Page 208 - Tandem Techniques

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It is seen that the signal-to-noise is still very high, so concentrations well below 125 µg per liter were
detectable. Between 10 and 100 µg per liter the standard deviation appeared to range from about 0.6 µg
per liter and 3.8 µg per liter respectively.

Figure 5.18.
Selected Ion Current Chromatograms of
4,4'-Methylenebis(2-chloroaniline) (ref 17)

Several years later Brunmark et al. [18} developed a similar procedure to monitor absorption of 4,4'-
methylene bisaniline from skin exposure by means of urine and blood plasma analysis. The urine
samples were treated in a very similar manner to Jedrzejczak and Gaind [17]. 2 ml of urine, 50 µl of
standard and 2 ml of 10 M NaOH were mixed and hydrolyzed at 80°C for 17 hours. The mixture was
then treated with 3 ml of toluene shaken for 10 minutes and centrifuged. A 1 ml sample of the organic
phase was treated with 20 µl of pentafluoro-propionic anhydride and shaken; the derivatization was
complete in 5 minutes. The reaction mixture was then treated with 2 ml 1.M phosphate buffer, shaken,
centrifuged and the organic layer was then used for GC/MS analysis.