Figure 5.

Time series of xy optical sections recorded by using multiphoton excitation during uptake of unlabeled lysozyme into SP Sepharose FF with a ×40 oil objective, with the focal depth approximately at the center of the particle. The superficial velocity through the bed was 360 cm/h and the lysozyme concentration was 1.8 mg/ml. The image contrast was enhanced by using Scion image software because of the low signal-to-noise ratio. The particle diameter for this experiment was 87 μm, compared with 105 μm for the lysozyme-Cy5 case, explaining the slightly faster uptake in this case. (Magnifications: ×250.)