Precolumn derivatization followed by liquid chromatographic separation and determination of tramiprosate in rat plasma by fluorescence detector: application to pharmacokinetics.

Alzheimer disease (AD) is characterized pathologically by extracellular amyloid deposits composed of amyloid β (Aβ) protein. A simple and rapid method using HPLC with fluorescence detector was developed and validated for determination of tramiprosate in rat plasma. Pre-column derivatization of the deproteinized rat plasma was carried out using o-phthaldialdehyde (OPA) as a fluorescent reagent in presence of 3-mercaptopropionic acid. The liquid chromatographic separation was achieved on a Kromasil C18 column using methanol:acetonitrile: 20 mM phosphate buffer pH 7.5 (8.0:17.5:74.5 v/v/v) as a mobile phase in an isocratic elution mode. The eluents were monitored by a fluorescence detector set at 330 and 450 nm of excitation and emission wavelength respectively. Vigabatrin was used as an internal standard. The method was linear within the range 30.0-1000.0 ng/mL. Design of experiments (DOE) was used to evaluate the robustness of the method. The developed method was applied to study the pharmacokinetics of tramiprosate in rats.