Microalgae amino acid extraction and analysis at nanomolar level using electroporation and capillary electrophoresis with laser‐induced fluorescence detection

Abstract

Amino acids play a key role in food analysis, clinical diagnostics, and biochemical research. Capillary electrophoresis with laser-induced fluorescence detection was used for the analysis of several amino acids. Amino acid labeling with fluorescein isothiocyanate was conducted using microwave-assisted derivatization at 80°C (680 W) during only 150 s. Good electrophoretic resolution was obtained using a background electrolyte composed of sodium tetraborate buffer (100 mM; pH 9.4) and β-cyclodextrin (10 mM), and the limits of quantification were 3-30 nM. The developed capillary electrophoresis with laser-induced fluorescence method was used to analyze amino acids in Dunaliella salina green algae grown under different conditions. A simple extraction technique based on electroporation of the cell membrane was introduced. A home-made apparatus allowed the application of direct and alternating voltages across the electrochemical compartment containing a suspension of microalgae in distilled water at 2.5 g/L. A direct voltage of 12 V applied for 4 min gave the optimum extraction yield. Results were comparable to those obtained with accelerated-solvent extraction. The efficiency of electroporation in destroying microalgae membranes was shown by examining the algae surface morphology using scanning electron microscopy. Stress conditions were found to induce the production of amino acids in Dunaliella salina cells.

Study of the effect of culture mediums on the amino acid metabolites for Corynebacterium glutamicum using high‐speed micellar electrokinetic chromatography

“…Therefore, to develop a quick derivatization method for AAs was necessary for the determination of these compounds. Microwave‐assisted derivatization could significantly reduce the derivatization time for AAs . Microwave power was a crucial factor that affected the derivatization.…”

“…As a widely used derivatization reagent, FITC can easily reacts with primary amine group and generates strong fluorescence signals compatible with the LIF detector (excitation 473 nm and emission 525 nm). But the shortcoming for FITC is the long derivatization time (>16 h) for incubation at room temperature . Although HSCE greatly shortens the separation time (<5 min), the derivatization for AAs can greatly prolong the whole analysis time.…”

Recent advances in the bioanalytical methods of polyethylene glycols and PEGylated pharmaceuticals

“…Fluorescence labeling is a crucial tool to detect the fluorescence emitted from labeled molecules in analysis samples as a qualitative index [112–116]. Most fluorophores are small organic compounds with the conjugated unsaturated bond system.…”

Separation and determination of peptide metabolite of Bacillus licheniformis in a microbial fuel cell by high-speed capillary micellar electrokinetic chromatography

“…Compared with traditional separation means like ion exchange chromatography and HPLC , CE, including high‐speed capillary electrophoresis (HSCE), has significant advantages, like high efficiency, less sample consumption and short analysis time. These advantages make CE very suitable for analyzing these compounds including AAs and peptides . Fang et al.…”

“…Compared with traditional separation means like ion exchange chromatography [12] and HPLC [13,14], CE, including high-speed capillary electrophoresis (HSCE), has significant advantages, like high efficiency, less sample consumption and short analysis time. These advantages make CE very suitable for analyzing these compounds including AAs and peptides [15][16][17][18][19][20][21][22][23][24][25][26][27]. Fang et al proposed a picoliterscale spontaneous sample injection technique for HSCE and obtained ultra-high column efficiency in a very short separation time [28,29].…”