Ammonium acetate nh4ac

Bovine serum albumin (BSA, 66 kDa) was obtained from Sigma-Aldrich (Saint-Louis, MO). Ammonium acetate (NH₄Ac) was purchased from Fisher Scientific (Pittsburgh, PA). BSA solutions were analyzed at two concentrations (i.e., 2 μM and 25 μM in 100 mM aqueous NH₄Ac). Low concentration Tuning Mix standard (G1969-85000) was used for mobility and mass calibration purposes and obtained from Agilent Technologies (Santa Clara, CA).

Details on HMGA2 expression and purification have been previously reported.^{37 (link)} A 22-nt (DNA₂₂, 6.6 kDa) and a 50-nt (DNA₅₀, 15.3 kDa) AT-rich DNA sequence (Figure 1b) were purchased from Eurofins Scientific (Luxembourg City, Luxembourg). These DNA hairpins contain a base pair stem and an AT-rich region in the middle of the stem. Hoechst 33258 was obtained from Sigma-Aldrich (St. Louis, MO). Ammonium acetate (NH₄Ac) was purchased from Fisher Scientific (Pittsburgh, PA). Solutions of HMGA2 alone or in complex with DNA (1:1 ratio) and DNA/HOE (1:1:4 ratio) were analyzed at a concentration of 10 μM in 100 mM aqueous NH₄Ac for native conditions. A low-concentration Tuning Mix standard (G1969–85000) was used to calibrate the TIMS instrument and obtained from Agilent Technologies (Santa Clara, CA).