Table 1.

Assay of dye leaching from test surface in PBS. Mean and standard deviation for absorbance at 590 nm and 651 nm are shown (n = 3).

Sample	Absorbance of PBS at 590 nm	Absorbance of PBS at 651 nm
PBS containing test surface kept in light	0.003 (0.002)	0.003 (0.004)
PBS containing test surface kept in darkness	0.013 (0.006)	0.010 (0.004)