Evaluation of a robotic transfer replicator: machine parameters that affect measurements of transfer of particulates from carpet surfaces to human skin versus human skin-like surfaces

Abstract

We have designed and built a robotic machine (robotic transfer replicator) to replicate the process by which various particulates are transferred from carpet surfaces to human skin. The particulates tested included bovine serum albumin, dust mites, paint dust, pesticides, and pollen. We have investigated the effect of time of transfer, applied pressure, skin-like receptor materials, particulate size, carpet composition and construction, and motion of the receptors on the percent transfer. The amount transferred was determined to be directly proportional to the amount of particulate applied to the carpet surface. The percent transfer values ranged from 0.05% to 28% for different combinations of particulates, carpet types, and method of transfer. The percent transfer was shown to be independent of receptor size or applied pressure. To explain the variations in the percent transfer, a three-zone model for particulate penetration into carpets is proposed. While the robotic transfer replicator was not capable of reproducing exactly the results from human finger transfer, it does provide a controlled and reproducible approach to the transfer process and the ability to use toxic or pathogenic materials that could not be used with human subjects.