During initial investigations, it was observed that the MS spectrum of the detected VPs appeared to have a bimodal distribution, suggesting the presence of multiple non-native conformational protein states for each VP (Electropherogram of Condition 1 in Figure ) . It has been shown that small quantities of DMSO in aqueous solution can result in intact proteins becoming more compact and thus generating preference for lower charged protein species Here, the BGE containing 4% DMSO solution was prepared by removing 5 mL of BGE from a new 125 mL bottle of Peptides BGE and then adding 5 mL of LC-MS grade DMSO to the bottle of Peptides BGE . The 5 mL of BGE originally removed from the Peptides BGE bottle was stored in a clean glass vial and subsequently used for sample incubation where appropriate. The presence of the 4% DMSO in the sample analysis improved data quality compared to using Peptides BGE as is without adding DMSO. First, the intensity of the peaks in the electropherograms increased in Conditions 2 and 3 compared to Condition 1 (Figure ). It was also noted that the MS spectra had a more traditional bell curve charge distribution for each VP in Conditions 2 and 3 compared to the bimodal distribution in Condition 1 (Figure ). This suggests that the presence of DMSO is reducing the number of conformational protein states for each VP, possibly by causing protein refolding into a more compact protein conformational structure . The presence of fewer, or possibly a single, denatured protein conformational state for each VP directly leads to increased MS signal intensity with the raw signal intensity for each VP increased in Conditions 2 and 3 compared to Condition 1. Processing the raw data with BPF 5.1 further reenforced this observation from the raw MS spectra. As exemplified by acetylated-VP3 ((Ac)VP3) and VP2 in Table , respectively, the most abundant and least abundant proteoforms detected across all three conditions, it is clearly demonstrated that the presence of DMSO enhanced the summed signal intensity, reduced the total number of charge states, and also reduced the charge state distribution range. In BPF, the summed signal intensity represents the sum of the MS signal intensity values from all the raw data files processed. Here, the data shows that the average sum intensity for each VP proteoform increases in the presence of DMSO. For (Ac)VP3 the average sum intensity increases from 2.34 × 10 10 in Condition 1 to 3.54 × 10 10 and 3.35 × 10 10 in Conditions 2 and 3 respectively, while for VP2 it increases from 8.91 × 10 7 in Condition 1 to 3.67 × 10 8 and 3.31 × 10 8 in Conditions 2 and 3 respectively. As previously mentioned, the presence of low percentages of DMSO leads to a preference of lower charged protein species, with the average maximum charge state of (Ac)VP3 dropping from 83.60 in Condition 1 to 66.80 and 66.40 in Conditions 2 and 3, respectively. A similar observation is seen with VP2 as the average maximum charge state drops from 88.60 in Condition 1 to 72.00 and 71.50 in Conditions 2 and 3, respectively. Interestingly, we also see that in the presence of DMSO, there is a slight upward shift at the low-end charge states towards higher charged protein species. For (Ac)VP3 the average minimum charge state shifts from 31.20 in Condition 1 to 37.40 in both Conditions 2 and 3 while for VP2 it shifts from 44.00 in Condition 1 to 48.60 and 49.25 in Conditions 2 and 3, respectively. These results suggest that the potential protein compaction caused by the presence of DMSO results in a consolidation in the number of overall charges states that predominately, but not entirely, favours lower charged species. Similar trends as those discussed above are seen for all the detected VPs (Table ). While no additional components were seen, low abundant proteoforms were detected in greater quantities and with better quality scores (a BPF 5.1 metric for determining identification confidence) in Conditions 2 and 3 compared to Condition 1, with Condition 2 generally providing the best results (Table ).