Lonza LAL reagent should be handled gently. After reconstitution, the contents of the vial will easily go into solution by either gently inverting or swirling the vial. Vortexing or vigorously shaking the reconstituted LAL reagent will cause it to foam. Reconstitute a few minutes prior to use, and let the vial sit on the bench top undisturbed until use. Never vortex your reaction vessel after adding the LAL.