Determinants of water proton T1 in blood serum.

Water proton T1 (10.7 MHz; 7 degrees C) and albumin and globulin contents were measured in the blood serum of 30 normal volunteers. The T1 relaxivity of serum albumin and globulin (i.e., the change of water relaxation rate 1/T1 per concentration unit) was determined in pure albumin and globulin solutions. It is shown that more than 90% of the serum relaxation rate 1/T1 is due to the proteins, making T1 a nonspecific blood parameter. In addition five pathological serum samples were examined, explaining clearly why serum T1 is not a clinically useful measurement.