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PubMed · 16854423

Sample preparation methods for beeswax characterization by gas chromatography with flame ionization detection.

J J Jiménez·J L Bernal·M A J del Nozal·M A T Martín·J Bernal
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Abstract

New and simpler methods of sample preparation to determine several families of compounds in beeswax by conventional and high temperature gas chromatography are proposed. To analyze hydrocarbons and palmitates, a dilution of sample is enough whereas for the total acid content, a hydrolysis and simultaneous methylation with BF3-methanol results more effective than the usual methods; for the total content of alcohols, a further acetylation with acetic anhydride is necessary. Free alcohols are directly acetylated in a sample dissolution but for free acids and monoesterified 1,2,3-propanetriols analysis, a previous extraction with acetonitrile is required. The concentrations of all the compounds studied are expressed in weight percentage referred only to one standard: octadecyl octadecanoate. The precision of the analytical methods has been evaluated showing its importance in the analysis of beeswaxes used in apiculture.

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AlcoholsChromatography, GasFlame IonizationHydrocarbonsPalmitatesReproducibility of ResultsWaxesJournal ArticleResearch Support, Non-U.S. Gov't

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J J Jiménez, J L Bernal, M A J del Nozal, M A T Martín, J Bernal. 2006-07-18. Sample preparation methods for beeswax characterization by gas chromatography with flame ionization detection.. https://doi.org/10.1016/j.chroma.2006.06.098

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