Identification of Phthalate Esters Using the SMCI Method

Phthalate esters are used as plasticizers, and contamination by contact with food is a concern. Because phthalic acid is structurally toxic, precise qualitative analysis is required. However, since the basic skeleton is common and a similar mass spectrum is obtained by the EI method, it is necessary to confirm the molecular weight for qualitative analysis.
In this study, we confirmed the pseudomolecular ion of phthalic acid by using the SMCI method. Since the SMCI method does not require combustible gas such as methane, the qualitative analysis of phthalic acid can be performed even by customers who have difficulty in installing the same gas.