Development of photoresponsive self-assembled macrocycle supported on silica nanoparticles for controlled release of Ca2+

Abstract:

Mesoporous bioactive glass nanoparticles are an important class of therapeutics. Their action mechanism involves the release of vital ions such as Ca^2+,, which enhances remineralization of hard tissues. Bioglass surface modification has shown to improve the ion release; however, the regulated release process remains unachieved. Photoresponsive molecules are systems that display two different structural arrangements with different functions.

This lecture will discuss our designed model based on a noncovalent assembling of a visible-light active diarylethene carboxylate and guanidinium-doped bioactive glass support to establish a method for regulation of ions release.

Visible-light active diarylethene system was constructed by a careful introduction of p conjugation. HOMO-LUMO gap was reduced by the attachment of p conjugation at the parent thienyl ring. N-Heterocyclic moiety within the diarylethene framework allows controlled chelation/release of ions under light irradiation. The noncovalent self-assembly was generated by anion exchange with the positively charged guanidinium-doped bioglass. This novel material was spectroscopically characterized. Solid state NMR (²⁹Si, ¹³C), provided crucial information about the self-assembled molecular macrocyclic arrangement. Chelation/release activity was studied in aqueous medium.

Professor Fernando Arteaga Arteaga is from Mexico and holds a Ph.D. from the Osaka University supported by the MEXT scholarship. From September 2014 to May 2016, he conducted a more specialized research in The Institute of Microbial Chemistry, Tokyo, as a postdoctoral fellow. His research interest includes the development of novel synthetic methodologies mediated by Transition Metal Catalyst, and synthesis of heterocycles with potential biological activity. Prof. Arteaga received Poster presentation award at Hokuriku Seminar in Organic Synthesis. Kanazawa, Japan in 2013 and Poster presentation award at 15th Tetrahedron symposium. London, UK in 2014. In his free time, he enjoy hiking.