Determination of Residual Methylmethacrylate Monomerin Denture Base Resins by Gas Chromatography

Acrylic base resins are widely used in orthopedics and dental surgery. It is generally accepted that due to the incomplete conversion of methyl methacrylate (MMA) monomer to the polymer form during polymerization of the resin, some MMA monomers remain in the hardened material. MMA monomer has been reported to cause abnormalities or lesions in several organs of animals. Study of the literatures showed that there are no perfect and valid methods for analysis of MMA. The aim of this study was to develop a simple and valid method for determination of MMA residual monomer in the denture base resins.

We have developed and validated an analytical procedure employing gas chromatography with flame ionization detector (GC-FID), with temperature programming, and a close analogue internal standard for fast and repeatable analysis of MMA residual monomer contents in denture base polymers. For quantification of monomer, two calibration curves were used by two different methods of solution preparation and they were compared to each other. The assay was linear over the range of 0.03-0.6 mg/ml MMA with correlation coefficients (r²) of greater than 0.99. Accuracy, intra-day (Error<9.1%) and inter-day (Error<6.6%) , precision (RSD<5.5% and RSD<6.5%, respectively) were in acceptable values over the examined concentration range. Limit of detection (LOD) and limit of Quantification (LOQ) for MMA were 0.01 and 0.02 mg/ml, respectively. In conclusion, the proposed method was a simple and fast assay for MMA residual monomer in denture base resins.