Preparation of cross-linked biocompatible poly(2-methacryloyloxyethyl phosphorylcholine) gel and its strange swelling behavior in water/ethanol mixture

Abstract

Functional cross-linked poly(2-methacryloyloxyethyl phosphorylcholine(MPC)) gels were prepared with various cross-linkers by conventional radical polymerization in aqueous media. The poly(MPC) gels swelled in water and have a large degree of swelling compared with that of poly(2-hydroxyethyl methacrylate). The swelling degree of the poly(MPC) gel equilibrated in water depended on the chemical structure and composition of the cross-linkers, but did not change in an aqueous medium with pH and ionic concentrations. On the other hand, the volume of poly(MPC) gel changed sharply with a change in the composition of water/ethanol mixtures. Although in mixtures containing 70-90 vol% of ethanol the gel volume was nearly 10% of that in water, in pure ethanol it was almost the same as in water. The change in the volume of the poly(MPC) gel observed in a water/ethanol mixture was completely reversible. We conclude that this so-called re-entrant phenomenon was derived from the co-nonsolvency of poly(MPC) in the water/ethanol mixture triggered by an imbalance in the delicate interaction force between the molecules of water, ethanol, and poly(MPC).

Molecular recognition of alcohol by volume phase transition of cross-linked poly(2-methacryloyloxyethyl phosphorylcholine) gel

“…In our previous article, we observed a reversible change in the volume of the cross-linked poly(MPC) gel in response to the concentration change of EtOH in an aqueous medium [13]. Here, we also discussed the swelling behavior of the poly(MPC) gel in various water/alcohol mixtures.…”

“…We considered that if some additive, which can bind water molecules on it by hydration, will dramatically change the conformation of the poly(MPC) chain. In our previous report, the reentrant volume phase transition of the poly(MPC) gel in a water/ethanol (EtOH) mixture is described [13]. The volume of the poly(MPC) gel changed with the composition of EtOH in the mixtures due to the cononsolvency of the poly(MPC) in a water/EtOH mixture.…”

Preparation of a biomimetic polyphosphorylcholine monolithic column for immobilized artificial membrane chromatography

“…The lack of related researches could be attributed to the low efficiency of commercial IAM columns (10 m packings). It has been reported that the polymer surface with phosphorylcholine groups exhibit great properties in resisting protein adsorption and cell adhesion [37,38]. Take into account of higher column efficiency and good surface properties of the poly(MDPC-co-EDMA) monolith, it is of great interest to evaluate its' separation ability for intact proteins.…”

Investigation of the mechanisms for stable superlubricity of poly(vinylphosphonic acid) (PVPA) coatings affected by lubricant

“…However, the lubricity of MPC is reduced in toluene, probably due to more collapsed MPC brushes and decreased solvent uptake in the coating [25]. For the same reasons, MPC do not exhibit good tribological properties in ethanol and water mixtures [26]. In addition, with respect to polyelectrolytes, the compatibility of the charging characteristics between the ions in lubricants and polymer brushes is also a critical factor for reducing the friction coefficient, due to the influences of electrostatic and hydrophobic interactions [27].…”