rizvi

I'm having the hardest time figuring out the calculation for stock preparation. Can't figure out rather to use certified activity or certified purity in the calculation.Can anyone please help me to prepare stock of Vancomycin Standard (1mg/ml) from the following standardLink for COA of vancomycin standard is given below:https://www.sigmaaldrich.com/catalog/CertOfAnalysisPage.do?symbol=PHR1732&LotNo=LRAB3620&brandTest=SIAL&returnUrl=%2Fproduct%2FSIAL%2FPHR1732