Figure 8. GAG release into the medium and retention in the constructs for PGA–alginate scaffolds cultured in bioreactors operated using a constant flow rate of 0.2 mL min⁻¹ (high flow rate, •), a gradually increasing flow rate of 0.075–0.2 mL min⁻¹ (gradual increase in flow rate, □), or scaffold pre-culture in T-flasks for 5 days prior to bioreactor culture at a constant flow rate of 0.2 mL min⁻¹ (5-day pre-culture, ▪).

(a) Cumulative amount of GAG released into the medium; (b) overall specific rate of GAG release (mg per day per mg of GAG in the constructs at harvest); and (c) percentage of total GAG (construct+medium) retained in the constructs. The scaffolds were seeded using 20×10⁶ cells and cultured for a total of 5 weeks after seeding. The error bars represent standard errors from triplicate bioreactors. Medium GAG data for the 5-day pre-culture treatment were measured in only one of the triplicate bioreactors and are thus unreplicated.