2. Experimental
2.1. Chemicals
All compounds and solvents employed were spectroscopic
grade commercial products and were used as received.
High molecular mass chitosan (H-Chit, acetylation degree = 22.8%,
Mw ∼ 1.34 × 106 in terms of repeating units) was purchased
from Fluka. The diacetylene monomer pentacosa-10,12-diynoic
acid (PCDA), purchased from Lancaster, was purified to remove
traces of spontaneously-formed polymer through dissolution in
ethanol followed by filtration with a 0.20 μm PTFE syringe filter.
All aqueous solutions were made with ultra-high-purity water,
twice distilled prior to use.