Initial studies on the penetration of spirohydantoin mustard into the cerebrospinal fluid of dogs.

A gas-chromatographic-mass-spectrometric method using selected ion monitoring has been developed to detect and quantitate levels of spirohydantoin mustard (SHM) as low as 1 ng per injected sample. The ions chosen for analysis of the drug were at m/e 154, 156, and 299. Using this procedure, the distribution of SHM in the blood and cerebrospinal fluid (CSF) of dogs following intravenous administration has been studied. The initial blood decay of SHM is rapid with a half-life of 1.78 and 1.85 min for 2 different dogs. SHM enters the CSF and, after reaching a peak value at approximately 10 min, exhibits a decay curve similar to that found in blood.