Analysis of Cyclodextrines in Green Tea using HPLC-ELSD

Download PDF August 25, 2017

Introduction

An evaporative light scattering detector (ELSD) is an universal detector for HPLC which detects the scattered light from the particles when illuminated from the non-volatile substance that remains after the sample is sprayed together with N2 gas. LED is used as a light source to illuminate the non-volatile particles, and the light scattered will be collected and converted into the electronic signal by photomultiplier tube. Samples such as sugar and fat which can only be detected at short, noisy UV wavelengths, or by an insensitive, isocratic requiring RI detector can be measured with high sensitivity and stable baseline by ELSD. Cyclodextrine is known as the oligosaccharide with its glucoses being connected in circle. Cyclodextrine is further named as a-Cyclodextrine, b-Cyclodextrine and g-Cyclodextrine for the cases that the number of glucoses becomes 6, 7, or 8. Since the properties and the performance of each are different according to the number of glucoses, the amount of these cyclodextrines will influence the taste of food.

This report describes the analysis of cyclodextrine using ELSD with a polymer NH2 column in HILIC mode.

Experimental

Results

Figure 1 shows the chromatogram of a, b, g-Cyclodextrine.

Figure 1. Chromatogram of the standard mixture of Cyclodextrine
1: a-Cyclodextrine , 2: g-Cyclodextrine , 3: b-Cyclodextrine

Figure 2 shows the chromatogram of green tea mixed with cyclodextrine. All the components were detected with the quantitative result : a-Cyclodextrine 4.5 mg/10mL, b-Cyclodextrine 5.0 mg/10mL, g-Cyclodextrine 22.7 mg/10mL.

Figure 2. Chromatogram of green tea mixed with cyclodextrine
1: a-Cyclodextrine , 2: g-Cyclodextrine , 3: b-Cyclodextrine

Sample preparation: Green tea combined with cyclodextrine was mixed with mobile phase of the same amount and was then sent through a 0.45µm filter.

About the Author

Miyuki Kanno