An effective treatment of human diseases using regenerative medicine and cell therapy approaches requires a large number of cells. Cultivation of cells on microcarriers is a promising approach due to the high surface‐to‐volume ratios that these microcarriers offer. Here, multifunctional temperature‐responsive microcarriers (cytoGel) made of an interpenetrating hydrogel network composed of poly(N‐isopropylacrylamide) (PNIPAM), poly(ethylene glycol) diacrylate (PEGDA), and gelatin methacryloyl (GelMA) are developed. A flow‐focusing microfluidic chip is used to produce microcarriers with diameters in the range of 100–300 μm and uniform size distribution (polydispersity index of ≈0.08). The mechanical properties and cells adhesion properties of cytoGel are adjusted by changing the composition hydrogel composition. Notably, GelMA regulates the temperature response and enhances microcarrier stiffness. Human‐derived glioma cells (U87) are grown on cytoGel in static and dynamic culture conditions with cell viabilities greater than 90%. Enzyme‐free cell detachment is achieved at room temperature with up to 70% detachment efficiency. Controlled release of bioactive molecules from cytoGel is accomplished for over a week to showcase the potential use of microcarriers for localized delivery of growth factors to cell surfaces. These microcarriers hold great promise for the efficient expansion of cells for the industrial‐scale culture of therapeutic cells.

Irradiation of azomaterials causes various photophysical and photomechanical effects that can be exploited for the preparation of functional materials such as surface relief gratings (SRGs). Herein, we develop and apply an efficient strategy to optimize the SRG inscription process by decoupling, for the first time, the important effects of the azo content and glass transition temperature (T). We prepare blends of a photoactive molecular glass functionalized with the azo Disperse Red 1 (gDR1) with a series of analogous photopassive molecular glasses. Blends with 10 and 40 mol % of gDR1 are completely miscible, present very similar optical properties, and cover a wide range of T from below to well above ambient temperature. SRG inscription experiments show that the diffraction efficiency (DE), residual DE, and initial inscription rate reach a maximum when T is 25-40 °C above ambient temperature for low to high azo content, respectively. Indeed, for a fixed 40 mol % azo content, choosing the optimal T enables doubling the SRG inscription rate and increasing DE 6-fold. Moreover, a higher azo content enables higher DE for a similar T. Spectroscopy measurements indicate that the photo-orientation of DR1 and its thermal stability are maximal with T around 70 °C, independent of the azo content. We conclude that the SRG potential of azomaterials depends on their capability to photo-orient but that the matrix rigidity eventually limits the inscription kinetics, leading to an optimal T that depends on the azo content. This study exposes clear material design guidelines to optimize the SRG inscription process and the photoactivity of azomaterials.

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