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Title: Analysis of the extractive and hydrolytic behavior of microthane poly(ester-urethane) foam by high pressure liquid chromatography

Journal Article · · Journal of Biomedical Materials Research; (United States)
; ; ;  [1]
  1. ConvaTec, Skillman, NJ (United States)

Microthane foam, a poly(ester-urethane) (PU) used in the manufacture of Meme/Replicon breast implants, was analyzed by an HPL method to determine whether 2,4- and 2,6-toluenediamine (TDA) were formed under a variety of physiological and nonphysiological extraction and hydrolytic conditions. At the detection limit of 20 ppb, no 2,4- or 2,6-TDA was observed in either methyl tert-butyl ether (MTBE), or aqueous buffer extracts of PU foam. The predominant extractable components identified by HPLC UV-analysis, were a mixture of nonaromatic and aromatic PU fragments. Moreover, no detectable amounts of TDA were found in foam or MTBE extract of foam incubated in phosphate buffer, pH 7.4, at 37 C for 5 days. By contrast, 2,4- and 2,6-TDA were found in foam and foam extracts exposed to low concentrations of either strong mineral acid or base; higher levels were found at higher acidity, treatment temperature, or durations of incubation. Moreover, 2,4- and 2,6-TDA were found in oligomers isolated by preparative HPLC and exposed to alkaline conditions. Finally, 1-2 ppm of 2,4-TDA was detected when PU foam extracts were prepared by the Snyder-Breder method, which employs acidic and alkaline conditions in the work-up procedure. Based on these findings, the authors suggest that published observations of 2,4-TDA formation from in vitro and ex vivo extractions of PU foam are artifacts resulting from pH effects on oligomeric PU fragments present in or extracted from the foam.

OSTI ID:
6773720
Journal Information:
Journal of Biomedical Materials Research; (United States), Vol. 27:5; ISSN 0021-9304
Country of Publication:
United States
Language:
English