Dual-modified starch micelles as a promising nanocarrier for doxorubicin.

Natural amphiphilic polymer micelles have garnered considerable research attention as nanocarriers for delivering drugs. The objective of this study was to explore the possibility of applying biocompatible dual-modified starch micelles as drug delivery vehicles. To this end, a dual-modified corn starch polymer (SCD) was synthesized with zwitterionic sulfobetaine and deoxycholic acid; spherical micelles with an average particle size of ~200 nm were prepared through the self-assembly of SCD. The effects of dual modification on the degree of substitution, molecular structure, and functional properties of SCD were investigated. Further, doxorubicin was successfully incorporated into the micelles, and an in vitro drug release study was performed to confirm that the drug-loaded micelles displayed pH-sensitive properties with controlled and sustained release. The dissolve-diffuse-erosion-degradation release process was described according to the dynamic models of drug release for SCD micelles. The results can be used as reference information for further studies in the biotechnology and pharmaceutical domains.

Structure and properties of corn starch synthesized by using sulfobetaine and deoxycholic acid.

Novel starch polymers (sulfobetaine-starch-deoxycholic acid) were first synthesized by grafting zwitterionic sulfobetaine and deoxycholic acid onto corn starch molecules. In order to explore the mechanism of modified starch, the chemical structure, morphological properties, thermal stability, and self-assembly performance of modified corn starch were determined. Preliminary structural characterization, using NMR, demonstrated that the glucose carbon C6 was the main etherification grafting site and C2 and C3 were the esterification grafting sites. This was confirmed using FT-IR to detect the presence of a new carbonyl signal around 1739 cm-1. XRD, SEM, and PLM micrographs showed structural losses in the starch granule. Thermogravimetric analysis showed an increase in thermal stability with etherification and esterification in nature. Self-assembly performance analysis demonstrated that the polymer formed more thermodynamically stable micelles under highly diluted conditions. This work will help expand the space for starch application.