دانلود رایگان مقاله سنتز و شناسایی آمیلوز استیله شده و توسعه گنجایش مجموعه با ریفامپین

ABSTRACT

Amylose (AM) tends to form single helical inclusion complexes with suitable agents. These complexes are considered promising biomaterial carrier since the guest molecules can be released later, leading to many applications, especially in the pharmaceutical industry. Rifampicin (RIF) has long been recognized as an active drug against Mycobacterium tuberculosis, however, the administration of RIF in high dosages can originate unwanted side-effects. Due to the fact that the use of native amylose (AM) in the formation of complexes is limited by their low water solubility, it was acetylated with a medium degree of substitution (DS), allowing solubilizing (0.5 gL−1) acetylated amylose (AMA) in water at neutral pH, in opposition to that observed with native amylose (trace solubility). The resulting acetylated amylose was characterized by means of Fourier Transform Infrared (FT-IR) spectroscopy and Scanning Electron Microscopy (SEM). FT-IR results indicated that the acetylation of anhydroglucose units of amylose corresponds to a low DS, whereas SEM results suggested that the smooth surfaces of amylose granules were changed into rougher surfaces after acetylation. Ultraviolet absorption spectroscopy (UV–vis) analysis confirmed the formation and allowed the quantification of both native (AM-RIF) and acetylated (AMA-RIF) amylose inclusion complexes. Their characterization in solution was performed by dynamic light scattering (DLS) and zeta potential (ZP) measurements. The average size of inclusion complexes as determined by DLS, ranged between 70 and 100 nm. Besides, ZP analysis showed that both complexes are more stable in the presence of RIF. This study may lead to the development of an effective method for the preparation of amylose inclusion complexes, which is beneficial to their further application in drug delivery systems.

4. Conclusions

In conclusion, acetyl groups were introduced into the structure of amylose, which was confirmed by FT-IR. SEM data indicated that the amylose surface was modified and their surface became rougher after acetylation. The results of UV spectroscopy, DLS and ZP analysis confirmed the formation of the AM-RIF and AMA-RIF inclusion complexes. The results demonstrated that it is possible to develop inclusion complexes of RIF with AM and AMA with moderate efficiency. Finally, the complexes formed have adequate size for in vivo applications, and the lower ZP values are important for complexes to have longer blood circulation time and be more accessible for the attachmentin the epithelial cell surface, which increase their uptake. Thus, this study may lead to the development of an effective and innovative method of drug delivery through inclusion of RIF in amylose complexes and eventual use against tuberculosis.