Walters-Thompson K M, Mason W D
Pharmacokinetics Laboratory, University of Missouri-Kansas City, School of Pharmacy 64108.
Pharm Res. 1992 Jul;9(7):929-32. doi: 10.1023/a:1015861218342.
An HPLC/GC-MSD method for the determination of diphenhydramine in rabbit whole blood has been developed and validated. This method is based on a liquid-liquid extraction and reversed-phase chromatography with ultraviolet absorbance detection monitored at 258 nm. HPLC eluant fractions containing diphenhydramine and the internal standard, orphenadrine, were collected, reextracted, then subjected to GC-MSD analysis. Whole blood was utilized, thereby decreasing the required sample volume and increasing the sensitivity of the assay. Diphenhydramine concentrations can be quantitated over a range of 1 to 1000 ng/ml whole blood.