Gas chromatographic determination of ethylene oxide in materials for medical devices

Abstract

Residual ethylene oxide in materials for medical devices was determined by gas chromatography using hexane as an internal standard. Ethylene oxide in about 2 g sample of polyvinyl chloride tube which contains dioctyl phthalate was extracted with 10 ml of ethanol in a vial of 50 ml capacity at (20±5)°C for 24 h. The analytical conditions were as follows; column : stainless steel column (3 m×3 mm I.D.) packed with Chromosorb W-AW (80/100 mesh) coated with poly(propylene glycol succinate) (15 %), column temperature : 50 °C, injection temperature : 70 °C, detector : FID, internal standard : hexane. 10 μl of ethanol extract was injected. It took about 20 min for the chromatographic procedure. The corrected coefficient for the slope of calibration curve was 3.16. The precision of the present extraction method was comparable to that of the direct injection method of the present sample dissolved in dimethylformamide, but the latter method can not be applied to insoluble samples such as silicon, polyethylene and fluorocarbon resins. The coefficient of variation of the present method was about 3.5 % and the detection limit about 1 ppm.