Fig. 6. Quantification of l-tyrosine in filtrates obtained from vaccines containing l-tyr (0.7 mg mL⁻¹) and l-tyr + OVA (0.7 mg mL⁻¹ + 70 μg mL⁻¹) formulated in saline, pH 7 ± 0.1. Panels (A) and (B) represent the particulate recovery > ca. 5 μm and <0.1 μm (soluble) respectively. Panel (C) shows the particulate recovery between 5 and 0.1 μm and panel (D) highlights the relative percentage contribution of each fraction to the whole vaccine. Error bars are representative of ±SD of the measurement where n = 5. Data were analysed for statistical significance using a two-tailed unpaired T-test.