Alternatively, other targeting devices may be used such as attachment of the amplifier to {HEAD ~ a porphyrin} or {TAIL ~ other tumor} seeking moiety 
Alternatively , other targeting devices may be used such as attachment of the amplifier to { HEAD ~ a porphyrin } or { TAIL ~ other tumor } seeking moiety
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH