The invention is directed to an oral biological preparation for specific delivery in colon, especially an oral insulin preparation for {HEAD ~ specific delivery} in {TAIL ~ colon} 
in
The invention is directed to an oral biological preparation for specific delivery in colon , especially an oral insulin preparation for { HEAD ~ specific delivery } in { TAIL ~ colon }
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 REL TAIL TAIL TAIL TAIL TAIL