Fig. 2. Binding selectivity and Bet v 1-binding capacity of NPs. (a) Schematic representation of the experimental setup. (b) SDS-PAGE of birch pollen extract (BPE) incubated with SiO₂ NPs. Lane M: protein marker; lane 1: BPE bound to MSNPs; lane 2: BPE only; lane 3: BPE bound to NSNPs. (c) Immunoblot using anti-Bet v 1 monoclonal mouse antibodies for the detection of Bet v 1. Lane M: protein marker; lane 1: BPE bound to MSNPs; lane 2: BPE only; lane 3: BPE bound to NSNPs; and lane 4: recombinant Bet v 1. (d) Intensity of bands 1–5 of BPE bound to SiO₂ NPs relative to the intensities of BPE only bands. (e) Binding capacity of SiO₂ NPs for recombinant Bet v 1 (e.g., 10% values refer to 10 μg mL⁻¹ protein per 100 μg mL⁻¹ NPs).