Study of natural and chemically modified natural polymers for biotechnological applications

Several natural or synthetic polysaccharides are able to form, under appropriate conditions, physically or chemically crosslinked supramolecular structures and, together with their biocompatibility, this explains their wide use in food, pharmaceutical, cosmetics and biomedical sectors.
These interconnected structures, commonly named gels or hydrogels, are very adaptable materials, suitable for diverse applications because of their fast response to different external stimuli such as pH, temperature, humidity and ionic strength. Due to these peculiar properties, in the last decade, hydrogels have found applications as wound dressing and healing device. Protection from infection and traumas is the most fundamental and traditional role of wound dressings in the medical practice. In more recent times, further features have been added, such as the ability to provide oxygenation, hydration, absorption of wound fluids and exudates, to release growth factors, to prevent and treat infectious states. Hydrogel wound dressings are generally non-adhesive to the skin and high conformable, therefore particularly apt to be used in patients with thin or fragile skins. Hydrogels can be self-standing films, coatings of textiles or adjoined with other synthetic materials. The incorporation of diagnostic tools/drugs, such as RFID sensors or anti-microbial agents, can be of great aid to ensure fast and controlled healing.
Food is another field in which polysaccharide hydrogels are widely used. They are mainly utilized to provide jelly-like consistency, as stabilizer, gelling and thickening agent. Although polysaccharides possess a similar chemical structure, their rheological properties can be very different and rheology can give key suggestions for different applications. Rheological techniques and tests, employed for many decades in the characterization of synthetic polymers, are used in our Laboratory to understand the properties of natural or chemically modified natural polymers for food applications. Up to now, investigations have been performed on agarose, -carrageenan and pectin.
Tissue engineering aims to provide alternative living tissue substitutes that restore, maintain or improve tissue functions. Ideally, biomaterials for tissue engineering should perform the structural, chemical and mechanical functions physiologically provided by the extra-cellular matrix. 3D scaffolds are tools made of polymeric biomaterials and have the advantage to provide a structural support for cell attachment and tissue development. In our Laboratory, the functional properties of hydrogels and their ability to constitute the optimal 3D environment for cell survival, differentiation and growth are investigated, using both differentiated cells lines and Spheroids derived from Adipose Stem Cells isolated from voluntary donors. In the latter case, the cell attachment and differentiation strongly depend on the hydrogel strength and porosity, thus rheological studies play a key role in determining the cell fate.
The present research line is done in close cooperation with Prof. C. Dispenza and Ing. M.A. Sabatino (Dipartimento dell’Innovazione Industriale e Digitale) dell’Università di Palermo.

Members:
Donatella Bulone
Maria Assunta Costa
Lorena Anna Ditta
Daniela Giacomazza (Principal investigator)
Rosa Passantino
Pier Luigi San Biagio