IADR Abstract Archives
Synthesizing Novel pH-Sensitive Zwitterionic Monomers for Dental Applications
Objectives: pH-sensitive zwitterionic monomers change their charge status in response to pH change. Considering the dramatic pH change during the development of dental caries, these monomers might find their applications in fighting dental caries. The aim of this study is to synthesize and evaluate several sulfonamide-based pH-sensitive zwitterionic monomers for dental applications.
Methods: Monomers were synthesized via two-step reactions. Each Intermediate and final monomer were purified via crystallization. Their chemical structures and purities were characterized via 1H-NMR, MS and UV coupled to UPLC. Several resin formulations were prepared by mixing Bis-GMA and TEGDMA with QC, DPIHP and EDMAB as the photo-initiators and catalyst, respectively, without (as base formulations) or with (experimental formulation) one of the monomers. Each formulation (75 µL) was added to a silicon mold (6 mm in diameter) and exposed to the Valo curing light (3200 mW/cm2) for 3 x 3 seconds to form resin discs. The cytotoxicity of each type of disc was evaluated using human primary gingival epithelial cells (from Dr. George Huang’s lab) via the MTT assay.
Results: 1H-NMR and MS spectra confirmed the successful synthesis of each monomer. UV spectra further confirmed the high purity of these monomers (>95%). Resin composite discs were successfully prepared for each formulation prepared. MTT assay revealed that cells maintained good viability after being exposed to each type of disc foe 20 hours.
Conclusions: Sulfonamide-based pH-sensitive zwitterionic monomers were successfully synthesized. These monomers could be mixed into base formulation to form resin composite after being exposed to UV curing light. The prepared resin composite discs are comparable to the disc formed using base formulations in terms of cytotoxicity. These results warrant further evaluation for these monomers.
Methods: Monomers were synthesized via two-step reactions. Each Intermediate and final monomer were purified via crystallization. Their chemical structures and purities were characterized via 1H-NMR, MS and UV coupled to UPLC. Several resin formulations were prepared by mixing Bis-GMA and TEGDMA with QC, DPIHP and EDMAB as the photo-initiators and catalyst, respectively, without (as base formulations) or with (experimental formulation) one of the monomers. Each formulation (75 µL) was added to a silicon mold (6 mm in diameter) and exposed to the Valo curing light (3200 mW/cm2) for 3 x 3 seconds to form resin discs. The cytotoxicity of each type of disc was evaluated using human primary gingival epithelial cells (from Dr. George Huang’s lab) via the MTT assay.
Results: 1H-NMR and MS spectra confirmed the successful synthesis of each monomer. UV spectra further confirmed the high purity of these monomers (>95%). Resin composite discs were successfully prepared for each formulation prepared. MTT assay revealed that cells maintained good viability after being exposed to each type of disc foe 20 hours.
Conclusions: Sulfonamide-based pH-sensitive zwitterionic monomers were successfully synthesized. These monomers could be mixed into base formulation to form resin composite after being exposed to UV curing light. The prepared resin composite discs are comparable to the disc formed using base formulations in terms of cytotoxicity. These results warrant further evaluation for these monomers.