Development and validation of a simple high performance liquid chromatography – evaporative light scattering detector method for direct quantification of native cyclodextrins in a cyclization medium

• A HPLC–ELSD method was developed for the separation and direct quantification of native CDs.
• CDs were rapidly separated using a NUCLEODUR® C18 Pyramid column at 30 °C.
• The HPLC–ELSD method used water-rich mobile phase.
• Liquefied starch, dextrins, and glucose did not interfere in the CD quantification.
• α-CD, γ-CD, and β-CD were accurately quantified directly from a real system.

A simple HPLC–ELSD method was developed for the separation and quantification of native cyclodextrins. The technique was validated in the presence of two interfering matrices composed of byproducts from the cyclization medium. A fast separation of the compounds was achieved (in <20 min) using a NUCLEODUR® C18 Pyramid column (150 mm × 4.6 mm; particle size 5 μm) at 30 °C. The analytes were eluted using a linear gradient of acetonitrile and water containing 1% (v/v) of acetic acid at a flow rate of 0.3 mL/min. Validation results showed that the method was accurate (93–110%) and selective. The precision was ≤5.7% for a hydrolyzed starch blank matrix spiked with cyclodextrins, and ≤6.2% for a blank matrix composed of a mixture of dextrin and glucose spiked with cyclodextrins. The limit of quantification was 0.05 g/L for alpha- and 0.06 g/L for beta- and gamma-cyclodextrins. The new HPLC–ELSD method could accurately quantify the three cyclodextrins directly in a cyclization medium, without pretreatment of the samples.