Fine Sieving of Collected Atmospheric Particles using Oil Electrophoresis (iSCAPE)

Abstract

It is rather challenging to separate atmospheric particles from nano-to micro-metre mixed in a sample. Here, a system named iSCAPE was invented to efficiently sieve particles out from a mixture by employing an electrostatic field and a non-conductive mineral oil. Tests with atmospheric particles of different cities as well as soil and road dust samples demonstrated that the iSCAPEd particles under different operating conditions moved rapidly with different velocities and both directions. Particles of different sources such as ambient air, soil or road were shown to have different polarity-charged particle fractions, and exhibited clearly different particle electrical mobility graphs after the iSCAPE sieving from seconds to minutes. Data also revealed that after the sieving some particles were enriched at specific mobility ranges. Bacterial ATP measurements implied that the iSCAPE can be also used to efficiently separate bacteria of different sizes and charge polarity. Experimental data here suggest that the iSCAPE sieving strongly replies on the electrostatic field strength, mineral oil viscosity and the run time. In theory, the iSCAPE system can be used to extract any desired targets from a complex sample, thus opening up many outstanding opportunities for environmental, biomedical and life science fields. TOC O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=69 SRC="FIGDIR/small/894998v1_ufig1.gif" ALT="Figure 1"> View larger version (21K): org.highwire.dtl.DTLVardef@8d50f9org.highwire.dtl.DTLVardef@1bf1b1aorg.highwire.dtl.DTLVardef@18c70ddorg.highwire.dtl.DTLVardef@145c317_HPS_FORMAT_FIGEXP M_FIG C_FIG