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This study reports the fabrication of non-woven fibrous membranes from electrospinning blended solutions of PVDF with a random polyampholyte amphiphilic copolymer (r-PAC) inN,N-dimethylformamide and methanol. 

Abstract Conventional drug delivery methods often face challenges in terms of patient adherence and drug administration. Microneedles (MNs) patches have emerged as a promising alternative, offering a minimally invasive transdermal route for medications. However, their drug‐loading capacity remains limited, particularly for hydrophobic active pharmaceutical ingredients (APIs). Herein, microneedles are designed based on eutectic solvent gels (eutectogels) as transdermal carriers for hydrophobic APIs. A natural deep eutectic solvent (NADES) is combined to enhance the solubility of the hydrophobic APIs within the GelMA/PEGDA matrix for mechanical strength and sustained release from the resulting eutectogels microneedles (EU‐MNs). Using docetaxel, 5‐fluorouracil, and curcumin as hydrophobic APIs models, the superior drug‐loading capacity of the EU‐MNs is demonstrated. In vitro experiments revealed that the EU‐MNs provided a sustained release of distinct hydrophobic APIs over 4 days. Additionally, by properly adjusting the concentration and type of APIs, these microneedle patches do not exhibit cytotoxic effects on fibroblasts cell line (NIH/3T3), underscoring their potential for safe and effective transdermal drug delivery. These findings highlight the potential of EU‐MNs as versatile, eco‐friendly transdermal vehicles for large amounts of hydrophobic APIs, leading to more effective treatments for these drugs. 

The synthesis of 1-butyl-2,3-dimethyl-4-vinylimidazolium triflate, its polymerization, and ion exchange to yield a trio of 1-butyl-2,3-dimethyl-4-vinylimidazolium polymers is described. Irrespective of the nature of the anion, substitution at the 2-position of the imidazolium moiety substantially increases the distance between the anion and cation. The methyl substituent at the 2-position also served to expose the importance of H-bonding for the attractive potential between imidazolium moiety and anions in polymers without a methyl group at the 2-position. The thermal characteristics of poly(1-butyl-2,3-dimethyl-4-vinylimidazolium) salts and corresponding poly(1-ethyl-3-methyl-4-vinylimidazolium) salts were evaluated. While the mid-point glass transition temperatures, Tg-mid, for 1-ethyl-3-methyl-4-vinylimidazolium polymers with CF3SO3−, (CF3SO2)2N− and PF6− counterions, were 153 °C, 88 °C and 200 °C, respectively, the Tg-mid values for 1-butyl-2,3-dimethyl-4vinylimidazolium polymers with corresponding counter-ions were tightly clustered at 98 °C, 99 °C and 84 °C, respectively. This dramatically reduced influence of the anion type on the glass transition temperature was attributed to the increased distance between the center of the anions and cations in the 1-butyl-2,3-dimethyl-4-vinylimidazolium polymer set, and minimal H-bonding interactions between the respective anions and the 1-butyl-2,3-dimethyl-4-vinylimidazolium moiety. It is believed that this is the first observation of substantial independence of the glass transition of an ionic polymer on the nature of its counterion. 

Silk fibroin, regenerated from Bombyx mori, has shown considerable promise as a printable, aqueous-based ink using a bioinspired salt-bath system in our previous work. Here, we further developed and characterized silk fibroin inks that exhibit concentration-dependent fluorescence spectra at the molecular level. These insights supported extrusion-based 3D printing using concentrated silk fibroin solutions as printing inks. 3D monolithic proteinaceous structures with high aspect ratios were successfully printed using these approaches, including cantilevers only supported at one end. This work provides further insight and broadens the utility of 3D printing with silk fibroin inks for the microfabrication of proteinaceous structures. 

The exceptional elastic resilience of some protein materials underlies essential biomechanical functions with broad interest in biomedical fields. However, molecular design of elastic resilience is restricted to amino acid sequences of a handful of naturally occurring resilient proteins such as resilin and elastin. Here, we exploit non-resilin/elastin sequences that adopt kinetically stabilized, random coil–dominated conformations to achieve near-perfect resilience comparable with that of resilin and elastin. We also show a direct correlation between resilience and Raman-characterized protein conformations. Furthermore, we demonstrate that metastable conformation of proteins enables the construction of mechanically graded protein materials that exhibit spatially controlled conformations and resilience. These results offer insights into molecular mechanisms of protein elastomers and outline a general conformation-driven strategy for developing resilient and functional protein materials.