X-band EPR spectra of 100 μM PolyA-TAM solution in deoxygenated 10 mM PBS buffer (pH=7.4, room temperature) before and after addition of BSA. Acquisition parameters were as follows: sweep width, 3G; power, 0.2mW; modulation frequency, 100 KHz; modulation amplitude, 0.05G; conversion time, 80 ms; time constant, 163.84 ms; resolution, 1024 pt.