One-Pot Preparation of Hydrophilic Polylactide Porous Scaffolds by Using Safe Solvent and Choline Taurinate Ionic Liquid

Abstract

Polylactides (PLAs) are a class of polymers that are very appealing in biomedical applications due to their degradability in nontoxic products, tunable structural, and mechanical properties. However, they have some drawbacks related to their high hydrophobicity, lack of functional groups able to graft bioactive molecules, and solubility in unsafe solvents. To circumvent these shortcomings, porous scaffolds for tissue engineering were prepared by vigorously mixing a solution of isotactic and atactic PLA in nontoxic ethyl acetate at 70 °C with a water solution of choline taurinate. The partial aminolysis of the polymer ester bonds by taurine -NH2 brought about the formation of PLA oligomers with surfactant activity that stabilized the water-in-oil emulsion. Upon drying, a negligible shrinking occurred, and mechanically stable porous scaffolds were obtained. By varying the polymer composition and choline taurinate concentration, it was possible to modulate the pore dimensions (30–50 µm) and mechanical properties (Young’s moduli: 1–6 MPa) of the samples. Furthermore, the grafted choline taurinate made the surface of the PLA films hydrophilic, as observed by contact angle measurements (advancing contact angle: 76°; receding contact angle: 40°–13°). The preparation method was very simple because it was based on a one-pot mild reaction that did not require an additional purification step, as all the employed chemicals were nontoxic.

Wetting of Superhydrophobic Polylactic Acid Micropillared Patterns

“…The apparent θ on the flattened PLA layer was measured to be 81 ± 1°, which fits the value reported in the literature for the apparent θ on a flat PLA as 80 ± 1° . In the present study, θ a and θ r values on the flattened PLA were measured to be 93 ± 1 and 50 ± 2°, respectively, as seen in Table , which were very close to the reported values of 91 and 50° in the literature . θ values on the flat PLA were used to calculate the theoretical contact angles on the pillared PLA patterns using Cassie–Baxter and Wenzel equations and are given in Table S3 of the Supporting Information.…”

“… 92 In the present study, θ a and θ r values on the flattened PLA were measured to be 93 ± 1 and 50 ± 2°, respectively, as seen in Table 5 , which were very close to the reported values of 91 and 50° in the literature. 93 θ values on the flat PLA were used to calculate the theoretical contact angles on the pillared PLA patterns using Cassie–Baxter and Wenzel equations and are given in Table S3 of the Supporting Information. None of the experimental apparent θ results on the pillared PLA patterns fit the theoretical θ estimates as expected.…”

Progress in the applications of biocompatible ionic liquids: renewable commodity production, catalytic and pharmaceutical approaches – a review

“…Likewise, cytotoxicity tests demonstrated its non-toxicity and application as a solvent to make hydrophilic polylactide porous scaffolds. 128…”

Bioionic Liquids: Enabling a Paradigm Shift Toward Advanced and Smart Biomedical Applications

“…While the imidazolium ILs’ performance overall surpassed that of the BILs’, it was offset by the excellent cytocompatibility shown by the BILs with exceptional C2C12 cell proliferation. [ 117 ] Chitosan is a well‐received cationic polyelectrolyte polymer that has been used in a wide variety of biomedical applications. In 2013, Brett et al used chitosan, a cationic polyelectrolyte, with choline dihydrogen phosphate and choline chloride BILs to develop biocompatible and biodegradable materials for improved electrical and pH‐sensitive properties.…”