▁micro be ads ▁attach ▁themselves ▁to ▁the ▁magnetic ▁field ▁and ▁the ▁non - pa ired ▁cells ▁are ▁removed . ▁This ▁process ▁can ▁then ▁be ▁repeated ▁to ▁continue ▁removal ▁of ▁the ▁selected ▁cells . ▁ ▁SE P ▁system ▁provides ▁a ▁column - free ▁cell ▁separation ▁technique ▁in ▁which ▁a ▁t ube ▁of ▁l abeled ▁cells ▁is ▁placed ▁inside ▁a ▁magnetic ▁field . ▁Pos it ively ▁selected ▁cells ▁are ▁retained ▁in ▁the ▁t ube ▁while ▁neg atively ▁selected ▁cells ▁are ▁in ▁the ▁liquid ▁susp ension . ▁ ▁MAC S ▁devices ▁are ▁significantly ▁che aper ▁than ▁F AC S ▁devices ▁because ▁they ▁do ▁not ▁require ▁cells ▁to ▁be ▁focused ▁into ▁a ▁single ▁stream ▁and ▁instead ▁can ▁separate ▁cells ▁in ▁bulk . ▁This ▁method ▁suff ers ▁from ▁a ▁lower ▁target ▁cell ▁pur ity ▁due ▁to ▁ent rain ment ▁of ▁non - l abeled ▁cells ▁in ▁target ▁populations ▁and ▁highly ▁non ▁linear ▁magnetic ▁forces ▁that ▁causes ▁cells ▁far ▁from ▁the ▁source ▁to ▁be ▁poor ly ▁sorted . ▁However , ▁MAC S ▁has ▁shown ▁to ▁be ▁benef icial ▁when ▁used ▁with ▁N PC ▁( ne ural ▁pro gen itor ▁cell ) ▁cult ures ▁in ▁particular , ▁as ▁it ▁is ▁easier ▁to ▁manage ▁and ▁causes ▁minimal ▁damage ▁to ▁live ▁cells . ▁ ▁N PC ▁cult ures ▁are ▁especially ▁difficult ▁to ▁work ▁with ▁because ▁live ▁brain ▁cells ▁are ▁sensitive ▁and ▁tend ▁to ▁cont amin ate ▁each ▁other . ▁In ▁order ▁to ▁get ▁clearer ▁results , ▁l abs ▁need ▁cleaner ▁materials , ▁meaning ▁more ▁pure ▁N PC ▁lines . ▁A ▁study ▁done