Based on these pre-screening results, 7.5wt% gelatin hydrogels crosslinked with 0.1wt% genipin were chosen for further investigation with bacterial supernatant. Bacterial strains were grown in Brain Heart Infusion (BHI) or Tryptic Soy Broth broths for 18 h at 37 °C and were then centrifuged at 4000 rpm for 10 min to collect cell-free supernatant containing proteases. Supernatants from 36 bacterial strains were tested, comprising both Grampositive and Gram-negative human pathogens. A simple assay was designed where crosslinked sterilized hydrogels were prepared in the bottom of 12-well plates. A disc of gel was cut and removed from the centre of the plate and the supernatant was then pipetted into the circular space. If the gel degraded, the central well was filled with solubilized fragments of the blue gel and turned blue (Figure ). It was shown the autoclaving process to obtain sterile hydrogels did not impact the degradation result ( Figure and Table ).