Udo KRAGL1, Johanna MEYER2, Fridolin SOMMER1, Johanna ROMISCHKE1, Ann JASTRAM1
1University of Rostock, Rostock, Germany
2University of Hannover, Hannover, Germany
Ionic liquids itself have the potential for many interesting applications, which has been demonstrated over the last two decades. Adding additional functional groups or using alternative building blocks will allow to achieve special properties or open up new routes and materials. Based on early work of Ohno and coworkers we have introduced functional groups which will result in polymerized ionic liquids. [1] These polyelectrolytes have been successfully applied in the following areas:
Photoinitiated copolymerization vinylalkylimidazolium bromide with styrene derivatives yields free-standing membranes with an adjustable thickness. presented. By the variation of alkyl side chains, membrane characteristics such as flux and mechanical properties can be adjusted. The simultaneous use of different ionic liquids (ILs) in the synthesis can also improve the membrane properties. The membranes have been used for separation of charged carbohydrates such as calcium gluconate from neutral compounds such as glucose as well as for electrodialysis. [2]
Polymerized ionic liquids as well as the monomers itself inherit antibacterial activity against methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa strains. Depending on the strain and the PIL antibacterial activity with nearly 100% eradication was observed. At the same time, the materials showed excellent biocompatibility towards mouse fibroblasts. These findings are very promising for the development of new antibacterial materials for medical applications, for example, stent coatings. [3]
An additional crosslinking of the hydrogels with N,N?-methylenebisacrylamide (MBAA) or different lengths of poly(ethyleneglycol)diacrylate (PEGDA) yield ideal materials for drug delivery systems. Contrary to for example hydrogels based on hyaluronic acid this material can be sterilized easily by gamma radiation. The results for drug release profiles show an ion exchange depending release instead of a diffusion-controlled drug release as it is known form common drug delivery systems. [4] T
To understand transport properties as well as exchange processes swelling and diffusion in PIL-based hydrogels has been investigated. Diffusion coefficients were estimated with interval sorption experiments as well as magnetic resonance imaging. [5]
References
[1] Solid State Ionics 2018, 314, 119-128
[2] Membranes 2020,10, 0308
[3] J Appl Polym Sci 2021, 138, e50222
[4] Macromol BioSci 2020, 2000152
[5] Polymers 2021, 13, 1834