Fig. 7.

Vesicle detection using antibody immobilised beads. PS-COOH beads (1 µm) conjugated with Aquaporin-1 (Aqp1) antibody incubated with BD21 vesicles without Aqp1 protein showing no binding of vesicles a–c. The specific binding of BD21 vesicles containing Aqp1 protein on the anti-Aqp1-beads as confirmed by fluorescence from RBOE dye in vesicles in e. Fluorescence from Alexa-fluor 488-labelled secondary antibody further confirmed the presence of Aqp1 in vesicles bound to the anti-Aqp1-beads f. Scale bar is 10 µm. g Schematics showing the detection based on the change in size due to the binding of vesicles onto the antibody-conjugated beads. The buffer media used here is 0.1 × PBS solution. h The detection of vesicle concentrations of 3.75–375 µg mL⁻¹ was performed with four sets of samples (n = 4) with SD as the error bars. Independent two-sample t-test is used for the statistical analysis where *p < 0.05, **p < 0.01, and ***p < 0.001