Fig 2.

(A) Typical graph showing absorption spectra of RB and CSRB. The absorption peak at 549 nm of RB shifted to 560 nm and became broader following conjugation with chitosan. (B) Ratio of monomer (560-nm) to dimer (528-nm) peak decreased linearly with increase in the concentration of CSRB (R² = 0.95) in the solution, suggesting aggregation/dimerization. (C) FTIR spectra of chitosan and CSRB (400 to 4,000 cm⁻¹ wave number).