2.2 Synthesis of Chitosan-PEG Nanocomposite
The chitosan-PEG nanocomposite was synthesized according to Liu and Kim
(Liu & Kim, 2012). Firstly, aqueous medium molecular weight chitosan
(Bio Basic) of 0.4% (w/v) was prepared in 2% (v/v) acetic acid
solution. Next, 0.1 g of PEG (Merck) and 0.1 g of phomopsidione were
added into the chitosan solution to obtain a Chitosan/PEG/Phomopsidione
(C/PEG/Ph) solution. Then, 3 mL of 0.4% genipin (Sigma) cross-linker
solution was added into the C/PEG/Ph solution. The final solution was
then homogenized for 30 min at room temperature using a homogenizer
(Heidolph Silent Crusher M) to allow proper mixing and bridging of the
polymeric components, then cast onto sterile Petri dishes. The hydrogels
were dried at room temperature for 48 hours. Lastly, the resulting
nanocomposite hydrogels were then stored at room temperature for further
experiments. Besides, a standard GC/PEG nanocomposite hydrogel was also
prepared as the negative control.