{HEAD ~ Biological substances} are observed by employing {TAIL ~ a high internal gradient magnetic capture structure} formed within a vessel, in conjunction with an externally applied force for transporting magnetically responsive material toward the capture structure 
are observed by employing
{ HEAD ~ Biological substances } are observed by employing { TAIL ~ a high internal gradient magnetic capture structure } formed within a vessel , in conjunction with an externally applied force for transporting magnetically responsive material toward the capture structure
HEAD HEAD HEAD HEAD HEAD HEAD REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH