (40:60, v/v) as mobile phase. (omitted)

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.276.1-276.1
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• 2003

This study describes a simple and sensitive semi-micro HPLC method with UV detection and direct deproteinization. The plasma protein was precipitated using perchloric acid (60％) and the supernatant was directly injected onto the semi-micro HPLC system. The separation was achieved on a C18 (25 mm ${\times}$ 2.0 mm I.D) analytical column with a mobile phase of sodium acetate buffer (pH 3.5, 50 mmol) - acetonitrile (60:40, V/V). (omitted)

• 한국미생물·생명공학회지
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• 제51권1호
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• pp.37-42
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• 2023

Neutral and non-essential amino acid, glutamine (Gln), plays an essential role in supplying nitrogen to all the amino acids and nucleotides in the mammalian body. Gln is also the most important carbon source that provides intermediates for gluconeogenesis and fatty acid synthesis and supplements the tricarboxylic acid cycle in fast-growing cancer cells. Among the known 14 Gln transporter genes, soluted carrier family 1 member 5 (SLC1A5) has been reported to be closely associated with cancer cell growth. Three variants (v1, v2, and v3) have been derived from SLC1A5. Here, we established a heterologous gene expression system for the active form of human SLC1A5 variant-2 (hSLC1A5v2) in Escherichia coli. v2 is the smallest variant that has not yet been studied. Four expression systems were investigated: pBAD, pCold, pET, and pQE. We also addressed the problem of codon usage bias. Although pCold and pET overexpressed hSLC1A5v2 in E. coli, they were functionally inactive. hSLC1A5v2 using the pBAD system was able to catalyze the successful transport of Gln, even if it was not highly expressed. Initial activity of hSLC1A5v2 for [¹⁴C] Gln uptake in E. coli reached up to 6.73 μmole·min^-1·gDW^-1 when the cell was induced with 80 mM L-arabinose. In this study, we demonstrated a heterologous expression system for the human membrane protein, SLC1A5, in E. coli. Our results can be used for the functional comparison of SLC1A5 variants (v1, v2, and v3) in future studies, to facilitae the developement of SLC1A5 inhibitors as effective anticancer drugs.