This study indicates that supercritical fluid extraction ( SFE ) can
be adopted jnstead of traditional solvent
extraction to extract
the active constituent indirubin in Chinese medicinal
materials(
Strobilanthes cusia,Isatis tinctoria and Polygonum
tinctorium).A two-level , two- factor(22) factotial design approach
is used to optimize the
temperature and pressure in SFE.A systematic
method is also used to optimize five variables(temperature ,
pressure , modifier concentration , static extracting time and CO2
dynamic extracting volume)of SFE. The results demonstrate the utility
and efficiency of factorial design in two-level ,
two-factor(22)for optimizing SFE temperature and pressure , and also
show faster extraction kinetics and the ability of SFE to vary the
extracting power through adjustments of the above five
variables.Sample extracts were analyzed bymicrobore high performance
liquid chromatography(MHPLC).The method showed good
linearity(r=0.9998,n=5)in the range of 2.11～10.57 μg·ml-1 of
indirubin.The average recovery was 94. 63%with RSD<0. 92%(n=4). MHPLC
condition : column : Spherisorb 3μm,C18( 1 mm × 1 5 0 mm);mobile
phase : methanol-water(7:3);flow rate : 40μl·min-1;UV detection :
290 nm;recorder sensitivity: 0. 01 AUFS; injection volume : 0.1μl.