Determination of ϵ‐caprolactam migration from polyamide plastics: a new approach

A new gas chromatography method for determination of ϵ‐caprolactam (CPR) migration from packaging materials such as: polyamide (PA) films, PA granulates, PA/PE (polyethylene) laminates, PA casings, etc., to food simulants has been developed. Water, 3% w/v acetic acid, 15% and 95% v/v ethanol and olive oil have been used as a food simulants. Using the 1,4‐butanediol (BUG) as an internal standard (instead of aza‐2‐cyclononanone), calibration curves were constructed. Very good separation of CPR from BUG was achieved by using a Nukol fused silica capillary column (Supelco), 25 m × 0.32 mm. The time of analysis is shorter than 12 min: 7.69 min for BUG and 11.60 min for CPR. The regression line equation for CPR migration to water is: y  = 0.080 x  + 0.14; to olive oil: y  = 0.010 x . The sensitivity of the developed method is appropriate for the quantitative determination of CPR in an analyte concentration of approximately 0.2 mg/kg, when the specific migration limit (SML) for this compound, according to Directive 90/128/EEC, is 15 mg/kg food simulant. Copyright © 2001 John Wiley & Sons, Ltd.