Determination of terpene trilactones in Ginkgo biloba solid oral dosage forms using HPLC with evaporative light scattering detection

A reversed phase high performance liquid chromatographic method with evaporative light scattering detection (RP-HPLC-ELSD) was developed for the quantitative determination of the terpene trilactones, ginkgolide A, 13, C and J and the sesquiterpene, bilobalide in Ginkgo biloba solid oral dosage forms. Separation was achieved using a minibore Phenomenex Luna (5 mu n) C-18 column with dimensions 250 mm x 2.00 mm maintained at a temperature of 45 degrees C. A simple gradient method using a mobile phase of methanol:water and a flow rate of 350 mu l/min facilitated baseline separation of the selected marker compounds within 14 min. The ELSD parameters affecting the detector response were optimized prior to the validation. The lit-nits of detection and quantification were 31.25 and 62.50 ng, respectively. The percentage relative errors of the recovery ranged between -3.16 and +1.88 and both intra-day and inter-day percentage standard deviations were all better than 6%. This method was used to assay commercially available Ginkgo biloba products and proved to be suitable for the routine analysis of such products for quality control purposes. (c) 2005 Elsevier B.V. All rights reserved.