Simultaneous quantification of different cyclodextrins and Gantrez by HPLC with evaporative light scattering detection.

A rapid and simple HPLC method with evaporative scattering detection (ELSD) has been developed for the separation and quantitation of beta-cyclodextrin (beta-CD), 2-hydroxypropyl-beta-cyclodextrin (2-HP-beta-CD) and poly(methyl vinyl ether-co-maleic anhydride) (Gantrez). Separation was carried out on a Zorbax Eclipse XDB-Phenyl narrow bore column, with water-acetonitrile in gradient elution as mobile phase at a flow-rate of 0.25 ml/min. Polyethylenglycol 6000 was used as internal standard. The limit of quantification was of about 0.2 mg/ml for cyclodextrins and 0.05 mg/ml for Gantrez. The precision did not exceed 7%. This method was successfully applied to the rapid analysis of CD-Gantrez nanoparticle conjugates without interference from other components of the formulation.