Molecularly imprinted cyclodextrin nanosponges for the controlled delivery of L-DOPA: perspectives for the treatment of Parkinson’s disease

Background: L-DOPA is an amino acid precursor to the neurotransmitter dopamine that is extensively used as a prodrug for the treatment of Parkinson’s disease. However, L-DOPA is an unstable compound: when exposed to light or added to aqueous solutions, it may degrade, compromising its therapeutic properties. Methods: In this work, a new type of drug-loaded cyclodextrin-based nanosponge, obtained using molecular imprinting, is described for the prolonged and controlled release of L-DOPA. The molecularly imprinted nanosponges (MIP-NSs) were synthesized by cross-linking β-cyclodextrin with 1,1ʹ-carbonyldiimidazole in DMF in the presence of L-DOPA as a template molecule. TGA, DSC and FTIR analyses were performed to characterize the interactions between L-DOPA and the two nanosponge structures. Quantitative NMR spectroscopy was used to determine the amount and the affinity of L-DOPA entrapped in the nanosponges. The in vitro L-DOPA release kinetics from the NSs were quantitatively determined by HPLC analysis. Results: The MIP-NSs show a slower and more prolonged release profile than the non-imprinted nanosponges. No degradation of the L-DOPA hosted in the MIP-NSs was observed after long-term storage at room temperature. Conclusions: The MIP-NSs are a promising alternative for the storage and controlled delivery of L-DOPA.