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Existing Methods
•
HPTLC
–
Lobo
et al
., A HPTLC densitometric method for the determination
of aloeverose in
Aloe vera
gel.
Fitoterapia
2010
,
81,
231–233.
HPTLC conditions:
Plate: Si-gel Si60F
254
Developing: n-butanol: n-propanol:
l i l
ti
id t
aloeverose
g ac a ace c ac : wa er
(30:10:10:10 v/v/v/v).
Reagents: anisaldehyde sulphuric
acid reagent; heating the plate at
105–110°C for 5min.
Fig.
HPTLC chromatogram of
A. vera
gel
(from the above paper).
Existing Methods
•
Colorimetric Assay by Red Dye – Congo Red
–
Eberendu
et al
., Quantitative Colorimetric Analysis of Aloe
Polysaccharides as a Measure of
Aloe Vera
Quality in Commercial
Products.
J. AOAC International
,
2005
,
88
, 684‐691.
N
S
N
N
NH
3
O
O O
O
-
Na
+
•
Complex of Congo red with polysaccharides and assayed
at 540nm
+
Aloe polysaccharides
Congo red dye
N
H
2
N
S
O
-
Na
+
O