For example, the functional unit may independently or in combination with {TAIL ~ the nucleic acid unit} have specific affinity for the target, and in some cases may be a ligand to a different site of interaction with the target than {HEAD ~ the nucleic acid ligand} 
For example , the functional unit may independently or in combination with { TAIL ~ the nucleic acid unit } have specific affinity for the target , and in some cases may be a ligand to a different site of interaction with the target than { HEAD ~ the nucleic acid ligand }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH 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 OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD