| Title: | Non-invasive sorptive extraction for the separation of human skin surface chemicals using comprehensive gas chromatography coupled to time-of-flight mass spectrometry: A mosquito-host biting site investigation |
| Author(s): | Wooding M; Rohwer ER; Naude Y; |
| Address: | "Department of Chemistry, University of Pretoria, Pretoria, Gauteng, South Africa" |
| ISSN/ISBN: | 1615-9314 (Electronic) 1615-9306 (Linking) |
| Abstract: | "Variation in inter-human attractiveness to mosquitoes, and the preference of mosquitoes to bite certain regions on the human host, are possible avenues for identifying lead compounds as potential mosquito attractants or repellents. We report a practical, non-invasive method for the separation and detection of skin surface chemical compounds and comparison of skin chemical profiles between the ankle and wrist skin surface area sampled over a 5-day period of a human volunteer using comprehensive gas chromatography coupled to time-of-flight mass spectrometry. An in-house made polydimethylsiloxane passive mini-sampler, worn as an anklet or a bracelet, was used to concentrate skin volatiles and semi-volatiles prior to thermal desorption directly in the gas chromatography. A novel method for the addition of an internal standard to sorptive samplers was introduced through solvent modification. This approach enabled a more reliable comparison of human skin surface chemical profiles. Compounds that were closely associated with the wrist included 6-methyl-1-heptanol, 3-(4-isopropylphenyl)-2-methylpropionaldehyde, 2-phenoxyethyl isobutyrate, and 2,4,6-trimethyl-pyridine. Conversely, compounds only detected on the ankle region included 2-butoxyethanol phosphate, 2-heptanone, and p-menthan-8-ol. In addition to known human skin compounds we report two compounds, carvone and (E)-2-decenal, not previously reported. Limits of detection ranged from 1 pg (carvone) to 362 pg (indole)" |
| Keywords: | Adsorption Animals Culicidae Gas Chromatography-Mass Spectrometry *Host-Parasite Interactions Humans *Insect Bites and Stings Particle Size Skin/*chemistry Surface Properties Volatile Organic Compounds/*analysis comprehensive screening mosquito semiochemi; |
| Notes: | "MedlineWooding, Madelien Rohwer, Egmont R Naude, Yvette eng Germany 2020/09/10 J Sep Sci. 2020 Nov; 43(22):4202-4215. doi: 10.1002/jssc.202000522. Epub 2020 Oct 1" |
