Chemical Core Analysis Procedure

Urine and serum samples were transferred to the Chemical Core Analysis Facility of the Occupational and Environmental Health Sciences Institute (EOHSI), Rutgers University. ZEA and its metabolites were measured using an HPLC-MS-MS technique. 0.25 mL sodium acetate buffer (pH=4.65) and 10 μL of β-glucuronidase from Helix pomatia were added into 1mL of urine or serum sample. The enzymatic deconjugation was conducted in a water bath at 37 °C overnight. Then liquid-liquid extraction was performed on a Visiprep™ DL SPE vacuum manifold to isolate analytes from urine or serum. Chem Elute 1mL cartridge was used in the liquid-liquid extraction. The injection volume was 20 µL. A Thermo LTQ mass spectrometer was interfaced to a Finnigan Surveyor Autosampler …show more content…
Meat samples (n=5) included: ground beef, and grass fed ground beef, store-prepared burger patty meat, 98% ground turkey, and rib eye steak. Grain samples (n=26) included: bulgur, couscous, wheat berries, oats, rye berries, brown flax, pearl quinoa, red quinoa, millet, buckwheat, amaranth, while popcorn, yellow popcorn, farro, barley, spelt, brown rice, cornstarch, corn meal, corn flakes, chia, multigrain cereal, corn grits, sorghum, teff, multigrain infant cereal. Milk samples (n=5) included: cow’s milk (fat free, low fat (1%), reduced fat (2%), and whole milk), and goat’s milk. Samples of livestock feed used for cows and pigs on a Rutgers University farm were also analyzed and include: heifer feed, sow gestational feed, pig grower feed, pig creep feed, pig lactation feed. (See online supplemental material). Specific protocols to prepare each food item were followed, as per R-BioPharm’s assay