[Evaluation of inverse gas chromatography (IGC) methods to measure astragaloside solubility parameter from Buyang Huanwu decoction]

The solubility parameter determination of astrageloside from Buyang Huanwu decoction with inverse gas chromatography (IGC) method evaluation was investigated in this paper. Di-n-octyl phthalate Kwai alternative sample was used to carry out methodological study. The accuracy of the measured correlation coefficient was 0.992 1. Experimental precision measured by IGC experiments showed that the results were accurate and reliable. The sample was uniformly coated on the surface of an inert carrier and N2 gas was carrier gas, a variety of polar solvents such as isopropanol, toluene, acetone, chloroform, cyclohexane as probes. TCD detector temperature was 150 degrees C, gas room temperature was 120 degrees C. Similar headspace method was used whichever over 1 μL gas into the GC measurement, Retention time t(R), t(0) and all the parameters of air and probes molecules within the column were tested. Astragaloside solubility parameter was (21.02 ± 2.4) [J x cm(-3)] ½, literature value was 19.24 [J x cm(-3)] ½, and relevant coefficient was 0.984 5. IGC method is effective and accurate to measure ingredients solubility parameter.