New hybrid materials capable to produce biodegradable scaffolds or films, targeted to tissue regeneration have gained increasing attention [1]. Among the various hybrid systems, some polymer-silica system has presented interesting results, namely as a stand-alone material for scaffolds [2,3]. Hybrid materials were developed by sol-gel processing, using polydimethylsiloxane (PDMS), gelatin, and poly(?-caprolactone) (PCL), as the organic domains, and borosilicate xerogels, as the inorganic one. Ions recognized for enhancing bioactivity, such as calcium, strontium and boron [4] were included in those inorganic domains. The chemical structures of the hybrid material were analysed by FTIR, 1H MAS (magical angle spinning), 29Si MAS, 29Si-{1H} CP-MAS (cross-polarization magical angle spinning) and 11B HAHN-ECHO NMR.
                                                                           
 
Acknowledgments
This work was developed within the scope of the project MULBIOIMPLANT (FCT Ref. POCI-01-0145-FEDER-032486), and by the project CICECO-Aveiro Institute of Materials, POCI-01–0145-FEDER-007679 (FCT Ref. UID/CTM/50011/ 2013), financed by national funds through the FCT/MEC and when appropriate cofinanced by FEDER under the PT2020 Partnership Agreement. This work was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MCTES (PIDDAC). The NMR spectrometers are part of the National NMR Network (PTNMR) and are partially supported by Infrastructure Project Nº 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC). This work is also financed by national funds through FCT-Fundação para a Ciência e Tecnologia, I.P., within the scope of the doctoral grant 2021.05864.BD.

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