[Fast determination of adenosine and cordycepin in Cordyceps and its deserted solid medium]

A fast analytical method for adenosine and cordycepin in Cordyceps and its deserted solid medium was developed by using a normal-phase cyan-group chromatographic column. The sample was extracted for 1.5 min using a microwave-assisted extraction system. The extraction was repeated twice. The analysis of adenosine and cordycepin was performed on an Eclipse XDB-CN column. The mobile phase was composed of methanol and water with a ratio of 7:93 (v/v) for isocratic elution. The detection wavelength was 260 nm. The composition and pH value of the mobile phase were investigated. The results showed that adenosine and cordycepin could be completely separated without matrix interference in 4.5 min. The linearity of the method was good with a linear correlation coefficient (r2) of 0. 999 8 for adenosine and 0.999 5 for cordycepin. The limits of quantification (LOQs, S/N = 10) of adenosine and cordycepin were 0.21 and 0.083 mg/L, respectively. The relative standard deviations (RSDs) of peak areas of six replicate injections were less than 2% both for intra-day and inter-day analysis. The average recoveries of adenosine and cordycepin ranged from 93.8% to 102.9% with the RSD not more than 3.62% (n = 5). The developed method is simple, fast, accurate and low-cost, and it can be used in the fast detection of adenosine and cordycepin in Cordyceps, carpohole, the deserted solid medium and its praeparatum.