[Determination of adenosine and cordycepin in Cordyceps sinensis and C. militarris with HPLC-ESI-MS].

Objective: HPLC-ESI-MS to establish a method for simultaneous determination of adenosine and cordycepin in Cordyceps sinensis and C. militarris.
Method: HPLC-ESI-MS method. An electrospray ionization (ESI) interface and selective ion monitoring (SIM) mode were used. The analytical column was a 2.0 mm x 150 mm Shimadzu VP - ODS column and the mobile phase was water (94%), methanol (5%) and formic acid (1%). 2-Chloroadenosine was used as internal standard for this assay.
Result: The regression equations and coefficient were Y = 0.134 6X + 0.001 29 (r = 0.998 4) for adenosine, Y = 0.216 4X + 0.021 5 (r = 0.999 1) for cordycepin. The liner range was 0.5 approximately 124.5 microg x mL(-1) and 0.5 approximately 136.5 microg x mL(-1) for adenosine and cordycepin, respectively. The average recoveries of adenosine and cordycepin were 95.8% and 98.1%, respectively.
Conclusion: This method is highly sensitive, fast and selective, which can be used for the determination of nucleosides in C. sinensis and its substitutes. This method can also be applied for the quality control of above herbs.