Practical examination of flow rate effects and influence of the stationary phase water layer on peak shape and retention in hydrophilic interaction liquid chromatography (2023)
Journal Article
McCalley, D. V. (2024). Practical examination of flow rate effects and influence of the stationary phase water layer on peak shape and retention in hydrophilic interaction liquid chromatography. Journal of Chromatography A, 1715, Article 464608. https://doi.org/10.1016/j.chroma.2023.464608

The effect of flow velocity on retention and peak shape of neutral, acidic and basic probe compounds was studied using seven different UHPLC hydrophilic interaction chromatography (HILIC) columns. Surprisingly on some columns, the retention factor k... Read More about Practical examination of flow rate effects and influence of the stationary phase water layer on peak shape and retention in hydrophilic interaction liquid chromatography.

Evaluation of additives on reversed-phase chromatography of monoclonal antibodies using a 1000 Å stationary phase (2019)
Journal Article
McCalley, D. V., & Guillarme, D. (2020). Evaluation of additives on reversed-phase chromatography of monoclonal antibodies using a 1000 Å stationary phase. Journal of Chromatography A, 1610, Article 460562. https://doi.org/10.1016/j.chroma.2019.460562

© 2019 Elsevier B.V. A wide pore (1000 Å) diphenyl stationary phase was evaluated for the analysis of monoclonal antibodies (mAbs), comparing a conventional mobile phase of acetonitrile-water containing overall 0.1% trifluoracetic acid (TFA) with a s... Read More about Evaluation of additives on reversed-phase chromatography of monoclonal antibodies using a 1000 Å stationary phase.

Hydrophilic interaction liquid chromatography: An update (2019)
Journal Article
McCalley, D. V. (2019). Hydrophilic interaction liquid chromatography: An update. Lc Gc Europe, 32(3), 114-125

This article is an update on the technique of hydrophilic interaction liquid chromatography (HILIC) and covers recent ideas on the mechanism of separation, and how it may be manipulated to suit the separation of particular sample types. The advantage... Read More about Hydrophilic interaction liquid chromatography: An update.

Retention characteristics of some antibiotic and anti-retroviral compounds in hydrophilic interaction chromatography using isocratic elution, and gradient elution with repeatable partial equilibration (2018)
Journal Article
Heaton, J. C., Smith, N. W., & McCalley, D. V. (2019). Retention characteristics of some antibiotic and anti-retroviral compounds in hydrophilic interaction chromatography using isocratic elution, and gradient elution with repeatable partial equilibration. Analytica Chimica Acta, 1045, 141-151. https://doi.org/10.1016/j.aca.2018.08.051

© 2018 Elsevier B.V. The separation of some zwitterionic, basic and neutral antibiotic and antiretroviral compounds was studied using hydrophilic interaction chromatography (HILIC) on bare silica, bonded amide and urea superficially porous phases. T... Read More about Retention characteristics of some antibiotic and anti-retroviral compounds in hydrophilic interaction chromatography using isocratic elution, and gradient elution with repeatable partial equilibration.

A study of column equilibration time in hydrophilic interaction chromatography (2018)
Journal Article
McCalley, D. V. (2018). A study of column equilibration time in hydrophilic interaction chromatography. Journal of Chromatography A, 1554, 61-70. https://doi.org/10.1016/j.chroma.2018.04.016

© 2018 Elsevier B.V. The time taken to achieve full column equilibration for isocratic analysis of acidic, basic, and neutral solutes in hydrophilic interaction liquid chromatography (HILIC) was compared using the mobile phase disturbance method, col... Read More about A study of column equilibration time in hydrophilic interaction chromatography.

A study of the analysis of acidic solutes by hydrophilic interaction chromatography (2017)
Journal Article
McCalley, D. V. (2018). A study of the analysis of acidic solutes by hydrophilic interaction chromatography. Journal of Chromatography A, 1534, 64-74. https://doi.org/10.1016/j.chroma.2017.12.045

© 2017 Elsevier B.V. The analysis of acidic solutes was compared on a cross-linked bonded amino phase and a neutral hybrid inorganic-organic amide phase, previously shown to give reasonable retention of acidic solutes. The amino column gave strong se... Read More about A study of the analysis of acidic solutes by hydrophilic interaction chromatography.

Understanding and manipulating the separation in hydrophilic interaction liquid chromatography (2017)
Journal Article
McCalley, D. V. (2017). Understanding and manipulating the separation in hydrophilic interaction liquid chromatography. Journal of Chromatography A, 1523, 49-71. https://doi.org/10.1016/j.chroma.2017.06.026

© 2017 Elsevier B.V. Hydrophilic interaction liquid chromatography (HILIC) has emerged as a valuable complimentary technique to reversed-phase (RP), being especially suited for the analysis of polar and ionised solutes, which are difficult to retain... Read More about Understanding and manipulating the separation in hydrophilic interaction liquid chromatography.

