{HEAD ~ The photocrosslinking} can use a sensitizer and {TAIL ~ exposure} to light to achieve crosslinking 
{ HEAD ~ The photocrosslinking } can use a sensitizer and { TAIL ~ exposure } to light to achieve crosslinking
HEAD HEAD HEAD HEAD HEAD HEAD OTH REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH