Determination and Analysis of Toluene Diisocyanate Metabolites in Mice Using Gas Chromatography-Mass Spectrometry

This paper is to determine metabolites of toluene diisocyanate (TDI) in mice and deduced the pathway for toluene diisocyanate metabolism in the organism. Toluene diisocyanate was administered to mice for 2 weeks, samples of blood, feces, and urine were taken, and the structure of the toluene diisocyanate metabolites was determined using gas chromatography-mass spectrometry (GC-MS). Conditions for TDI chromatography: Supelco PTETM-5 chromatographic column (30 mm times 0.25 mm times 0.25 mum); initial column temperature: 90degC, which was maintained for 30 min, after which the temperature was increased at a rate of 40degC/min to 280degC, which temperature was then maintained for 5.25 min; temperature for the vaporizing chamber: 250degC; carrier gas: helium flowing at 1.0 mL/min. Conditions for chromatography of TDI metabolites in the organism: 94% methyl, 4% ethenyl-bonded-phase fused-silica capillary column (30 + 2 mX 0.25 + 0.02 mm); initial column temperature: 30degC, which was maintained for 5 min, after which the temperature was increased at a rate of 80degC/min to 280degC, which temperature was then maintained for 5 min; temperature for the vaporizing chamber: 250degC; carrier gas: helium flowing at 1.0 mL/min. Conditions for mass spectrometry: EI for ionization; 70 eV for ionization energy; 280degC for connecting tube temperature; 35-350 amu for range of scanning; and 1.0 muL for sample size. The results showed 2,4-toluene diisocyanate was metabolized into 2,4-diaminotoluene, which is completely the same in male and female animals. Under the conditions selected for GC-MS, TDI metabolites in the organism can be isolated. Endogenous impurities in the blood, feces, or urine of mice do not interfere with the measurements.