Skip to main content

In situ polymerising depot system for stimulus-responsive release of (ionic) agents


The invention concerns a novel, polymer-based drug depot system which is introduced into the human body, where it enables a continuous release of the active substance and finally completely degrades again.


In recent decades, medical technology research has developed ground-breaking innovations for the more effective use of medicines. However, the conventional forms of administration used to date, such as oral administration by tablet or the application of active ingredient solutions or emulsions by injection, have some disadvantages. In oral administration, for example, the active ingredient is absorbed systemically via the gastrointestinal tract, which means that increased concentrations of the active ingredient must be applied in order to achieve the desired effect. This often results in side effects that occur away from the actual site of action. Although the administration of the active ingredient by injection allows the drug to be used locally, it is cumbersome, uncomfortable and painful. It can considerably impair the patient's quality of life in the case of prolonged therapy.


In addition to improvements for oral and intravenous application, so-called drug delivery systems offer a completely new possibility for controlled drug release. A reservoir is placed in or on the body from which a drug is released in a controlled manner. Drug delivery systems are now being used more and more frequently because the targeted local and temporal application of medical agents is becoming more important.


The present invention can reduce and proportionally even resolve some of the disadvantages of the drug depot systems used so far for subcutaneous, subconjunctival and intramuscular applications. ELA-NCO (a functionalised ethylene-glycol-di-lactic acid) serves as biodegradable matrix. Microparticles of an electrolyte hydrogel loaded with the active substance are embedded in this matrix. The special thing about this is that the two components are mixed and polymerise only during the application in the human body. As a result, the active ingredient depot in the body can take on a form that corresponds to the space available. This makes the system according to the invention suitable for several applications in the field of subcutaneous, subconjunctival or intramuscular treatment compared to other drug depot systems, which usually have only one field of application.

In addition, the interaction of the ionically functionalised hydrogel system allows a stimulus-responsive release, for example through an exchange reaction with ions in the solution or other processes, to be achieved over a fixed period of up to one year without active intervention by the patient or the doctor. The locally controllable and continuous release of the active substance is to be emphasised as an innovative feature of the invention, as this avoids or reduces the risk of uncontrolled, abrupt release, as may occur in purely diffusion- and degradation-controlled release processes.

Afterwards, the depot system in the body decomposes independently, so that no intervention is required to remove it.


»         Active ingredient depot system with continuous and controllable release of active ingredient

»         independent breakdown of the drug delivery system in the human body

»         Sterilisability also by gamma rays

Scope of application

Biomedical engineering, Chemistry, Materials Engineering, Pharmacy


The German patent application is pending. We are looking for companies for commercial use as well as for development cooperations.

Universität Rostock Service GmbH

Dipl.-Ing. Lars Worm
+49 381 498-9803
Parkstraße 6
18057 Rostock

Development status


Patent situation

  • DE pending

Offer at Providers website

Contact | Main Office

TransferAllianz e. V.
Christiane Bach-Kaienburg

c/o TransMIT GmbH
Kerkrader Straße 3
D-35394 Gießen