title: Residual ethylene oxide determination in polymethyl methacrylate disks and intraocular lenses by headspace gas analysis and N,N-dimethylformamide extraction.
abstract: The residue in an ethylene oxide (EO)-exposed polymethyl methacrylate (PMMA) material [flat disk and intraocular lens (IOL)] was determined using three methods: semiautomatic and manual headspace methods and N,N-dimethylformamide (DMF) solvent extraction. Results from the analysis of three different sample configurations at three different EO concentrations are compared. Results from the DMF extraction of PMMA indicate that the headspace methods at 100 degrees C are not exhaustive with respect to recovery of total residual ethylene oxide. Furthermore, the manual headspace method appears to be slightly more effective than the semiautomatic injection headspace method. Sorption of EO and subsequent extraction is related to the surface area-to-volume ratio of the sample, with higher concentrations observed in samples with the high ratio.
authors.affiliation: Food and Drug Administration, Center for Devices and Radiological Health, Rockville, MD 20852.
authors.forename: N T
authors.initials: NT
authors.lastname: Lao
authors.forename: R R
authors.initials: RR
authors.lastname: Rajan
authors.forename: H F
authors.initials: HF
authors.lastname: Bushar
mesh_terms: D001322:Autoanalysis; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002849:Chromatography, Gas; D004126:Dimethylformamide; D004350:Drug Residues / Q000032:analysis; D005027:Ethylene Oxide / Q000032:analysis*; D007910:Lenses, Intraocular; D008768:Methylmethacrylates / Q000032:analysis
chemical_list: D008768:Methylmethacrylates; D004126:Dimethylformamide; D005027:Ethylene Oxide