TABLE 1.

Zeta potential measurements for C. parapsilosis and P. aeruginosa^a

Organism and concn (mM)	pH	ζSmolb (103 V)	EMc (108 m2 · [V · s]−1)	ψ0d (103 V)
C. parapsilosis
20	6.81	−5.1	−0.39 ± 0.01	−6.2
40	6.84	−4.5	−0.35 ± 0.18	−3.1
60	6.99	−3.4	−0.26 ± 0.11	−2.1
80	7.01	−6.3	−0.49 ± 0.10	−1.6
100	7.03	−4.7	−0.37 ± 0.10	−1.3
P. aeruginosa
20	6.95	−8.0	−0.62 ± 0.14	−10.3
40	6.98	−6.7	−0.52 ± 0.07	−5.3
60	6.99	−4.4	−0.34 ± 0.08	−3.6
80	7.01	−5.4	−0.42 ± 0.28	−2.7
100	7.01	−3.4	−0.26 ± 0.10	−2.2

^aAll samples were grown at 37°C until the OD₆₀₀ was approximately 0.5 and suspended in MES buffer with varying ionic strength to a cell concentration of approximately 10⁸ cells/ml.

^bZeta potential as calculated from the Smoluchowski equation.

^cAverage electrophoretic mobility of microbial culture (n = 4) with SDs of repeated data sets.

^dSurface potential as calculated from soft-particle DLVO theory; this is equivalent to the zeta potential of the solution (36).