we are analysing various ganoderic acids in Ganoderma Mushroom. What is the best labelled standard that i can use to calculate the recovery and EE of my method.
Instead of a labelled compound use Hydrocortisone as a standard; this method was validated by Yongli Liu, Youping Liu, Feng Qiu, Xin Di, "Sensitive and selective liquid chromatography–tandem mass spectrometry method for the determination of five ganoderic acids in Ganoderma lucidum and its related species" Journal of Pharmaceutical and Biomedical Analysis 54 (2011) 717–721.
I couldn't locate a source for any heavy isotope labeled Ganoderic Acids through Scifinder or Chemexper. The best internal standard would be a heavy isotope labeled version of each Ganoderic Acid, the ones to purchase (or synthesize) are the lowest priced ones available that will work for your application.