i) {HEAD ~ a linear polymer} selected from {TAIL ~ the group} consisting of linear hydrophobic biodegradable polymers and linear non degradable hydrophilic polymers 
selected from
i ) { HEAD ~ a linear polymer } selected from { TAIL ~ the group } consisting of linear hydrophobic biodegradable polymers and linear non degradable hydrophilic polymers
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH