Homocyclic o‐dicarboxaldehydes: Derivatization reagents for sensitive analysis of amino acids and related compounds by capillary and microchip electrophoresis

Abstract

Amino acids are essential compounds for living organisms, and their determination in biological fluids is crucial for the clinical analysis and diagnosis of many diseases. However, the detection of most amino acids is hindered by the lack of a strong chromophore/fluorophore or electrochemically active group in their chemical structures. The highly sensitive determination of amino acids often requires derivatization. Capillary electrophoresis is a separation technique with excellent characteristics for the analysis of amino acids in biological fluids. Moreover, it offers the possibility of precapillary, on‐capillary, or postcapillary derivatization. Each derivatization approach has specific demands in terms of the chemistry involved in the derivatization, which is discussed in this review. The family of homocyclic o‐dicarboxaldehyde compounds, namely o‐phthalaldehyde, naphthalene‐2,3‐dicarboxaldehyde, and anthracene‐2,3‐dicarboxaldehyde, are powerful derivatization reagents for the determination of amino acids and related compounds. In the presence of suitable nucleophiles they react with the primary amino group to form both fluorescent and electroactive derivatives. Moreover, the reaction rate enables all of the derivatization approaches mentioned above. This review focuses on articles that deal with using these reagents for the derivatization of amino acids and related compounds for ultraviolet‐visible spectrometry, fluorescence, or electrochemical detection. Applications in capillary and microchip electrophoresis are summarized and discussed.

Recent developments in capillary and microchip electroseparations of peptides (2019–mid 2021)

“…Application of homocyclic o ‐dicarboxal aldehydes, o ‐phthalaldehyde, naphthalene‐2,3‐dicarboxaldehyde, and anthracene‐2,3‐dicarboxyaldehyde, for derivatization of AAs and related compounds, including peptides in their CE analysis with UV‐vis, fluorescence and electrochemical detection was reviewed by Cela and Glatz [87].…”

Capillary and microchip electrophoresis method development for amino acid monitoring during biopharmaceutical cultivation

“…NDA can be used to derivatize primary amines, that is, all standard AAs except proline (Pro), in the presence of the cyanide anion. [ 21 ] NDA itself is not fluorescent but absorbs UV. Thus, while optimizing the separation, derivatizations were performed with a molar excess of AAs in relation to NDA to avoid interfering peaks of excess NDA and its degradation products.…”

Recent advances in microchip electrophoresis for analysis of pathogenic bacteria and viruses

“…Such applications involve forensic genotyping [66, 67], analysis of illicit drugs [68], separation of explosive residues [69], and forensic screening of adulterations in beverages [70–72]. It was also applied to the analysis of small molecules such as pharmaceutical compounds [73–78], amino acids [75, 79, 80], environmental contaminants [81–83], and specific biomarkers [84–87]. Its use in the analysis of microbial contaminations of water, air, and foodstuffs has witnessed a great interest in the last decade [88–90].…”