MIL-100 capsules coated with chitosan and cyclodextrin the biocompatible oral carriers

Abstract

Controlled drug release systems are part of a promising pharmaceutical segment, capable of providing greater stability for the drug and greater therapeutic efficacy, that can reduce adverse effects for treatments of various diseases such as cancer. However, most materials still present as main limitation the low capacity of large drug mass. To overcome this limitation, metal-organic frameworks (from English Metal Organic Frameworks - MOFs) are used as an alternative. MOFs are constituted by the coordinated link between metals and organic binders and form crystalline and highly porous materials. In order to improve the ability to incorporate large amounts of drug or even larger active molecules such as proteins, the development of hollow capsules from MOF has attracted much interest, by having a desirable properties for pharmaceutical application, such as mechanical resistance, stability and being pH-sensitive. The capsules of biocompatible metal-organic frameworks, such as MIL-100 (whose composition is iron and trimésic acid), are promising candidates for controlled drug release. In however, despite all these advantages, MOF particles aggregate and disrupt in a biological environment. An alternative to this problem would be to coat the nanoparticles to stability of this system, for example in gastrointestinal environment. Thus, this work aims to prepare a nanocarreador biocompatible based on MIL-100 capsules coated with chitosan polysaccharide and cyclodextrin. This method should not impair the structural properties and ability to release of the capsules. The interaction between chitosan and cyclodextrin with the capsules will be characterized by x-ray diffraction, infrared, dynamic light scattering (DLS), zeta potential and scanning electron microscopy. The results will contribute to the understanding of phenomena involved in surface modification of MOF capsules to perfect their properties as an drug carrier. This work is inserted into a broader general project supported by FAPESP in the modality of Regular Research Assistance (Process: 2017/21456-3).