Takeyuki Akita
YOU?
Author Swipe
View article: Sensitive Fluorescence Determination of Tryptophan Enantiomers Derivatized with 4-Fluoro-7-nitro-2,1,3-benzoxadiazole Using a Photo-Reactor
Sensitive Fluorescence Determination of Tryptophan Enantiomers Derivatized with 4-Fluoro-7-nitro-2,1,3-benzoxadiazole Using a Photo-Reactor Open
View article: Three-dimensional high-performance liquid chromatographic determination of serine, threonine and allothreonine enantiomers in mouse tissues and physiological fluids
Three-dimensional high-performance liquid chromatographic determination of serine, threonine and allothreonine enantiomers in mouse tissues and physiological fluids Open
View article: Analysis of Alanine and Serine Enantiomers in Vinegars Using a Meter-long High-resolution Enantioselective Column
Analysis of Alanine and Serine Enantiomers in Vinegars Using a Meter-long High-resolution Enantioselective Column Open
View article: Enantioselective three-dimensional high-performance liquid chromatographic determination of amino acids in the Hayabusa2 returned samples from the asteroid Ryugu
Enantioselective three-dimensional high-performance liquid chromatographic determination of amino acids in the Hayabusa2 returned samples from the asteroid Ryugu Open
The chirality of amino acids in extraterrestrial materials may provide an insight into the origin of the essential l-enantiopure amino acids in the terrestrial biosphere. In 2020, the Hayabusa2 mission succeeded in bringing back surface ma…
View article: Enantioselective Analysis of Lactate, Hydroxybutyrates and Malate in Human Physiological Fluids Using a Three-Dimensional HPLC System
Enantioselective Analysis of Lactate, Hydroxybutyrates and Malate in Human Physiological Fluids Using a Three-Dimensional HPLC System Open
For the highly-selective analysis of lactic acid (LA), 2-hydroxybutyric acid (2HB), 3-hydroxybutyric acid (3HB) and malic acid (MA) enantiomers in human physiological fluids, a three-dimensional (3D) HPLC method following the fluorescence …
View article: Development of an enantioselective three-dimensional HPLC system for the determination of alanine, valine, isoleucine, allo-isoleucine and leucine in human plasma and urine
Development of an enantioselective three-dimensional HPLC system for the determination of alanine, valine, isoleucine, allo-isoleucine and leucine in human plasma and urine Open
A three-dimensional (3D) HPLC system was designed/developed for the discriminative determination of aliphatic chiral amino acids, namely, alanine (Ala), valine (Val), isoleucine (Ile), allo-Ile (aIle) and leucine (Leu), in human physiologi…
View article: Design of Novel Mixed-Mode Columns for Analysis of Amino Acids Derivatized with 4-Fluoro-7-nitro-2,1,3-benzoxadiazole and the Evaluation of Retention Properties
Design of Novel Mixed-Mode Columns for Analysis of Amino Acids Derivatized with 4-Fluoro-7-nitro-2,1,3-benzoxadiazole and the Evaluation of Retention Properties Open
Three-dimensional (3D) HPLC methods are useful tools for the selective analysis of biomolecules in complicated real-world matrices, however, the columns applicable for the second dimension are still limited. In the present study, two types…
View article: Development of a three-dimensional HPLC system for acidic amino acid enantiomers and determination of their amounts in mice lacking D-aspartic acid oxidase activity
Development of a three-dimensional HPLC system for acidic amino acid enantiomers and determination of their amounts in mice lacking D-aspartic acid oxidase activity Open
A highly-selective three-dimensional (3D) HPLC system has been designed/developed for the determination of acidic amino acid enantiomers, i.e., aspartic acid (Asp) and glutamic acid (Glu). The 3D-HPLC system consisted of a reversed-phase c…
View article: Chiral Amino Acid Analysis in the Plasma of B6DAO<sup>-/-</sup> Mice Lacking D-Amino Acid Oxidase Activity
Chiral Amino Acid Analysis in the Plasma of B6DAO<sup>-/-</sup> Mice Lacking D-Amino Acid Oxidase Activity Open
A B6DAO-/- mouse strain lacking D-amino acid oxidase (DAO) activity with the genetic background of C57BL strain, frequently used to produce disease model mice in the current medical/life science areas, was newly developed. In the plasma of…
View article: Two-Dimensional Chiral HPLC Analysis of Lactate, Hydroxybutyrates and Malate in Human Plasma
Two-Dimensional Chiral HPLC Analysis of Lactate, Hydroxybutyrates and Malate in Human Plasma Open
For the simultaneous determination of lactate (LA), 2-hydroxybutyrate (2HB), 3-hydroxybutyrate (3HB) and malate (MA) enantiomers, a new separation technique in a two-dimensional high-performance liquid chromatography (2D-HPLC) system follo…
View article: Enantioselective Determination of Hydroxy Amino Acids in Japanese Traditional Amber Rice Vinegars
Enantioselective Determination of Hydroxy Amino Acids in Japanese Traditional Amber Rice Vinegars Open
A fully-automated two-dimensional (2D) HPLC system for the determination of serine (Ser), threonine (Thr) and allo-threonine (aThr) enantiomers was developed. The system was validated and applied to the determination of the target hydroxy …
