For rapid AAV identity testing method development triplicate injections of baculovirus/Sf9 derived AAV2, AAV5, AAV8 and AAV9 serotypes (Virovek, Hayward, CA, USA) were separated using the HILIC-MS parameters described in Section 2.4. Separations were performed at a column temperature of 45°C and with 15K MS resolution. The scan range was m/z 867-2500. Identification of the VPs for each AAV serotype was performed in BPF using the method parameters outlined in Section 2.8. An 'MS Quantitative' processing method was created within Chromeleon so that full-length protein deconvolution of all injections run in Chromeleon could be performed. Workbooks containing the identifications were generated as described in Section 2.8 and imported into the Chromeleon MS Quantitative method. All parameters were left as is except for the following: In the chromatogram parameters the time limit was set from 13.00 min to 28.50 min. In the source spectra parameters, the RT range was set from 13.00 min to 28.50 min, the merge tolerance was set to 10 ppm, and the min number of detected intervals was set to 10. Data processing parameters in Chromeleon were then optimized to enable the correct identification of each serotype without other serotypes generating false identifications (see Table for optimized data processing parameters). Method validation was performed by applying the developed processing method to triplicate injections of HEK293 cellderived AAV2 sample run in the same sequence as the Sf9-derived AAVs as well as the HEK293 derived AAV2 samples used for VP separation in Section 2.4, which were run in a later sequence.