Photocrosslinking, micropatterning and cell adhesion studies of sodium hyaluronate with a trisdiazonium salt

► Sodium hyaluronate is directly photocrosslinked with a trifunctional diazonium salt. ► The photocrosslinking process does not require a photoinitiator. ► Cell adhesion in these polymers strongly depends on the photocrosslinking degree. ► The photocrosslinking process can be applied to other natural polymers. Chemically unmodified sodium hyaluronate has been crosslinked by photoinduced decomposition of a trifunctional diazonium salt to generate new biomaterials. In addition, the photocrosslinking process does not require a photoinitiator. Thin films of formulations of sodium hyaluronate and the photocrosslinker at different percentages have been processed. Cytotoxicity has been explored and toxicity was not observed with the selected cell lines. 2D patterns of controlled geometry have been generated by direct laser writing to perform cell adhesion studies. Different adhesion behavior of the cell lines, as assessed by vinculin immunostaining and scanning electron microscopy, has been observed in the polymeric films depending on the degree of photocrosslinking.