Aqueous sorption of tetracycline using rarasaponin-modified nanocrystalline cellulose

The sorption ability of NCC and its modified form against tetracycline were investigated. NCC modification was carried out using a natural surfactant, namely rarasaponin, to improve the NCC adsorption capacity. The modification was made with a mass ratio of NCC to rarasaponin 10:1 (10N1R) and 20:1 (20N1R). The modified NCC characteristics were investigated using Fourier transform infrared (FTIR), zeta potential analyzer, X-ray diffraction (XRD), and scanning electron microscope (SEM). There are no structural changes to the surfactantmodified NCC, as revealed by SEM. However, other characterizations show that the incorporation of rarasaponin indeed altered some characteristics of NCC. The modified NCC shows higher adsorption capacity towards TET. The adsorption capacity of TET was 13.97, 16.47, and 18.11 mg/g (at 60 °C) for NCC, 10N1R, and 20N1R, respectively. The kinetic release (desorption) study of TET@20N1R showed a release efficiency of 18.28% at pH 3 and 55.49% at pH 7