R. Karlicek et P. Solich, FLOW-INJECTION SPECTROPHOTOMETRIC DETERMINATION OF CAPTOPRIL USING ONLINE SOLID-PHASE EXTRACTION, Die Pharmazie, 53(8), 1998, pp. 549-551
In the proposed procedure, the determination of captopril with Folin-C
iocalteau reagent using a flow-injection analysis technique (FIA) with
spectrophotometric detection at 740 nm is described. The negative eff
ect of interfering substances is overcome by a solid phase extraction
(SPE), when captopril is adsorbed on the solid phase in the microcolum
n, which is integrated directly into the flow system. Pretreatment of
the sample takes place directly in the flowing stream. With the SPE co
lumn (quarternary ammonium), captopril was determined in the range fro
m 2 to 50 mu g/ml (RSD = 0.85%) with a frequency of 30 to 60 samples p
er hour.