Effect of mobile phase additives on solute retention at low aqueous pH in hydrophilic interaction liquid chromatography (2016)
Journal Article
McCalley, D. V. (2017). Effect of mobile phase additives on solute retention at low aqueous pH in hydrophilic interaction liquid chromatography. Journal of Chromatography A, 1483, 71-79. https://doi.org/10.1016/j.chroma.2016.12.035

© 2016 Elsevier B.V. Trifluoracetic acid (TFA) added to the aqueous acetonitrile mobile phase induces some unexpected changes in the ionic component of retention in hydrophilic interaction separations when using Type B silica and amide-bonded silica... Read More about Effect of mobile phase additives on solute retention at low aqueous pH in hydrophilic interaction liquid chromatography.

Recent developments in support materials for use in high performance liquid chromatography (2016)
Journal Article
McCalley, D. V. (2016). Recent developments in support materials for use in high performance liquid chromatography

A number of advances have taken place in the last decade in the area of support materials for high performance liquid chromatography (HPLC). These developments have included the use of very small porous particles (< 2.0 micron diameter), new types of... Read More about Recent developments in support materials for use in high performance liquid chromatography.

Distinction of synthetic dl-α-tocopherol from natural vitamin E (d-α-tocopherol) by reversed-phase liquid chromatography. Enhanced selectivity of a polymeric C18 stationary phase at low temperature and/or at high pressure (2016)
Journal Article
Yui, Y., Miyazaki, S., Ma, Y., Ohira, M., Fiehn, O., Ikegami, T., …Tanaka, N. (2016). Distinction of synthetic dl-α-tocopherol from natural vitamin E (d-α-tocopherol) by reversed-phase liquid chromatography. Enhanced selectivity of a polymeric C18 stationary phase at low temperature and/or at high pressure. Journal of Chromatography A, 1450, 45-52. https://doi.org/10.1016/j.chroma.2016.04.076

© 2016 Elsevier B.V. Separation of diastereomers of DL-α-tocopherol was studied by reversed-phase liquid chromatography using three types of stationary phases, polymeric ODS, polymeric C30, and monomeric ODS. Polymeric ODS stationary phase (Inertsil... Read More about Distinction of synthetic dl-α-tocopherol from natural vitamin E (d-α-tocopherol) by reversed-phase liquid chromatography. Enhanced selectivity of a polymeric C18 stationary phase at low temperature and/or at high pressure.

Core-Shell, Ultrasmall Particles, Monoliths, and Other Support Materials in High-Performance Liquid Chromatography (2016)
Journal Article
Tanaka, N., & McCalley, D. V. (2016). Core-Shell, Ultrasmall Particles, Monoliths, and Other Support Materials in High-Performance Liquid Chromatography. Analytical Chemistry, 88(1), 279-298. https://doi.org/10.1021/acs.analchem.5b04093

A review of the developments that have taken place in the area of supports for high performance liquid chromatography in recent years.

Some factors that can lead to poor peak shape in hydrophilic interaction chromatography, and possibilities for their remediation (2016)
Journal Article
Heaton, J. C., Heaton, J., & McCalley, D. V. (2016). Some factors that can lead to poor peak shape in hydrophilic interaction chromatography, and possibilities for their remediation. Journal of Chromatography A, 1427, 37-44. https://doi.org/10.1016/j.chroma.2015.10.056

© 2015 Elsevier B.V. Some factors which present difficulties for obtaining good peak shape in hydrophilic interaction chromatography (HILIC) were studied. The effect of injection solvent composition and volume was systematically investigated using a... Read More about Some factors that can lead to poor peak shape in hydrophilic interaction chromatography, and possibilities for their remediation.

Performance of charged aerosol detection with hydrophilic interaction chromatography (2015)
Journal Article
Russell, J. J., Heaton, J. C., Underwood, T., Boughtflower, R., & McCalley, D. V. (2015). Performance of charged aerosol detection with hydrophilic interaction chromatography. Journal of Chromatography A, 1405, 72-84. https://doi.org/10.1016/j.chroma.2015.05.050

© 2015 The Authors. The performance of the charged aerosol detector (CAD) was investigated using a diverse set of 29 solutes, including acids, bases and neutrals, over a range of mobile phase compositions, particularly with regard to its suitability... Read More about Performance of charged aerosol detection with hydrophilic interaction chromatography.

Study of retention and peak shape in hydrophilic interaction chromatography over a wide pH range (2015)
Journal Article
McCalley, D. V. (2015). Study of retention and peak shape in hydrophilic interaction chromatography over a wide pH range. Journal of Chromatography A, 1411, 41-49. https://doi.org/10.1016/j.chroma.2015.07.092

© 2015 Elsevier B.V. Retention factor and column efficiency measurements were made for 14 test compounds comprising acids, bases and neutrals on two pairs of amide and bare silica HILIC columns, each pair obtained from a different manufacturer. The c... Read More about Study of retention and peak shape in hydrophilic interaction chromatography over a wide pH range.

