Sample CS or HA release (%) PVA 9%-CSA 1% 0.4 PVA 9%-CSA 2% 0.3 PVA 9%-HA 1% 1.5 PVA 9%-HA 2% 23 PVA 9%-CSA 1% 37.5

Table 2: Release of CS and HA respectively from PVA- CS and PVA-HA materials. The release is calculated as released biopolymer (%) = [(biopolymer mass in the medium (g)/biopolymer total mass in the analysed specimen (g) )] * 100.