Needle Trap Device Used for Headspace Sampling

Workers at the University of Waterloo (Waterloo, Ontario, Canada) combined a needle trap device and a dynamic headspace method to sample an aqueous BTEX (benzene, toluene, ethylbenzene, and p-xylene) mixture. The device consisted of a 22-gauge stainless steel needle filled with divinylbenzene particles. A sequential purge-and-trap approach using a syringe pump followed the sampling step. The researchers obtained 1-ng/mL detection limits for BTEX using the technique.