The impact of pressure and frictional heating on retention, selectivity and efficiency in ultra-high-pressure liquid chromatography (2014)
Journal Article
McCalley, D. V. (2014). The impact of pressure and frictional heating on retention, selectivity and efficiency in ultra-high-pressure liquid chromatography. Trends in Analytical Chemistry, 63, 31-43. https://doi.org/10.1016/j.trac.2014.06.024

© 2014 Elsevier B.V. The effects of pressure and frictional heating deserve serious consideration in ultra-high-pressure liquid chromatography (UHPLC) separations, as the pressures used can be three times greater than those in conventional high-perfo... Read More about The impact of pressure and frictional heating on retention, selectivity and efficiency in ultra-high-pressure liquid chromatography.

Effect of pressure on the selectivity of polymeric C18 and C30 stationary phases in reversed-phase liquid chromatography. Increased separation of isomeric fatty acid methyl esters, triacylglycerols, and tocopherols at high pressure (2014)
Journal Article
Okusa, K., Iwasaki, Y., Kuroda, I., Miwa, S., Ohira, M., Nagai, T., …Tanaka, N. (2014). Effect of pressure on the selectivity of polymeric C18 and C30 stationary phases in reversed-phase liquid chromatography. Increased separation of isomeric fatty acid methyl esters, triacylglycerols, and tocopherols at high pressure. Journal of Chromatography A, 1339, 86-95. https://doi.org/10.1016/j.chroma.2014.02.077

A high-density, polymeric C18 stationary phase (Inertsil ODS-P) or a polymeric C30 phase (Inertsil C30) provided improved resolution of the isomeric fatty acids (FAs), FA methyl esters (FAMEs), triacylglycerols (TAGs), and tocopherols with an increas... Read More about Effect of pressure on the selectivity of polymeric C18 and C30 stationary phases in reversed-phase liquid chromatography. Increased separation of isomeric fatty acid methyl esters, triacylglycerols, and tocopherols at high pressure.

Comparison of peak shape in hydrophilic interaction chromatography using acidic salt buffers and simple acid solutions (2014)
Journal Article
Heaton, J. C., Russell, J. J., Underwood, T., Boughtflower, R., & McCalley, D. V. (2014). Comparison of peak shape in hydrophilic interaction chromatography using acidic salt buffers and simple acid solutions. Journal of Chromatography A, 1347, 39-48. https://doi.org/10.1016/j.chroma.2014.04.026

The retention and peak shape of neutral, basic and acidic solutes was studied on hydrophilic interaction chromatography (HILIC) stationary phases that showed both strong and weak ionic retention characteristics, using aqueous-acetonitrile mobile phas... Read More about Comparison of peak shape in hydrophilic interaction chromatography using acidic salt buffers and simple acid solutions.

Comparison of the kinetic performance and retentivity of sub-2μm core-shell, hybrid and conventional bare silica phases in hydrophilic interaction chromatography (2014)
Journal Article
Heaton, J. C., & McCalley, D. V. (2014). Comparison of the kinetic performance and retentivity of sub-2μm core-shell, hybrid and conventional bare silica phases in hydrophilic interaction chromatography. Journal of Chromatography A, 1371, 106-116. https://doi.org/10.1016/j.chroma.2014.10.013

© 2014 Elsevier B.V. The separation performance and retention properties of four sub-2μm underivatised silica materials were evaluated in the hydrophilic interaction chromatography (HILIC) mode. These included an organic/inorganic hybrid silica, conv... Read More about Comparison of the kinetic performance and retentivity of sub-2μm core-shell, hybrid and conventional bare silica phases in hydrophilic interaction chromatography.

Practical observations on the performance of bare silica in hydrophilic interaction compared with C18 reversed-phase liquid chromatography (2013)
Journal Article
Heaton, J. C., Wang, X., Barber, W. E., Buckenmaier, S. M., & McCalley, D. V. (2014). Practical observations on the performance of bare silica in hydrophilic interaction compared with C18 reversed-phase liquid chromatography. Journal of Chromatography A, 1328, 7-15. https://doi.org/10.1016/j.chroma.2013.12.058

The kinetic performance of a bare silica and C18 phase prepared from the same sub-2. μm and 3.5. μm base materials were compared in the HILIC and RP mode using both charged and neutral solutes. The HILIC column was characterised using the neutral sol... Read More about Practical observations on the performance of bare silica in hydrophilic interaction compared with C18 reversed-phase liquid chromatography.

Influence of phase type and solute structure on changes in retention with pressure in reversed-phase high performance liquid chromatography (2013)
Journal Article
Fallas, M. M., Tanaka, N., Buckenmaier, S. M., & McCalley, D. V. (2013). Influence of phase type and solute structure on changes in retention with pressure in reversed-phase high performance liquid chromatography. Journal of Chromatography A, 1297, 37-45. https://doi.org/10.1016/j.chroma.2013.04.006

The influence of pressure on the retention of several types of solute, including acids, bases and neutrals, was studied by the use of restriction capillaries added to the end of various monomeric and polymeric octadecylsilyl-modified 5. μm particle s... Read More about Influence of phase type and solute structure on changes in retention with pressure in reversed-phase high performance liquid chromatography.