P407-FA was synthesized via a previously reported method with modifications [28 (link)]. Firstly, 87.58 mg (0.20 mmol) of FA was dissolved in 5 ml dried DMSO and added to a one-neck flask. Then, 35.32 mg (0.22 mmol) of CDI was added to the solution, and the reaction was stirred for 24 h at room temperature in the dark, then we added 0.62 g (0.05 mmol) of P407 which had been previously dried overnight in a vacuum and the reaction was allowed to proceed in the dark for 1 day at room temperature. After the reaction was completed, the mixture was dialyzed for 5 d in a dialysis bag with a molecular cut off of 3000 to remove free FA. P407-FA was recovered via lyophilization. The resulting product was dried in a vacuum oven for 2 d and stored in a dry box, yielding 56% w/w of product.
Prepared P407-FA was characterized by 1H-NMR and differential scanning calorimetry (DSC-60; Shimadzu Corporation, Kyoto, Japan). 1H-NMR spectrum of P407-FA was recorded on a Gemini-200 spectrometer (Varian, CA, USA) using DMSO-d6 as the solvent. UV-Vis spectra were acquired using a UV-1601 spectrophotometer (Shimadzu Corp., Kyoto, Japan) to determine the degree of conjugation of FA by measuring the absorbance at 360 nm.
Prepared P407-FA was characterized by 1H-NMR and differential scanning calorimetry (DSC-60; Shimadzu Corporation, Kyoto, Japan). 1H-NMR spectrum of P407-FA was recorded on a Gemini-200 spectrometer (Varian, CA, USA) using DMSO-d6 as the solvent. UV-Vis spectra were acquired using a UV-1601 spectrophotometer (Shimadzu Corp., Kyoto, Japan) to determine the degree of conjugation of FA by measuring the absorbance at 360 nm.
