Thermal Extraction: An Alternative Headspace GC–MS Method for Volatile Extractables from Medical Device Materials

Volatile extractables such as monomers, additives, processing aids, material impurities, byproducts, and residual solvents in medical devices, released from materials during use, are a potential safety concern. Identification and quantification of volatiles released from medical devices is challenging due to the absence of qualified standard methods for the analysis. In this study, a solventless thermal extraction gas chromatography/mass spectrometry (TE-HS-GC–MS) analysis method was developed to identify and quantify volatile extractables from medical device materials. Instrument parameters and sample extraction conditions (equilibration time and temperature) were optimized with an acrylonitrile butadiene styrene (ABS), a BUNA rubber-positive control, and a high-density polyethylene (HDPE)-negative control and tested with five representative medical devices or device parts. External calibration curves generated with commonly found volatiles produced a limit of quantification (LOQ) as low as 4 ng with a linear dynamic range from 4 to 128 ng (acrylonitrile). Thermally extracted volatiles from medical device materials were compared with those from saline extraction (SE) to evaluate the suitability of the solventless TE-HS-GC–MS analysis method relative to commonly-used solvent extraction practices. Results showed that the optimized solventless TE-HS-GC–MS method, compared to the SE method, provided a 40–116% higher number of identifications. Increasing equilibration time with TE increased the number of identifications and peak area of the compounds. Several toxicologically relevant volatiles were identified in the device extracts. Overall, the optimized solventless TE-HS-GC–MS method is more effective than the SE method in identifying volatiles in medical devices/materials, while reducing the sample preparation burden and the extraction time significantly.