Fabrication of adhesive coated swabs for improved swipe-based particle collection efficiency

Abstract

Improving particle collection efficiency for swipe-based sampling systems can provide a better chance of detection when screening for trace explosives or narcotics particles. A technique was developed to improve the particle collection efficiency of commercially-available collection swabs used for field sampling of trace contraband materials. A silicone adhesive was added to Teflon-coated fiberglass swabs to aid in collecting trace levels of contamination from surfaces. Since the swabs are typically used for ion mobility spectrometry (IMS) analysis, it is important for them to produce no chemical background when heated. Results show that the adhesive swabs had a higher particle collection efficiency compared to the untreated swabs by a factor of 12, without negatively interfering with the IMS analysis. It was also found that the adhesive swabs could be reused 10 times without significant reduction in collection efficiency. While it is possible that the adhesive swabs may not be suitable for all surface types due to loss of adhesive material after multiple uses, the benefits of higher particle collection efficiency are extremely promising.