Modifications of Dextran

Experiment Section

Materials

Synthesis of Dextran-Vinyl Sulfone (Dex-VS)

The degree of substitution was modulated as a function of ratio of DVS to OH, reaction time, and temperature. ^1

Procedure

1. 0.1g Dextran polymers were dissolved in 15mL DMSO

2. 0.1/162*0.1*122.17=7.5mg DMAP was added

3. 0.1/162*3*5*118.15g DVS was added

4. Reacted at dark environment for about 8hr

5. Precipitated in ether, than dissolved in DMSO

6. Precipitated in ethanol

7. Put sample in liquid nitrogen or -80°C refrigerator, than freeze-drying

   NMR

   Dex-VS 20/3%

Synthesis of Dextran-Vinyl Sulfone-Polypeptide (Dex-VS-peptide)

Procedure

1. R3H7C 20mg (Mn=1530, TFA=33%, 0.00875mmol) dissolved in 50uL DI water
2. TCEP 10uL (200mM, 50mg/mL) added, adjusted pH=7.0
3. Dex-VS (20k, 40%) x mg dissolved in 100uL DI water were added
4. Reacted at 45°C for 48h
5. Dialysis, than freeze-drying

x/(Mn of Dex-VS)*(Mn of Dex)/(Mn of one unit of Dex)*2=0.00875mmol

[^2]: Conditions vary with different kind of polypeptides