Biocompatibility testing is usually performed through staining and imaging of cell lines. We propose here to monitor cytotoxicity through real‐time measurement of metabolites specifically issued from cell stress behaviour using a multiparametric electrochemical (bio)sensing platform. However, the composition of culture media varies widely according to the requirements of the utilized cell lines. This matter may have significant effects on the sensor's sensitivity. With this mind, the sensitivity of four electrochemical (bio)sensors (pH, hydrogen peroxide, nitric oxide/nitrite (NO and its by‐product) and lactate) is investigated in different cell culture media. The main culture media studied were Minimum Essential Medium Eagle (MEM), Dulbecco's Modified Eagle Medium (DMEM), Williams’ Medium E and RPMI 1640 medium that were the recommended culture media for the cell types to be monitored. This work shows the impact of the different cell culture media on the performances of the different sensors (limit of detection, sensitivity, selectivity, response time and dynamic range). More particularly, FBS strongly impacts the response of the amperometric (bio)sensors. Then, cellular viability testing was effected within optimized medium (FBS content) for electrochemical sensor read‐outs in the case of short‐term cultures (one day) devoted to cytotoxicity testing. Real‐time electrochemical monitoring provides important additional information about cell behaviour during biocompatibility testing that might be further implemented in different settings including pharmaceutical efficacy and biomaterials applications.

Implantation of biomedical devices is followed by immune response to the implant, as well as occasionally bacterial, yeast, and/or fungal infections. In this context, new implant materials and coatings that deal with medical device‐associated complications are required. Antibacterial and anti‐inflammatory materials are also required for wound healing applications, especially in diabetic patients with chronic wounds. In this work, hyaluronic acid (HA) hydrogels with triple activity: antimicrobial, immunomodulatory, and miRNA delivery agent, are presented. It is demonstrated that polyarginine with a degree of polymerization of 30 (PAR30), which is previously shown to have a prolonged antibacterial activity, decreases inflammatory response of lipopolysaccharide‐stimulated macrophages. In addition, PAR30 accelerates fibroblast migration in macrophage/fibroblast coculture system, suggesting a positive effect on wound healing. Furthermore, PAR30 allows to load miRNA into HA hydrogels, and then to deliver them into the cells. To the authors knowledge, this study is the first describing miRNA‐loaded hydrogels with antibacterial effect and anti‐inflammatory features. Such system can become a tool for the treatment of infected wounds, e.g., diabetic ulcers, as well as for foreign body response modulation.