Improved Swab Design for Contact Sensing

Download Project Report (Phase 2, Year 4)

Project Description

Contact sampling is at the heart of current methods of explosives interdiction at air transportation venues.  This involves the use of ‘swabs’ or ‘wipes’ which are passed over surfaces of interest, such as purses and laptops, to collect any possible residues of explosives that were deposited by a potential terrorist.

The swabs are then passed through an ion mobility spectrometer where they are rapidly heated to roughly 250°C to desorb any residue, which is subsequently detected in the spectrometer.  Swabs can then be reused to detect residue on the next item.  Current swabs are optimized to survive the high temperatures of the desorber, but not to interrogate surfaces.

This project develops meso-engineered polymeric swabs with customized surface topography, electrical properties, mechanical properties, and surface chemistry, to provide superior residue harvesting capabilities.  Prototype swabs have been assembled and are undergoing testing.  Second generation swabs are being developed with a focus on optimizing the surface topography of the swabs.

A detailed study of the topography of common surfaces is being conducted to inform this swab topography work, so that a single swab can be developed offering outstanding performance on a wide range of surfaces.  A similar detailed study is underway to evaluate the effect of different surface chemistries on the harvesting.


This project seeks to develop swabs that do the best possible job of harvesting residues from surfaces.
2016 Biennial Review
Project Leader
  • Stephen P. Beaudoin
    Purdue University

Faculty and Staff Currently Involved in Project
  • Byran Boudouris
    Assistant Professor
    Purdue University

Students Currently Involved in Project
  • Melissa Sweat
    Purdue University
  • Darby Hoss
    Purdue University
  • Sean Fronczak
    Purdue University
  • Jennifer Laster
    Purdue University
  • Jordan Thrope
    Lafayette Jefferson High School