The liposomes have an inside/outside ion gradient sufficient to retain the topoisomerase I inhibitor or topoisomerase I/II inhibitor within {HEAD ~ the liposomes} at {TAIL ~ the specified concentration} 
The liposomes have an inside / outside ion gradient sufficient to retain the topoisomerase I inhibitor or topoisomerase I / II inhibitor within { HEAD ~ the liposomes } at { TAIL ~ the specified concentration }
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 REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL