The coatings can be used for the delivery of an active ingredient or {HEAD ~ a combination} of {TAIL ~ active ingredients} 
of
The coatings can be used for the delivery of an active ingredient or { HEAD ~ a combination } of { TAIL ~ active ingredients }
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 TAIL