View article: Two-Dimensional High-Performance Liquid Chromatographic Determination of Chiral Amino Acids in Food Samples and Human Physiological Fluids Using Fluorescence Derivatization with 4-(<i>N</i>,<i>N</i>-Dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole
Two-Dimensional High-Performance Liquid Chromatographic Determination of Chiral Amino Acids in Food Samples and Human Physiological Fluids Using Fluorescence Derivatization with 4-(<i>N</i>,<i>N</i>-Dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole Open
A two-dimensional high-performance liquid chromatographic (2D-HPLC) system using the pre-column derivatization with 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F) has been developed for the determination of alanine (Al…
View article: Chiral Analysis of Lactate in Various Food Samples Including Japanese Traditional Amber Rice Vinegar and the Developmental Changes During Fermentation Processes
Chiral Analysis of Lactate in Various Food Samples Including Japanese Traditional Amber Rice Vinegar and the Developmental Changes During Fermentation Processes Open
Enantioselective analysis of lactate (LA) in various fermented food/beverage samples including the Japanese traditional amber rice vinegars was performed using a newly designed three-dimensional high-performance liquid chromatographic (3D-…
View article: Acridinium Ester Chemiluminescence: Methyl Substitution on the Acridine Moiety
Acridinium Ester Chemiluminescence: Methyl Substitution on the Acridine Moiety Open
Methyl groups were introduced on the acridine moiety in chemiluminescent acridinium esters that have electron-withdrawing groups (trifluoromethyl, cyano, nitro, ethoxycarbonyl) at the 4-position on the phenyl ester. The introduction of met…
View article: High-Performance Liquid Chromatographic Determination of Chiral Amino Acids Using Pre-Column Derivatization with <i>o</i>-Phthalaldehyde and <i>N</i>-<i>tert</i>-Butyloxycarbonyl-D-cysteine and Application to Vinegar Samples
High-Performance Liquid Chromatographic Determination of Chiral Amino Acids Using Pre-Column Derivatization with <i>o</i>-Phthalaldehyde and <i>N</i>-<i>tert</i>-Butyloxycarbonyl-D-cysteine and Application to Vinegar Samples Open
A reversed-phase high-performance liquid chromatographic (HPLC) method using pre-column derivatization with o-phthalaldehyde (OPA) plus N-tert-butyloxycarbonyl-D-cysteine (Boc-D-Cys) has been developed for the determination of aspartic aci…
View article: Determination of Chiral Amino Acids in Various Fermented Products Using a Two-Dimensional HPLC-MS/MS System
Determination of Chiral Amino Acids in Various Fermented Products Using a Two-Dimensional HPLC-MS/MS System Open
Chiral amino acids in fermented products including Japanese traditional black vinegar, a processed cheese and nam pla were determined using an on-line two-dimensional (2D) HPLC-MS/MS system. As the target amino acids, Ala, Asp, Glu, Leu, P…
View article: Development of a Three-Dimensional HPLC System for the Simultaneous Determination of Lactate and 3-Hydroxybutyrate Enantiomers in Mammalian Urine
Development of a Three-Dimensional HPLC System for the Simultaneous Determination of Lactate and 3-Hydroxybutyrate Enantiomers in Mammalian Urine Open
For the highly chemoselective separations of lactate (LA) and 3-hydroxybutyrate (3HB) enantiomers in mammalian urine, an online three-dimensional HPLC system (3D-HPLC) composed of reversed-phase (KSAARP, 1.0 mm i.d. x 250 mm), mixed-mode (…
View article: Determination of Trace Amounts of Chiral Amino Acids in Complicated Biological Samples Using Two-Dimensional High-Performance Liquid Chromatography with an Innovative “Shape-Fitting” Peak Identification/Quantification Method
Determination of Trace Amounts of Chiral Amino Acids in Complicated Biological Samples Using Two-Dimensional High-Performance Liquid Chromatography with an Innovative “Shape-Fitting” Peak Identification/Quantification Method Open
A new peak identification/quantification method, i.e., "shape-fitting" method, has been devised and applied to the determination of chiral amino acids in human plasma and urine. The shape fitting method enables the determination of target …
View article: Development of a Highly-Sensitive Two-Dimensional HPLC System with Narrowbore Reversed-Phase and Microbore Enantioselective Columns and Application to the Chiral Amino Acid Analysis of the Mammalian Brain
Development of a Highly-Sensitive Two-Dimensional HPLC System with Narrowbore Reversed-Phase and Microbore Enantioselective Columns and Application to the Chiral Amino Acid Analysis of the Mammalian Brain Open
A highly-sensitive two-dimensional high-performance liquid chromatographic (2D-HPLC) system with narrowbore reversed-phase and microbore enantioselective columns has been developed for the determination of alanine (Ala) and serine (Ser) en…
View article: Multi-Dimensional HPLC Analysis of Serine Containing Chiral Dipeptides in Japanese Traditional Amber Rice Vinegar
Multi-Dimensional HPLC Analysis of Serine Containing Chiral Dipeptides in Japanese Traditional Amber Rice Vinegar Open
Several D-amino acids have been identified in higher animals including humans, and are now increasingly recognized as biologically active substances and/or biomarkers. Therefore, the presence of related compounds, such as dipeptides, conta…