In vitro protein (lysozyme) delivery studies in mesostructured bioceramics

• Main Author: Sim, Chiew Hoon.
• Other Authors: Loo Say Chye Joachim
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Materials::Biomaterials
• Online Access: http://hdl.handle.net/10356/15328
• Institution: Nanyang Technological University

Delivery systems for proteins in tissue engineering applications have some challenges. One of the most limiting factors of delivering biomolecules is their limited chemical and physical stability. In this report, mesoporous hydroxyapatite (MHA) and different compositions of bioactive glasses (MBGs) were prepared using nonionic block copolymer surfactants (F127) as structure-directing agent. Lysozyme Chloride crystalline (from egg white) was incorporated into MBGs and MHA by adsorption method in water and in vitro release of lysozyme from host was conducted in Phosphate Buffered Solution (PBS). In-vitro studies of proteins using MBGs and MHA as host were characterized using Fourier-transform infrared spectroscopy (FTIR), thermo-gravitmetric analysis (TGA), UV-vis spectroscopy and nitrogen adsorption analysis (BET equation). The varying of composition will affect the textural properties of MBGs. Generally with increasing silica contents there will be an increase in BET specific surface area with a decrease in pore size. Through the studies of delivery it can be observed that protein is loaded into MBGs and BG more efficiently than MHA and HA and that amount of proteins loaded was dependant on the BET surface area of the host. However the instability in the release profile had been examined that lysozyme may have denatured either in the process of loading or release. This indicates that lysozyme denatures in PBS even when releasing is conducted under room temperature. Hence, protein studies need to be further carried out to inspect its bioactivity of protein through high performance liquid chromatography (HPLC) for both loading and release in various parameters such as protein type and concentration of protein solution. In conclusion, more studies have to be done to determine whether MBG and MHA are suitable for tissue engineering applications especially in the aspect of release profile.