d) Predict the conformation of the mPEG chains when grafted to the nanoparticle surface. 5. TGA was carried out on a sample of 15 nm Au nanoparticles coated with mPEG-SH (molecular weight 5400) ligands. The measured weight loss after heating to 320C was measured to be 9.9%. a) Calculate the total number of PEG chains per particle b) Calculate the grafting density (in units of nm) of the ligands. c) Calculate the R of the ungrafted mPEG chain. d) Predict the conformation of the mPEG chains when grafted to the nanoparticle surface