EFFECT OF PHOSPHOLIPIDS ON CARRIER-MEDIATED TRANSPORT OF LANTHANIDE IONS THROUGH CELLULOSE TRIACETATE MEMBRANES

Fluxes of 14 kinds of lanthanide ions across cellulose triacetate memb ranes were determined by using mixtures of o-nitrophenyl n-octyl ether and synthetic phospholipids as plasticizers, and 4-benzoyl-3-methyl-1 -phenyl-5-pyrazolone (BMPP) and hinokitiol (HIPT) as carriers. The pho spholipids used were didecanoyl-, dilauroyl-, and dimyristoyl-L-alpha- phosphatidylcholines. The effect of these phospholipids on the flux wa s demonstrated. The flux using BMPP increased with an increase in ioni c radius of the lanthanide and reached a maximum value at an ionic rad ius around that of dysprosium. Subsequently, it decreased and then inc reased again in the range of praseodymium to lanthanum. The variation in the flux decreased with an increase in alkyl chain length of the ph ospholipid. For HIPT, an appreciable increase in the flux was observed in the range of erbium to europium.