Characterization and quantification of plastic additives in medical devices using online supercritical fluid...

Additives are essential to plastic materials, to obtain specific physico-chemical properties depending on intended applications. However, some of them are considered as toxic, such as bis(2-ethylhexyl)-phthalate (DEHP). This is a matter of concern, since plastic additives can migrate from plastic medical devices to contact matrices and then be harmful to patients. Therefore, extracting and analyzing compounds that can migrate from plastic materials is an essential step to evaluate the risk. The advantages of online supercritical fluid extraction and chromatography coupled to mass spectrometry (SFE-SFC-MS) were demonstrated previously, notably to avoid laboratory contamination. Here, this method is applied to the characterization of 24 plastic additives in medical devices used to infuse medical solutions to patients. The target compounds included plasticizers (phthalates and non-phthalates) such as DEHP or its substitutes (like TOTM, ATBC, DEHA, DINCH), antioxidants (Irganox 1076, Irganox PS800) and lubricants (erucamide and oleamide). First, the polymers were characterized using Fourier-Transform Infrared spectroscopy (FTIR). Then, plastic additives were characterized with SFE-SFC-MS. The proportion of DEHP and its substitutes varied greatly from one sample to another, depending on the plastic material nature, and its manufacturing date. Furthermore, the method was validated for DEHP using accuracy profiles. The validated method allowed quantifying DEHP from 5 to 35 ng, with average RSD values of 9% and 15% obtained for the calibration and validation series respectively. Finally, the greenness of the method was favorably evaluated with AGREEprep green score (0.74), especially when compared to traditional extraction methods used for plastic additives.