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Biocompatible external stimuli-responsive hydrogels are of interest for drug delivery, cell and gene therapy, tissue engineering, protein patterning, and other biomedical applications. In this work, based on the biocompatible polymer poly(methyl vinyl ether-alt-maleic acid) (P(MVE-alt-MA)), host polymer β-cyclodextrin-grafted P(MVE-alt-MA) (P(MVE-alt-MA)-g-β-CD) and guest polymer azobenzene-grafted P(MVE-alt-MA) (P(MVE-alt-MA)-g-azo) were first prepared. Then through taking advantage of the traditional host–guest interaction of β-cyclodextrin and azobenzene, novel multiple stimuli-responsive physical P(MVE-alt-MA)-g-β-CD/P(MVE-alt-MA)-g-azo supramolecular hydrogels were obtained after simply mixing the aqueous solutions of the host polymer and guest polymer. The formation of the supramolecular hydrogels was also confirmed by 2D-NOESY. This kind of supramolecular hydrogels not only exhibits photo-, pH- and thermo-sensitivity, but also cytocompatibility. Ovarian cancer SKOV3 cells can survive within different hydrogel layers, which were observed by confocal microscopy. These results suggest that this multiple stimuli-responsive P(MVE-alt-MA)-based supramolecular hydrogel may be expected to have a powerful potential in biomedical applications as a three-dimensional (3D) cell culture matrix or as a vehicle for the delivery of drugs and therapeutic cells.

Ageing and remodelling of the extracellular matrix (ECM) leads to enzyme activation, resulting in a fibrotic microenvironment and fluctuating ECM stiffness. In this study, prepared egg white (EW) cross-linked with poly[(methyl vinyl ether)-alt-(maleic acid)] (P(MVE-alt-MA)) with macroporous structures were used to simulate an aged extracellular matrix that affected the malignant behaviour of cancer cells at different stages. Increased macroporosity and stiffness properties clearly enhanced the proliferation of cancer cells. In other words, different levels of EW cross-linking had different effects on cell malignancy, thereby determining the ability and speed of cell migration in scaffolds. The study showed that porosity and stiffness changes in the matrix were possible mechanisms for cancer cell invasion and metastasis besides blood vessels and lymphatic invasion in human body. P(MVE-alt-MA)-cross-linked EW contained a major component of ECM and provided a useful model to evaluate the proliferation and metastasis of cancer cells in vitro. This has important significance when it comes to exploring the effects of the material microenvironment on tumour prevention and treatment.