Purpose Estradiol (E2)-loaded poly(L-lactide-co-glycolide-trimethylenecarbonate) (P(L-LA:GA:TMC)) rods with shape-memory were developed for the treatment of neurodegenerative diseases. Usefulness of the extrusion method in the obtaining process was also considered. The influence of structural and surface properties during hydrolytic degradation was developed. The possible therapeutic aspect of rods with E2 was determined. Methods The extruded rods were incubated in a PBS solution (pH 7.4, 37°C, 240 rpm). The amount of released E2 in vitro conditions was estimated by UV-VIS method. The following methods in the degradation of rods were applied: NMR, DSC, FTIR, GPC, SEM, and optical microscopy. Changes in water uptake and weight loss were also determined. In vivo study was performed on rats. Measurements of E2 level were performed before and after ovariectomy of rats using ELISA method. A sample of tissue adjacent to the site of the rod implantation was analysed under an optical microscope. Results A stable and steady degradation process ensured zero-order release of E2. The in vivo study indicated a significant increase in the E2 level in serum after ovariectomy. Moreover, structural and surface features indicated that the extrusion method was appropriate for obtaining E2-loaded rods. Conclusions Shape-memory P(L-LA:GA:TMC) rods with E2 are an adequate proposal for further research in the field of neurological disorders.

Purpose: The blood-brain barrier limits the application of idarubicin in the therapy of glioblastoma multiforme. Biodegradable, intracranial wafers with prolonged release may increase therapy efficiency. Methods: Blank wafers, wafers containing 5% w/w and 10% w/w of idarubicin were formulated by solution casting from poly(L-lactide-co-glycolide) and poly(glycolide-co-ε-caprolactone). The following methods were used: NMR, GPC, DSC, FTIR, AFM, UV-VIS, and a viability and proliferation assay for idarubicin action (U87MG cell line). Results: Wafers showed a surface with numerous immersions and hills. A lack of interactions between idarubicin and the copolymers was observed. The substance was entrapped in the matrix and released in two phases for all wafers with the appropriate bolus and maintenance dose. The burst effect was observed for all wafers, however, the biggest bolus for poly(L-lactide-co-glycolide) wafers containing 5% w/w of idarubicin was noted. The stable and steady degradation of poly(glycolide-co-ε-caprolactone) wafers containing 5% w/w of idarubicin ensures the most optimal release profile and high inhibition of proliferation. Conclusions: Copolymer wafers with idarubicin are an interesting proposition with great potential for the local treatment of glioblastoma multiforme. The release rate and dose may be regulated by the amount and kind of wafers for various effects.

In recent years, fibrin has been successfully used as a polymer drug delivery carrier. Passive properties of fibrin provide parenteral and local delivery of drug substances in controlled and prolonged manner and also tissue support, gluing and sealing. Fibrin also has hemostatic and proangiogenic effects. Discs, films, gels, beads and nanoparticles are among the most commonly proposed and used fibrin-based formulations. It is routinely obtained from fibrinogen and thrombin. Fibrin formulation methods are solution casting, dual syringe systems and emulsification. All fibrin formulations become gel after administration and water absorption. Biodegradation and biocompatibility are important advantages of fibrin, which make it possible to implant a formulation without the need to remove the carrier from the body after the drug is released. Fibrin-based drug delivery systems are proposed and applied in the treatment of wounds, infections and cancerous diseases.