The HBS-P+ Buffer (HEPES Buffered Saline with Surfactant P20) is a variant of HEPES Buffered Saline, useful in SPR (Surface Plasmon Resonance) protocols. This reagent is formulated at a pH of 7.4 and can be used to prime in-unit pumps within SPR devices. The HBS-P+ solution is useful in assessing binding characteristic and biochemical dynamics between analytes. This solution is formulated at a 1X concentration.