The column may then be inverted and irrigated internally with a wash buffer to remove {HEAD ~ unhomogenized macroscopic tissue material} and {TAIL ~ unbound residual cells} 
The column may then be inverted and irrigated internally with a wash buffer to remove { HEAD ~ unhomogenized macroscopic tissue material } and { TAIL ~ unbound residual cells }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL