Source: MOBOT, Tropicos.org^[1]

Doubleteeth Pubescent Angelica (root) HPTLC ID - UV 254 nm

Doubleteeth Pubescent Angelica (root) (Angelica pubescens)

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 (these samples do not comply with Ph.Eur specifications)
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 (these samples do not comply with Ph.Eur specifications)
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 quenching zone corresponding to reference osthole (Rf ~ 0.36) (red arrow). There may be a quenching zone corresponding to imperatorin (dashed red arrow) and there may be a quenching zone at the position of z-ligustilide (but no fluorescent zone). There are several weak quenching zones below these zones. Under UV 366 nm the chromatogram of the test solution shows a white blue fluorescent zone at Rf ~ 0.57 and a prominent blue fluorescent zone corresponding to osthole (yellow arrows). Above this zone there may be a very faint green whitish zone. There may be a green whitish fluorescent zone corresponding to imperatorin (dashed yellow arrow). Below this zone there is a prominent blue fluorescent zone and several weak bluish and greenish zones. After derivatization under white light there are two prominent purple zones below the solvent front. A purple zone corresponding to osthole is detected and there may be a purple zone corresponding to imperatorin. Below this zone there are several yellow and purple zones. NOTE: the two samples of Doubleteeth pubescent Angelica root show variation.

Test for adulteration: Under UV 254 nm no blue fluorescent zone is seen at Rf ~ 0.57. Under UV 366 nm no blue fluorescent zone just below the position of imperatorin is seen. After derivatization under white light no zone is seen at Rf ~ 0.57 (black arrow) (Angelica root, Chinese Angelica root, Dahurian Angelica root, Lovage root, Chinese lovage root).

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  Doubleteeth Pubescent Angelica (root) HPTLC ID - UV 254 nm

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  Doubleteeth Pubescent Angelica (root) HPTLC ID - UV 366 nm

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  Doubleteeth Pubescent Angelica (root) HPTLC ID - Sulfuric acid, WRT

Source: HPTLC Association ^[2]