The MicroGram Phosphatidylcholine Assay Kit (Catalog number: MPC200K) is for measurement of L-α-phosphatidylcholine (PC) at concentrations of 0.005% (0.05 mg/ml) or higher.  The assay is based on the principle that phosphatidylcholine interacts with the MPC reagent and enhances the fluorescence intensity at 535 nm (excitation at 485 nm).  L-α-phosphatidylglycerol (PG) does not interact with the MPC reagent. 

The assay is compatible with most biochemical assay buffers such as HEPES or Tris-HCl buffers. It is compatible with low concentrations of Ethanol and DMSO.  It is not compatible with phosphate buffers.  If ATP is used for the biochemical reaction, it is recommended to use ATP concentrations below 200 µM.  The assay is not compatible with most detergents.