Fig. 3. (A) Fourier Transform Infra-Red (FTIR) spectra of BRB–NPs, free BRB, P407, shellac ammonium salt (free shellac), and Shellac NPs; (B) UV-vis absorption spectrum of BRB, free shellac, non-coated BRB-loaded shellac NPs and P407; (C) the encapsulation efficiency percentage of different concentrations of BRB-loaded shellac NPs at pH 5, and (D) the percentage of in vitro BRB release as a function of time at different pH.