(408c) Computer-Aided Molecular Design of Water Compatible Visible Light Photosensitizer for Dental Applications

Dental adhesive undergoes phase separation into hydrophobic and hydrophilic-rich phases during infiltration through the demineralized dentin. Previous investigations have exhibited that the hydrophilic-rich phase is poor in the dimethacrylate component (crosslinker) and photoinitiators which are hydrophobic in nature. Thus the hydrophilic-rich phase undergoes poor polymerization and crosslinking, which creates a vulnerable region prone to failure. The objective of this study is to design a water compatible visible light photosensitizer by computer-aided molecular design. Quantitative structure property relationships (QSPRs) were developed for target properties which were octanol/water partition coefficient, photon absorption efficiency (PAE) and molar extinction coefficient (ξ). The correlations were built using molecular descriptors for specific model building set of photosensitize molecules. The correlations are capable of accurately predicting the target properties. The QSPRs along with structural constraints were used to construct a combinatorial optimization problem which represented a mixed integer non-linear problem (MINLP). The MINLP was then solved to near optimality via a stochastic method, Tabu Search. This study proposed potential candidate photosensitizer molecules which will be hydrophilic in nature and possess absorption properties suitable for use in dental adhesive system.

Key words:dental adhesive, photosensitizer, hydrophilic, QSPRs, molecular descriptors, computer-aided molecular design

** This investigation was supported by the Research Grant: R01 DE022054 from the National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD  20892.