2.1　Instrumentation

A UV-2450 spectrophotometer(Shimadzu，Japan)and Prominence UFLC20A(Shimadzu，Japan)high-performance liquid chromatograph(HPLC)equipped with a reversed-phase column(C18 column，4.6mm×150mm)and ultraviolet detector was employed.Infrared spectroscopy(IR)was performed in potassium bromide plates using a FTIR-8400S infrared spectrophotometer(Shimadzu，Japan).Scanning electron micrographs(SEM)of polymers were obtained on an EVO MA25 instrument(Zeiss，Germany).(https://www.daowen.com)

The concentration of cordycepin was determined by HPLC.Methanol-water(85∶15，v/v)was used as mobile phase at a flow rate of 1.0mL/min.The detection wavelength was 260 nm，the sample volume was 10μL，and column temperature was 35℃.Standards of 27.1μg/mL，54.2μg/mL，81.3μg/mL，108.4μg/mL，and 162.6μg/mL cordycepin were prepared.A calibration curve was plotted using the peak areas as the ordinate and cordycepin concentrations as the abscissa，and the linear regression relationship was Y=1.4757×10—5 X with a correlation coefficient was R2=0.9998.