Synthesis and Characterization of CPPM Compound

Dimethyl sulfoxide (DMSO) was purchased from Fisher Scientific and DMSO-d6 was purchased from Cambridge Isotopes Laboratory, Inc. PBS Buffer, 10x, pH 7.4, was purchased from Thermo Fisher Scientific, Inc. and diluted to 1x concentration with Milli-Q water. Trifluoroacetic acid (TFA) was purchased from Alfa Aesar and used without further purification. Methanol and dichloromethane were purchased from Fisher Scientific and used without further purification. Additional materials required for the synthesis of the CPPM used in this study, MePh₁₀-b-dG₅, have been previously reported.^{43 (link),44 (link)} Human angiotensin II (#A9525), bradykinin (#B3259), diethylpyrocarbonate (DEPC) (#D5758), imidazole (#I5513), sodium chloride (#S5886), guanidine thiocyanate (GTC, #G6639), and iodoacetamide (#I6125) were all purchased from Sigma-Aldrich (St. Louis, MO). Immobilized TPCK-trypsin (#20230) was obtained from Thermo Scientific (Waltham, MA). Potassium phosphate monobasic (#P285), sodium phosphate dibasic anhydrous (#S374), formic acid (#A117), water (#W7), and acetonitrile (#A998) were obtained from Fisher Scientific (Fair Lawn, NJ). Amicon® centrifugal filters (#UFC501096 & #UFC800324) were from Millipore Sigma (Burlington, MA). Superfolder green fluorescent protein (sfGFP) was expressed and purified by Dr. Francesca Anson using procedure described below.