| Abstract: | ![]()
A new method is described for the determination of famotidine by solid phase extraction from alkalinized human plasma followed by reversed phase (RP) HPLC in acetonitrile/alkaline buffer with molsidomine as an internal standard. Different acetonitrile/aqueous buffer mobile phases as well as various RP columns were used. Alkaline medium allowed the limit of quantitation to be lowered to 5 ng/mL of plasma as the famotidine gives more intense absorption at about 286 nm (at pH values higher than 7). Moreover, work in alkaline media and at this wavelength is highly selective as peaks corresponding to impurities present in most samples are well separated. A method using a mildly alkaline mobile phase (acetonitrile/10 mM phosphate with 10 mM 1‐heptanesulphonic acid, pH 7.5) was successfully used for determination of famotidine in human plasma in a pharmacokinetic study. |
