The present CD laboratory is focused towards the development of modified biopolymers for ocular and dermal use. Biopolymers are attractive for ocular applications due to their excellent safety profile with minimal toxicity. Molecules like hyaluronic acid (HA) or chitosan have been extensively studied in research both in the fields of ophthalmology and dermatology. Hyaluronic acid, for example, is used since many years as a lubricant substance for wetting the ocular surface in patients with dry eye disease (DED). In addition, due to its high biocompatibility and its common presence in the extracellular matrix of tissues, it gained popularity as a biomaterial scaffold in tissue engineering. Similarly, chitosan, a cationic biodegradable biopolymer, has drawn attention for ocular drug delivery based on its mucoadhesivity. It offers a permeation-enhancement for delivering materials across the cell surface, especially on mucosal surfaces.
Thiolated polymers (Thiomers) are mucoadhesive polymers which display thiol bearing side chains. With these modifications, the polymers exhibit new physical properties including improved mucoadhesion. In ocular applications thiolated chitosan might therefore overcome the general problem of all lubricants, which are characterized by a relatively short residence time on the ocular surface. In addition, due to the thiol groups, thiomers have more reactivity and enhanced protection against oxidation. Furthermore, there have been described properties related to permeation enhancement, in situ gelation and efflux inhibition.
The research within the CD laboratory is performed in cooperation with two industrial partners - Croma-Pharma, an Austrian family-owned company based in Leobendorf and Carl Zeiss Meditec located in Dublin, California. While the research with Croma Pharma is directed towards the pharmacological aspects and applicability of thiomers, Carl Zeiss Meditec’s main objective is the medical imaging of the eye for improved characterization of DED.
Therefore, two major topics are addressed in the scope of the Christian Doppler:
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