Chinese lovage root, gao ben (root) HPTLC ID - UV 254 nm

Chinese lovage root, gao ben (root) (Ligusticum sinense, Ligusticum jeholense)

Lane Assignments Lanes, from left to right (Track, Volume, Sample):

1. 4 µL Imperatorin, z-Ligustilide (incr. Rf)
2. 4 µL Osthole
3. 4 µL Angelica root 1*
4. 4 µL Angelica root 2
5. 4 µL Angelica root 3
6. 4 µL Chinese Angelica root
7. 4 µL Dahurian Angelica root
8. 4 µL Doubleteeth pubescent Angelica root 1
9. 4 µL Doubleteeth pubescent Angelica root 2
10. 4 µL Lovage root 1*
11. 4 µL Lovage root 2
12. 4 µL Lovage root 3
13. 4 µL Chinese lovage root (Ligusticum sinensis)
14. 4 µL Chinese lovage root 1 (Ligusticum jeholense)
15. 4 µL Chinese lovage root 2 (Ligusticum jeholense)
16. 4 µL Chinese lovage root (Ligusticum chuanxiong) 

Reference Sample(s) Reference: Dissolve 1 mg each of osthole and imperatorin in 10 mL of methanol. Optional: Dissolve 1 mg of Z-ligustilide in 10 mL of methanol. 

Stationary Phase Stationary phase, i.e. Silica gel 60, F254 

Mobile Phase Toluene, ethyl acetate, glacial acetic acid 90:10:1 (v/v/v) 

Sample Preparation Method Sample: Mix 1.0 g of powdered sample with 4 mL of heptane and sonicate for 5 minutes, then centrifuge and filter the solutions and use the filtrates as test solutions.

Derivatization reagent: Sulfuric acid reagent; Preparation: 20 mL sulfuric acid with 180 mL methanol; Use: Dip for 1 s, heat at 100°C for 5 min 

Detection Method Saturated chamber; developing distance 70 mm from lower edge; relative humidity 33% 

Other Notes Images presented in this entry are examples and are not intended to be used as basis for setting specifications for quality control purposes.

System suitability test: Imperatorin: greenish fluorescent zone at Rf ~ 0.31 (UV 366 nm); Osthole: blue fluorescent zone at Rf ~ 0.36 (UV 366 nm).

Identification: Compare result with reference images. The fingerprint of the test solution is similar to that of the corresponding botanical reference sample. Additional weak zones may be present. Under UV 254 nm the chromatogram of the test solution shows a weak blue fluorescent zone at Rf ~ 0.57 (red arrow). A weak quenching zone (Rf ~ 0.40) is seen above reference osthole. Under UV 366 nm the chromatogram of the test solution shows an intense light bluish fluorescent zone at Rf ~ 0.57 and a weak blue fluorescent zone with an Rf-value similar to reference imperatorin (yellow arrows). After derivatization under white light there are two prominent purple zones below the solvent front. Below reference imperatorin there is a very prominent, diffuse purple zones and another distinct purple zone right below (red arrows).

Test for adulteration: Under UV 254 nm no zone is seen at or directly below the position of imperatorin. After derivatization under white light no zone is seen at the position of osthole and below the two prominent purple zones (red arrows) there is no intense greenish zone (Angelica root, Chinese Angelica root, Doubleteeth pubescent root, Dahurian Angelica root, Lovage root).

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  Chinese lovage root, gao ben (root) HPTLC ID - UV 254 nm

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  Chinese lovage root, gao ben (root) HPTLC ID - UV 366 nm

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  Chinese lovage root, gao ben (root) HPTLC ID - Sulfuric acid, WRT

Source: HPTLC Association ^[1]