Method transfer from high-pressure liquid chromatography to ultra-high-pressure liquid chromatography. II. Temperature and pressure effects

Åsberg, Dennis; Samuelsson, Jörgen; Leśko, Marek; Cavazzini, Alberto; Kaczmarski, Krzysztof; Fornstedt, Torgny

doi:10.1016/j.chroma.2015.05.002

Cited by 28 publications

(24 citation statements)

References 28 publications

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“…Much smaller effect has been reported for the retention of uncharged solutes compared to charged solutes with the pressure increase in a similar range [13]. Present results showed a large increase in retention for tocopherols that are uncharged solutes with larger size.…”

Section: Effect Of Temperature On Selectivity Of Polymeric Ods Phasesupporting

confidence: 56%

“…The effect of pressure on solute retention is strongly affected by the combination of solute structure and stationary phase structure. The effect of pressure was shown to be more pronounced for charged solutes [13,14]. For small, uncharged, hydrophobic solutes, the effects were relatively small.…”

Section: Introductionmentioning

confidence: 87%

“…Effects of higher pressure or lower temperature on selectivity have been observed in reversed-phase liquid chromatography [11,12,13,14]. The effect of pressure on solute retention is strongly affected by the combination of solute structure and stationary phase structure.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

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

Yui¹,

Miyazaki²,

et al. 2016

Journal of Chromatography A

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Section: Effect Of Temperature On Selectivity Of Polymeric Ods Phasesupporting

confidence: 56%

Section: Introductionmentioning

confidence: 87%

See 1 more Smart Citation

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

Yui¹,

Miyazaki²,

et al. 2016

Journal of Chromatography A

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“…The computed properties 16) showed that the hydrogen bond donor count, rotatable bond count, and topological polar surface area of cyclosporine A were smaller, while the calculated log P value was larger, than those of daptomycin and Des-Arg9-[Leu8]-bradykinin (Table 2). These physicochemical characteristics, which contribute to the favorable pharmaceutical properties of cyclosporine A, result from the following key structural features-1: its cyclic backbone structure and incorporation of a D-amino acid, which protect against proteolytic degradation and increase structural rigidity, 2: seven N-methyl groups, which reduce the number of amide groups available to act as hydrogen bond donors, and 3: intramolecular hydrogen bonds, which reduce the availability of amide NH protons.…”

Section: )mentioning

confidence: 99%

“…20) Therefore, at higher temperature, the increase in these rates results in an increase in the mass transfer rate, which in turn causes a sharpening of the peak shape and increase of the plate number. 17) This temperature effect, in addition to the use of a nonporous column, must contribute to the highly efficient analysis of cyclosporine A. Furthermore, decreasing the particle size also contributes to the decreases in the A and C terms of Eq.…”

Section: )mentioning

confidence: 99%

Rapid Analysis of Cyclic Peptide Cyclosporine A by HPLC Using a Column Packed with Nonporous Particles

Sakai‐Kato¹,

Nanjo²,

Goda³

2018

CHEMICAL & PHARMACEUTICAL BULLETIN

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We developed a rapid and efficient analytical technique for cyclosporine A using HPLC on a column packed with 2-µm nonporous octadecylsilyl silica particles. Under optimized conditions, cyclosporine A was separated with high resolution from other cyclic peptides within 3 min, because the mass transfer resistance in the stationary phase was reduced by the use of the small, nonporous particles. Although the plate number increased greatly with the increase in the column temperature, the retention times were not affected. This behavior is different from other cyclic peptides or linear peptides. Based on its physicochemical characteristics, cyclosporine A is a poor hydrogen bond donor, and has a small topological polar surface area, low rotatable bond count, and high log P value. These results show that cyclosporine A is structurally rigid and undergoes poor water solvation even at high temperature. In the context of the rapid development of cyclic peptides with similar physicochemical characteristics to cyclosporine A, our developed method is useful for the development of cyclic peptide therapeutics.

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Critical assessment of “critical” liquid chromatography of block copolymers

Berek

2016

J of Separation Science

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Brief elucidation is presented of potential difficulties the researcher can face in the course of the molecular characterization of block copolymers with help of liquid chromatography under critical conditions. The impediments include the demanding identification of critical conditions, the limited area of applicable polymer molar mass, the high sensitivity of critical conditions toward minute changes in experimental conditions including changes in the interactivity of the column packing, extensive band broadening, limited sample recovery, pressure effects, detection problems, coelution of block copolymers with their noninteractive parent homopolymers, possible effect of the noninteracting chains of block copolymers on the behavior of the interacting blocks, and role of preferential solvation of macromolecules in mixed solvents. These matters may complicate proper data evaluation and challenge the exactness of results obtained. Special attention is paid to the so far neglected phenomena of preferential solvation, which may affect not only detection of block copolymers but also their retention. The latter occurrence is demonstrated by the behavior of both poly(methyl methacrylate)s eluted from bare silica gel in a mixed eluent tetrahydrofuran plus toluene and polystyrenes eluted from silica gel C18 bonded phase with the mobile phase of tetrahydrofuran/n-hexane.

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Method transfer from high-pressure liquid chromatography to ultra-high-pressure liquid chromatography. II. Temperature and pressure effects

Cited by 28 publications

References 28 publications

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

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

Rapid Analysis of Cyclic Peptide Cyclosporine A by HPLC Using a Column Packed with Nonporous Particles

Critical assessment of “critical” liquid chromatography of block copolymers

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