National Institute for Occupational Safety and Health

“ Prepare a calibration graph (peak area vs. mass of Aspartame, μg per sample) . Determine the recovery at least once for each lot of filters used for sampling in the range of interest. Prepare six filters at each of three levels plus three media blanks. a. Add known amounts of Aspartame in methanol to the filters. b. Cover filters. Allow to stand overnight for solvent evaporation. c. Prepare samples (step 5 through 7) , and analyze (step 11 through 13) together with standards. d. Determine recovery (R) . Construct a graph of R vs. μg Aspartame recovered. ”

“ Calibration stock solution: 5 mg/mL. Add 0.05 g Aspartame and dilute with 10 mL eluent B.
1. Sampler: 1-μm, 37-mm PTFE filter (Millipore FALP or equivalent) with a cellulose backup pad in a 37-mm polystyrene 2-piece cassette. 2. Personal sampling pump capable of 1 to 3 L/min, with flexible connecting tubing. 3. High-performance liquid chromatograph (HPLC) with UV detector, 220-nm, integrator and C 18 column (page 5031-1) . 4. Syringe filters, 13-mm: 0.45 μm, PTFE. 5. Syringe, 10-mL, disposable. 6. Vials, glass, scintillation, 20-mL with PTFE-lined caps. 7. ”