Designing a Transparent and Fluorine Containing Hydrogel

Physical hydrogels are supramolecular materials obtained by self-assembly of small molecules called gelators. Aromatic amino acids and small peptides containing aromatic rings are good candidates as gelators due to their ability to form weak bonds as pi-pi interactions and hydrogen bonds between NH and CO of the peptide chain. In this paper we show our results in the preparation of a transparent hydrogel that was obtained by self-assembly of a fluorine-containing dipeptide that relies on the additional formation of halogen bonds due to the fluorine atoms contained in the dipeptide. We used Boc-D-F(2)Phe-L-Oxd-OH (F(2)Phe = 3,4-difluorophenylalainine; Oxd = 4-methyl-5-carboxy-oxazolidin-2-one) that formed a strong and transparent hydrogel in 0.5% w/w concentration at pH = 4.2. The formation of a hydrogel made of unnatural fluorinated amino acids may be of great interest in the evaluation of patients with parkinsonian syndromes and may be used for controlled release.

Automated summary

This study demonstrated the preparation of a transparent physical hydrogel through the self-assembly of a fluorine-containing dipeptide that relies on the additional formation of halogen bonds. The dipeptide used formed a solid and transparent hydrogel at 0.5% w/w concentration and may have potential applications in the evaluation and controlled release for patients with parkinsonian syndromes.