KCS

Volatile organic compounds are generally small molecules and emitted from various sources including food, cosmetics, environment and many different mediums. They can be considered as a significant indicator of freshness, quality control, and/or level of pollution. Needle-based headspace extraction methods have been investigated and a novel in-needle micro-extraction (INME) with polydimethylsiloxane (PDMS)-based coatings has been proposed. INME needle is easy to handling and inexpensive to fabricate. Depending coating materials in needle, the selectivity and extraction efficiency of both polar and non-polar compounds were enhanced. In addition, the micro-bore tunnel generated from filling the needle with the coating materials enhanced the sorption of compounds. The various PDMS-based coating materials were investigated to optimize the conditions for target compounds. Through this study, the coating phase/sample distribution constant, the volume of coating phase, the coating thickness, the diameter of the micro-bore tunnel, and length of the coating phase in the needle, and extraction time were found to be significant parameters for optimization of needle design and extraction efficiency. The proposed INME method with various coating materials was properly validated.