As shown in Fig. This result indicates that the micro-patterns can be used to regulate surface droplet transportation. In fact, the transport velocity is a linear function of water droplet volume on the patterned surface when the PNIPAm lines are set in the vertical direction.
However, there is a critical value of around 10 μL for the droplet to move when the lines are set in the horizontal direction, as like on the smooth surface (Fig. 6d, Supplementary Figs.28, 29). The experimental results demonstrate that the vertically patterned surface could induce faster water transport, and the transport velocity depends on the water droplet volume. We adopted https://bookkeeping-reviews.com/ the previously-developed technology22 to prepare DN hydrogels with no soft second network surface layer (Supplementary Fig.1). Then, the immersed PNaAMPS SN hydrogel was sandwiched between two flat plates to obtain a reaction cell. The plates were made of glass covered with a silicone-coated PET film. The reaction cell was compressed at a pressure of ~0.8 kPa for 12 h.
Specific applications of hydrogels with surface microstructures
Modulation and characterization of the double network hydrogel surface-bulk transitionM Frauenlob, DR King, H Guo, S Ishihara, M Tsuda, T Kurokawa, H Haga, … Force-triggered microstructure growth of various polymers. Matsuda, T. & Sugawara, T. Development of surface photochemical modification method for micropatterning of cultured cells.
Recently, we have shown that double-network hydrogels are excellent materials to bridge the above-mentioned gap between molecular mechanisms and material functions. In a DN hydrogel, the force-triggered chemical reaction could be well-controlled by macroscopic force, and the reaction could be highly efficient. The stress concentration of the rigid and brittle Martin Frauenlob network caused by bond breaking could be effectively suppressed by the presence of the soft and stretchable networks16,17. Therefore, the force-activated bond breaking in a DN hydrogel does not cause catastrophic failure of the material, and the amount of bond breaking inside a DN hydrogel increases with the stress/strain imposed on the material18.
Dispersible hydrogel force sensors reveal patterns of solid mechanical stress in multicellular spheroid cultures
Specifically, cyclic temperature and pH changes bring about 30–50% reversible change in the height of micro-features formed in NIPAm and AAc, respectively (Fig.3d, Supplementary Fig.23). Since the bulk DN hydrogel is insensitive to heat or pH change, the induced surface microstructures could be controlled by these stimuli without altering bulk properties. The mouse myoblast cell line C2C12, labelled with GFP, was purchased from RIKEN Cell Bank. The cells were cultured in Dulbecco’s modified Eagle’s medium containing 10% foetal bovine serum and 1% penicillin/streptomycin at 37 °C in a humidified atmosphere containing 5% CO2. The 4–7th passages of the C2C12 cells were used in this study.
In this 8 sheet, 32 scene anonymous blockbook, lines from the biblical ‘Song of Songs’ are rearranged to form a new poem telling the story of the Virgin Mary’s preparation to take her place in the Christian hierarchy. The analysis puts the sheets into their proper order for this purpose and places the images, for the first time, in their art historical context. The result is a view of this small woodcut publication as the ‘Sistine Ceiling’ of the blockbook genre that was about to become extinct. The outcome of the analysis is based on biblical, anthropological and philosophical premises, resorting to New Criticism methodology, Close Reading and Hermeneutics. Q.M., K.C., T.N., and J.P.G. conceived the concept; Q.M., K.C., T.M., Z.W., H.K., S.N., T.Y., M.F., M.T., and S.T. Designed the experiments; Q.M., Z.W., H.K., S.N., T.N., M.T., S.T., and T.N.
Patterning of DN hydrogel surfaces
The on-demand micro-patterns with a variety of geometries and chemistries show promising biomimetic applications. We thus envision that our rapid patterning strategy and micropatterned tough DN hydrogels hold promise for microsensor arrays, soft adhesion, flexible displays, and biomedical devices. Our mechanochemical strategy of force-triggered microstructure growth is depicted in Fig.1a.
- Here, we show two application examples of the hydrogels with force-triggered growth of surface microstructures.
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- In fiscal year NAL delivered more than 100 million direct customer service transactions.
- This force-triggered method to chemically engineer the hydrogel surfaces provides a new tool in addition to the conventional methods using light or heat, and will promote the wide application of hydrogels in various fields.
- The stress concentration of the rigid and brittle network caused by bond breaking could be effectively suppressed by the presence of the soft and stretchable networks16,17.
Mu, Q. F. Robust multiscale-oriented thermoresponsive fibrous hydrogels with rapid self-recovery and ultrafast response underwater. ACS Appl.