Amphiphilic CCMCs were synthesized under mild conditions and their chemical structures were characterized by FT-IR and 1H NMR spectroscopy. Fluorescence analysis showed that CCMCs could self-associate to form polymeric micelles in aqueous solution. IND was encapsulated during the formation of CCMC micelles and its in vitro release properties were investigated. The loading capacity was more than 50% and the loaded IND was slowly and steadily released into the medium over a period of 8 h. The CCMC micelles showed pH-responsive behavior during the drug-loading and release processes. CCMC is promising as a potential delivery system for the controlled release of IND with a pH-responsive property.

The self-assembly of amphiphilic cholesteryl-bearing carboxymethylcellulose derivatives (CCMCs) from individual molecules to self-aggregates, in addition to their rheological behaviour in aqueous solution were investigated. The conformations of the individual CCMC individual molecules and self-aggregates, and the microstructures of CCMC self-aggregates were characterized using the static and dynamic light scattering analyses, and the steady fluorescence technology. The results showed that the individual CCMC chains became compact, and aqueous NaCl solution changed from an approximate h solvent to a bad one when the number of hydrophobic cholesteryl groups increased. The CCMC self-aggregates exhibited as compact spheres. The microstructural characterization indicated that one CCMC self-aggregate consisted of multiple individual CCMC molecules and hydrophobic microdomains, and multiple cholesteryl groups selfassociated into one hydrophobic microdomain. The atomic force microscopy images of CCMC selfaggregates in phase mode showed that the multiple interior hydrophobic phase separation regions were surrounded by hydrophilic polysaccharide chains, providing an evidence for multiple hydrophobic microdomains in one self-aggregate. The rheological analysis proved that the CCMC self-aggregates were a microgel, in which the associations of cholesteryl groups provided multiple cross-linking points in the polymer network. The microgel solutions displayed a unique thixotropy and a shear thinning behaviour.