*Article* **Production, Characterization and Biocompatibility Evaluation of Collagen Membranes Derived from Marine Sponge** *Chondrosia reniformis* **Nardo, 1847**

**Marina Pozzolini 1,\*, Sonia Scarfì 1, Lorenzo Gallus 1, Maila Castellano 2, Silvia Vicini 2, Katia Cortese 3, Maria Cristina Gagliani 3, Marco Bertolino 1, Gabriele Costa <sup>1</sup> and Marco Giovine <sup>1</sup>**


Received: 12 March 2018; Accepted: 27 March 2018; Published: 29 March 2018

**Abstract:** Collagen is involved in the formation of complex fibrillar networks, providing the structural integrity of tissues. Its low immunogenicity and mechanical properties make this molecule a biomaterial that is extremely suitable for tissue engineering and regenerative medicine (TERM) strategies in human health issues. Here, for the first time, we performed a thorough screening of four different methods to obtain sponge collagenous fibrillar suspensions (FSs) from *C. reniformis* demosponge, which were then chemically, physically, and biologically characterized, in terms of protein, collagen, and glycosaminoglycans content, viscous properties, biocompatibility, and antioxidant activity. These four FSs were then tested for their capability to generate crosslinked or not thin sponge collagenous membranes (SCMs) that are suitable for TERM purposes. Two types of FSs, of the four tested, were able to generate SCMs, either from crosslinking or not, and showed good mechanical properties, enzymatic degradation resistance, water binding capacity, antioxidant activity, and biocompatibility on both fibroblast and keratinocyte cell cultures. Finally, our results demonstrate that it is possible to adapt the extraction procedure in order to alternatively improve the mechanical properties or the antioxidant performances of the derived biomaterial, depending on the application requirements, thanks to the versatility of *C. reniformis* extracellular matrix extracts.

**Keywords:** collagen; Porifera; biomaterials; tissue engineering; membranes
