A silica gel based method for extracting insect surface hydrocarbons

J Chem Ecol. 2012 Feb;38(2):176-87. doi: 10.1007/s10886-012-0074-1. Epub 2012 Feb 12.

Abstract

Here, we describe a novel method for the extraction of insect cuticular hydrocarbons using silica gel, herein referred to as "silica-rubbing". This method permits the selective sampling of external hydrocarbons from insect cuticle surfaces for subsequent analysis using gas chromatography-mass spectrometry (GC-MS). The cuticular hydrocarbons are first adsorbed to silica gel particles by rubbing the cuticle of insect specimens with the materials, and then are subsequently eluted using organic solvents. We compared the cuticular hydrocarbon profiles that resulted from extractions using silica-rubbing and solvent-soaking methods in four ant and one bee species: Linepithema humile, Azteca instabilis, Camponotus floridanus, Pogonomyrmex barbatus (Hymenoptera: Formicidae), and Euglossa dilemma (Hymenoptera: Apidae). We also compared the hydrocarbon profiles of Euglossa dilemma obtained via silica-rubbing and solid phase microextraction (SPME). Comparison of hydrocarbon profiles obtained by different extraction methods indicates that silica rubbing selectively extracts the hydrocarbons that are present on the surface of the cuticular wax layer, without extracting hydrocarbons from internal glands and tissues. Due to its surface specificity, efficiency, and low cost, this new method may be useful for studying the biology of insect cuticular hydrocarbons.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adsorption
  • Animals
  • Ants / anatomy & histology*
  • Ants / chemistry*
  • Bees / anatomy & histology*
  • Bees / chemistry*
  • Chemical Fractionation / methods*
  • Gas Chromatography-Mass Spectrometry
  • Hydrocarbons / chemistry
  • Hydrocarbons / isolation & purification*
  • Hydrophobic and Hydrophilic Interactions
  • Reproducibility of Results
  • Silica Gel / chemistry*
  • Solvents / chemistry

Substances

  • Hydrocarbons
  • Solvents
  • Silica Gel