Figure 6.

Human lung epithelial carcinoma (A549) cells were cultured in the presence of hydrogel sub-microspheres for 24 hours in standard growth culture medium at 37°C and 5% CO₂. A549 mitochondrial activity was determined using an absorbance-based quantitative assay; absorbance data for the groups treated with sub-microspheres were normalized to the non-treated cell control (average ± standard deviation, n = 6 hydrogel samples per group). The cytotoxicity of Alg-MA sub-microspheres was analyzed on (A) blank (non-loaded) sub-microspheres. The bioactivity of doxorubicin (DOX) was verified using (B) DOX-loaded sub-microspheres. Various groups (white diamonds = green photo-crosslinked, white circles = UV photo-crosslinked, black diamonds = green + Ca²⁺ dual-crosslinked, black circles = UV + Ca²⁺ dual crosslinked) and sub-microsphere concentrations (10, 50, 100 μg/mL) were characterized.