When I started my Ph.D., I knew I needed a very portable, robust way of sampling plant volatiles in the field. I was going to be doing my work on tea farms in China, potentially far from a lab or even a source of electricity, so I didn’t want to rely on the typical plant volatile sampling method used at the time—dynamic headspace sampling. Dynamic headspace sampling requires a pump (and a power source) to pull or push air through a container placed around a plant or plant part, then through a sorbent tube that traps the volatiles. Besides not being easily portable and having replication limited somewhat by the number of pumps, this method introduces a lot of opportunity for contamination from the chamber materials, loss of volatiles due to breakthrough on the sorbent tube, and puts plants in an unnatural environment (in a hot, UV-filtered glass bottle or plastic bag). In collaboration with Nicole Kfoury, a graduate student in Albert Robbat’s lab in the Tufts Chemistry department, we created and tested a new application for the magnetic sorptive stir bars (Twisters) they used routinely for sampling volatiles from liquids. We though “Hey, these Twisters are magnetic. Could we just stick them on a plant leaf with a magnet on the other side and sample leaf volatiles?” I brought some Twisters with me on my first field season in China and that was the start of a wonderful collaboration that lead to the creation of a new robust, high-throughput method for sampling volatiles in the field that we call Direct Contact Sorptive Extraction, or DCSE for short.
Field-Sampling Plant Volatiles
Nicole Kfoury, Eric R. Scott, Colin Orians, Albert Robbat Jr. Direct Contact Sorptive Extraction: A Robust Method for Sampling Plant Volatiles in the Field. J Agric Food Chem, 2017.