On the Structural Analysis and Electronic Properties of Chitosan/Hydroxyapatite Interaction

The interaction between chitosan and hydroxyapatite is discussed in terms the electronic properties using semiempirical PM5 quantum mechanical method. Furthermore, B3LYP/3-21G** model shows comparable vibrational frequencies as compared with FTIR frequencies. Chitosan interacts physically through its hydrogen bonding with OH-, Ca2+ and PO43- of hydroxyapatite. Electronic properties indicate that no charge transfer and no ionization as a result of the proposed interactions. However a decrease in HOMO/LUMO took place corresponding to chitosan/hydroxyapatite interactions. The present modeling work postulate that stable blends are obtained in terms the calculated thermodynamic parameters. The increased total dipole moment and decreased band gap energies dedicate these blends for many biological applications; where their interaction with the surrounding biological system is needed with minimal change in the chemical and/or electrical properties to ensure biocomptability.