S-perindopril assay using a potentiometric, enantioselective membrane electrode.
A potentiometric, enantioselective membrane electrode based on graphite paste (graphite powder and paraffin oil) has been constructed. The graphite paste is impregnated with a 10(-3) mol/L 2-hydroxy-3-trimethylammoniopropyl-beta-cyclodextrin (as chloride salt) solution. The potentiometric, enantioselective membrane electrode can be used reliably for enantiopurity tests of S-perindopril using a chronopotentiometric (zero current) technique, in the 10(-5)-10(-2) mol/L concentration range (detection limit 5 x 10(-6) mol/L), with an average recovery of 99.58% (RSD = 0.33%). The enantioselectivity was determined over R-perindopril and D-proline. The response characteristics of the enantioselective, potentiometric membrane electrode were also determined for R-perindopril. It was shown that L-proline is the main interfering compound. The surface of the electrode can be regenerated simply by polishing, obtaining a fresh surface ready to be used in a new assay.
Stefan
R I
RI
Department of Chemistry, University of Pretoria, Pretoria 0002, South Africa.
Van Staden
J K
JK
Aboul-Enein
H Y
HY
D000806:Angiotensin-Converting Enzyme Inhibitors / Q000032:analysis*; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D020913:Perindopril / Q000032:analysis*; D011199:Potentiometry; D013237:Stereoisomerism
D000806:Angiotensin-Converting Enzyme Inhibitors; D020913:Perindopril