Analytical Method and Detection Limit Studies for Detection of GB in GB Hydrolysate

摘要

The work presented here describes the applicability of an extraction/GC/MS anaiyticai method for detection of GB in caustic matrices. The method was designed to minimize GB reformation and spiked GB degradation during workup and analysis. Extractions were performed at pH 9 and 4 deg. C, using methylene chloride as the solvent. The extraction ratio was 15 mL matrix to 1.5 mL solvent. The GC/MSD in the SIM mode was used for analysis. The method was tested using two distinctly different sources of GB, one containing only TBA as stabilizer, and the other containing TBA and DICDI as stabilizers. Method detection limits (MDL) obtained for NaOH hydrolysate matrices produced from these sources were 4.5 ng/mL (ppb) and 8.4 ng/mL, respectively. The GB spike recoveries were 82.4 and 75.2%, respectively. No GB reformation was observed in the TBA-stabilized unspiked hydrolysate. The GB was detected, presumably via reformation during analysis, in the TBA/DICDI-stabilized unspiked hydrolysate, but was below the MDL.