Remarks upon the effect of temperature and dextran coated charcoal on buffer pH in steroid receptor assays

Phosphate and TRIS buffers of low molarity commonly used for steroid receptor assays were studied for their pH stability. Increased temperature from 0-37 degrees C lowers the pH of TRIS buffer, while phosphate buffer remains approximately constant. Addition of dextran and charcoal may change the pH unacceptably, depending on the charcoal quality.