FIG. 1.

Sodium heparin increases the adherence of S. aureus to polystyrene. A. Dose response. Serial dilutions of sodium heparin were added to cultures and biofilms were allowed to form for 16 h, at which time nonadherent cells were removed by vigorous washing. Adherent cells were stained with crystal violet. Spectrophotometric analysis of solubilized crystal violet is shown as a function of increasing sodium heparin concentration in U/ml. B. Biofilm formation in response to various charged molecules and glycosaminoglycans. Microtiter biofilms were analyzed as above, and significant differences from the saline-alone control are shown with an asterisk (P < 0.01). C. Adherence kinetics. The effect of sodium heparin (1,000 U/ml, 10% vol/vol) or saline (10% vol/vol) upon biofilm formation was assessed over time. A photograph of crystal violet-stained biofilms is shown at the top of the panel and spectrophotometric results are charted with respect to time at the bottom of the panel. D. Growth curve. The effect of heparin (1,000 U/ml) on planktonic growth in TSB plus glucose was analyzed and plotted versus time.