Given the high interest on the use of biopolymers in many fields of medicine [1], this project aims to merge material design based on a microbial biopolymer with an innovative ionic liquid (IL) chemistry to develop skin drug delivery biomaterials in the form of films or hydrogels. To accomplish this objective, a multidisciplinary strategy will be followed that combines biopolymer production, organic chemistry and pharmaceutical technological challenges.
The microbial biopolymer that will be used in this project is the chitin-glucan complex (CGC), that combines the biological properties of chitin and glucan resulting into a biocompatible material with intrinsic antimicrobial activity and wound healing capacity [2-4]. Despite its valuable physical and biological properties, CGC full potential for biomedical applications has been hindered by its insolubility in water and most organic and inorganic solvents.
Ionic liquids (ILs) have been reported to be alternative solvents to dissolve biopolymers (e.g. chitin [5-9], cellulose [10] and chitosan [11-13]). By an appropriate selection of the anion and the cation, it is possible to tune the design of ILs with completely different properties. Motivated by the possibility of tailoring ILs, innovative and challenging synthetic routes will be developed in this project to synthetize ILs with double function. ILs composed by a combination of pharmaceutical drugs (anti-bacterial, anti-microbial and anti-inflammatory drug) as cation and hydrogen bonds disruptive properties (mandatory to dissolve CGC) as anion will be synthetized. This will open up the perspective of using ionic liquids not only as solvents to dissolve CGC biopolymer, but also to play an active role on the delivery of drugs through skin when present in the CGC-based free-standing films or hydrogels.
Within this project, it is expected to obtain deep knowledge on the (i) production and characterization of CGC biopolymer; (ii) design and characterization of innovative biocompatible ILs with double function (biopolymers dissolution and therapeutic properties); (iii) understand CGC dissolution mechanism using ILs; (iv) preparation and characterization of tailor-made CGC polymeric structures; (iv) preliminary assessment of the biological properties of CGC polymeric structures.
In order to successfully achieve the objectives of the project, the IR has gathered a multidisciplinary team, experienced in the production and characterization of microbial biopolymers, in the synthesis and use of ILs, in the design and characterization of polymeric structures and in biocompatibility evaluation [Farinha2005; Rosatella2016; Frade2013; Martins2016; Neves2016]. The IR has a strong background in the design and characterization of different polymeric materials by incorporation of ionic liquids. Additionally, the IR supervised two master thesis related with the design and characterization of CGC films obtained by the dissolution of the polymer in ILs [14-15].