基礎講座 電気泳動(Electrophoresis)

Hydrophilic interaction liquid chromatography (HILIC) provides an alternative approach to effectively separate small polar compounds on polar stationary phases. The purpose of this work was to review the options for the characterization of HILIC stationary phases and their applications for separations of polar compounds in complex matrices. The characteristics of the hydrophilic stationary phase may affect and in some cases limit the choices of mobile phase composition, ion strength or buffer pH value available, since mechanisms other than hydrophilic partitioning could potentially occur. Enhancing our understanding of retention behavior in HILIC increases the scope of possible applications of liquid chromatography. One interesting option may also be to use HILIC in orthogonal and/or two-dimensional separations. Bioapplications of HILIC systems are also presented.

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Hydrophilic interaction liquid chromatography (HILIC)—a powerful separation technique

The key objectives of medicinal chemistry are to efficiently design and synthesize bioactive compounds that have the potential to become safe and efficacious drugs. Most medicinal chemistry programmes rely on screening compound collections populated by a range of molecules derived from a set of known and robust chemistry reactions. Analysis of the role of synthetic organic chemistry in subsequent hit and lead optimization efforts suggests that only a few reactions dominate. Thus, the uptake of new synthetic methodologies in drug discovery is limited. Starting from the known limitations of reaction parameters, synthesis design tools, synthetic strategies and innovative chemistries, here we highlight opportunities for the expansion of the medicinal chemists' synthetic toolbox. More intense crosstalk between synthetic and medicinal chemists in industry and academia should enable enhanced impact of new methodologies in future drug discovery.

Expanding the medicinal chemistry synthetic toolbox

Metabolites are the small biological molecules involved in energy conversion and biosynthesis. Studying metabolism is inherently challenging due to metabolites' reactivity, structural diversity, and broad concentration range. Herein, we review the common pitfalls encountered in metabolomics and provide concrete guidelines for obtaining accurate metabolite measurements, focusing on water-soluble primary metabolites. We show how seemingly straightforward sample preparation methods can introduce systematic errors (e.g., owing to interconversion among metabolites) and how proper selection of quenching solvent (e.g., acidic acetonitrile:methanol:water) can mitigate such problems. We discuss the specific strengths, pitfalls, and best practices for each common analytical platform: liquid chromatography-mass spectrometry (LC-MS), gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR), and enzyme assays. Together this information provides a pragmatic knowledge base for carrying out biologically informative metabolite measurements.

Metabolite Measurement: Pitfalls to Avoid and Practices to Follow

https://espace.library.uq.edu.au/view/UQ:371219/UQ371219_OA.pdf

Spoilt for choice: A critical review on the chemical and biological assessment of current wastewater treatment technologies.

Hydrophilic interaction liquid chromatography columns classification by effect of solvation and chemometric methods.

The goal of the study was to investigate separation mechanism of selected “essential” amino acids (leucine, isoleucine, threonine, tryptophan, proline, and glycine) and vitamin B6 in hydrophilic interaction liquid chromatography (HILIC) with the evaporative light scattering detection. Chromatographic measurements were made on three different HILIC columns: amide-silica (TSK-gel Amide-80), amino-silica (TSK-gel NH2-100), and cross-linked diol (Luna HILIC). The retention behaviour of the analytes was investigated as a function of different binary hydro-organic mobile phases containing 10–90 % (v/v) acetonitrile. The compounds studied were separated under isocratic and gradient conditions. The best results of tested biologically active compounds separation were obtained on the TSK-gel NH2-100 column. TSK-gel NH2 column showed mixed HILIC–ion-exchange mechanism, the highest separation efficiency and better selectivity and resolution for tested analytes than the other studied column, especially at concentration of water in mobile phase lower than 30 % (v/v). Special attention was dedicated to the study of interactions among the stationary phase, mobile phase and the analytes.

/pdf/retention-mechanism-studies-of-selected-amino-acids-and-1w7oaruu1x.pdf

Retention Mechanism Studies of Selected Amino Acids and Vitamin B6 on HILIC Columns with Evaporative Light Scattering Detection

The goal of the study was to investigate the retention mechanism of selected fungicides in hydrophilic interaction liquid chromatography (HILIC) and per aqueous liquid chromatography (PALC). Chromatographic measurements were made on four physicochemically diversified HILIC columns, which were evaluated for the analysis of nine biologically active compounds, such as strobilurins and triazoles. The effects of the operating conditions on separations were investigated, including the concentration of the organic solvent in the aqueous-organic (acetonitrile) mobile phase. The results were compared, and it was shown that two different retention mechanisms dominate in PALC at low acetonitrile concentrations and in HILIC at high acetonitrile concentrations.

Hydrophilic interaction liquid chromatography and per aqueous liquid chromatography in fungicides analysis.

The objectives of this study were to investigate the molecular mechanisms of retention of selected fungicides and to classify stationary phases used for RP-HPLC. Chromatographic measurements were made using eight physicochemically diverse HPLC columns which were evaluated for analysis of nine biologically active compounds (strobilurins and triazoles). QSRRs were derived for the logarithms of the retention factors normalized to a hypothetical zero percent organic modifier in the mobile phase, log k
 W. Structural descriptors of the pesticides were used to describe their chromatographic retention behaviour under the given LC conditions. The next step was the correlation between retention data, log k
 W, and the structural descriptors of the analytes from molecular modelling.

Sylwia Noga

Papers

Hydrophilic interaction liquid chromatography (HILIC)—a powerful separation technique

Hydrophilic interaction liquid chromatography columns classification by effect of solvation and chemometric methods.

Retention Mechanism Studies of Selected Amino Acids and Vitamin B6 on HILIC Columns with Evaporative Light Scattering Detection

Hydrophilic interaction liquid chromatography and per aqueous liquid chromatography in fungicides analysis.

Effect of Functionalized Stationary Phases on the Mechanism of Retention of Fungicides in RP-LC Elution