The concentration of the AAV2 sample was determined using a NanoOrange™ Protein Quantitation Kit composed of a 500´ NanoOrange® protein quantitation reagent (Component A), a bovine serum albumin (BSA) standard (Component B), and a NanoOrange® protein quantitation diluent (10´ concentrated). This fluorescence-based assay was utilized due to its high sensitivity enabling the detection of low protein concentrations. Following the instructions provided, 1´ NanoOrange® working solution was prepared by performing a 10´ dilution of NanoOrange® protein quantitation diluent (10´) with purified water producing a 1´protein quantitation diluent subsequently used to perform a 500´ dilution of the 500x NanoOrange® protein quantitation reagent. BSA samples (for generation of protein standard curve) in concentrations of 10, 6, 3, 1, 0.6, 0.3, and 0.1 µg.mL -1 and 2 % vv -1 AAV samples were prepared in 1´ NanoOrange® working solution (total volume 250 µL per sample). All samples were prepared in triplicate. Prepared samples were incubated at 95°C for 10 min in the dark and then allowed to cool to room temperature in dark for 30 min. 200 µL of each sample was transferred to a 96 well plate and read using a fluorescence plate reader with excitation and emission wavelengths of 485 nm and 590 nm, respectively. Concentration was calculated from the resulting assay readings.