Microquantitative separation of isomeric dimethyltocols by gas-liquid chromatography

Nair, Padmanabhan P.; Sarlos, I.J.; Machiz, Joan

doi:10.1016/0003-9861(66)90372-9

Cited by 29 publications

(9 citation statements)

References 9 publications

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“…Nair et al (56) achieved microquantitative separation of isomeric dimethyltocols with the SE-52/XE-60 biphase column used by Nair and Turner (45) as discussed above. 3,-Tocopherol was separated from /3-tocopherol as the paraquinones.…”

Section: Vitamin Ementioning

confidence: 99%

“…Nair and Luna (68) have studied the identification of 0~-tocopherol from tissues by combined GLC, mass spectrometry and 1R spectroscopy. The GLC vitamin E analysis was that previously reported from Nair's laboratory (45,56,57) in which the binary mixture of SE-52 and XE-60 was used. 0t-Tocopherol isolated from heart muscle was characterized by the combined system.…”

Section: Vitamin Ementioning

confidence: 99%

See 1 more Smart Citation

Gas chromatography of the fat‐soluble vitamins: A review

Sheppard

Prosser

Hubbard

1972

J Americ Oil Chem Soc

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The application of gas liquid chromatography (GLC) as an analytical tool for the determination of the fat-soluble vitamins A, D, E and K has yet to be utilized to its full potential. A review of the published work of many researchers in this field is presented. GLC methods to measure the vitamin A isomers have not been developed to any appreciable practical extent. Liquid liquid chromatography might well be the technique of choice. In the field of vitamin D there are indications that a practical GLC analysis is feasible for pharmaceutical preparations. The GLC applications for vitamin E are diverse, well defined and generally widely accepted in research laboratory situations and for regulatory and quality control usage. Vitamins K 1 and K 2 have been measured with limited success in a few research laboratories, but the GLC methods have not developed on a practical basis. However GLC is used for measuring vitamin K 3 (menadione and menadione sodium bisulfite) on a fairly routine basis in quality control laboratories.

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Section: Vitamin Ementioning

confidence: 99%

Section: Vitamin Ementioning

confidence: 99%

Gas chromatography of the fat‐soluble vitamins: A review

Sheppard

Prosser

Hubbard

1972

J Americ Oil Chem Soc

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“…Column chromatography on Florisil was used prior to GLC. Nair and coworkers have made significant advances in improving the sensitivity and reproducibility of GLC techniques for tocopherols (49,50). Their work involved an extensive investigation of the GLC properties of the tocopherols, tocopherol quinones, the trimethylsilylethers, and the acetate, propionate, trifluoracetate and pentafluoropropionate esters.…”

Section: Gas Liquidmentioning

confidence: 99%

Modern procedures for the analysis of tocopherols

Bunnell

1971

Lipids

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The development of reliable assay methodology for the tocopherols has been an evolutionary process which has required over 40 years to reach its present state. Today the analyst has at his disposal a choice of reliable and accurate methods of analysis for the eight tocopherols now known to exist in nature. The general sequence of procedure and the precautions to be observed are described. After suitable extraction procedures and careful saponification techniques, the tocopherols in the nonsaponifiable fraction can be assayed by a variety of chromatographic procedures including paper, thin layer (TLC), column and gas liquid chromatography (GLC). The current methodology of these procedures is reviewed in some detail with special emphasis on the more frequently used TLC and GLC techniques. The earlier methods of GLC assay separated only the mono‐, di‐ and trimethylated tocopherols but methods are now available which provide separation of all the tocopherols. These developments were made possible by better columns and the use of derivatives of tocopherols. In addition to good separation, the GLC method is the most sensitive available for the quantitation of the tocopherols. Spectrophotometric measurements based on Emmerie Engel type reactions have been most frequently used for the final quantitative analysis of the tocopherols separated by paper, TLC, or column chromatography.

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“…Although GC [10], CE [23,24] and RP HPLC, with standard C8 or C18 stationary phases [15][16][17][18], showed good separation efficiency, these techniques do not have sufficient selectivity for separation of the b-and g-isomers. Only partial separation of the b-and g-TOHs was observed using a packed C30 stationary phase using HPLC [21].…”

Section: Introductionmentioning

confidence: 98%

“…There have been various methods reported for the quantitative analysis of TOHs, including GC [10], HPLC [11][12][13][14][15][16][17][18][19][20][21][22], CE [23,24] and CEC [25][26][27][28][29][30]. Due to the structural similarities of the b-and g-isomers (positional isomers), separation of these compounds is therefore challenging.…”

Section: Introductionmentioning

confidence: 99%

Separation of α‐, β‐, γ‐, δ‐tocopherols and α‐tocopherol acetate on a pentaerythritol diacrylate monostearate‐ethylene dimethacrylate monolith by capillary electrochromatography

et al. 2008

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This work reports the first use of a monolith with method development for the separation of tocopherol (TOH) compounds by CEC with UV detection. A pentaerythritol diacrylate monostearate-ethylene dimethacrylate (PEDAS-EDMA) monolithic column has been investigated for an optimised condition to separate alpha-, beta-, gamma- and delta-TOHs, and alpha-tocopherol acetate (TAc). The PEDAS-EDMA monolith showed a remarkably good selectivity for separation of the TOH isomers including the beta- and gamma-isomers which are not easily separated by standard C8 or C18 particle-packed columns. Retention studies indicated that an RP mechanism was involved in the separation on the PEDAS-EDMA column, but polar interactions with the underlying ester and hydroxyl groups enhanced the separation of the problematic beta- and gamma-isomers. Separation of all the compounds was achieved within 25 min using 3:10:87 v/v/v 100 mM Tris buffer (pH 9.3)/methanol/ACN as the mobile phase. The method was successfully applied to a pharmaceutical sample with recoveries from 93 to 99%. Intraday and interday precisions (%RSD) for peak area and retention time were less than 2.3. LODs for all four TOHs and TAc were below 1 ppm.

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Microquantitative separation of isomeric dimethyltocols by gas-liquid chromatography

Cited by 29 publications

References 9 publications

Gas chromatography of the fat‐soluble vitamins: A review

Gas chromatography of the fat‐soluble vitamins: A review

Modern procedures for the analysis of tocopherols

Separation of α‐, β‐, γ‐, δ‐tocopherols and α‐tocopherol acetate on a pentaerythritol diacrylate monostearate‐ethylene dimethacrylate monolith by capillary electrochromatography

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