Fluorescence and bright field images of test and control algae and <i>Daphnia</i>.

<p><b>A</b>. Bright field images of algae taken from test sample, After 24 h incubation with 28 nm fluorescently labeled nanoparticles. <b>B</b>. Fluorescence micrograph of algae from A, imaged with Deep Blue filter cube (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0032254#s4" target="_blank">Methods</a>), here algal cells are fluorescent due to adsorption of fluorescently labeled nanoparticles. <b>C</b>. Bright field images of algae taken from control sample. <b>D</b>. Fluorescence micrograph of algae from C, imaged with Deep Blue filter cube, here algal cells are clearly non-fluorescent. Scale bars, A–D: 10 µm. <b>E</b>. Fluorescence micrograph of <i>Daphnia</i>, taken after 24 hrs incubation with test algae and a light wash through filter. <b>F</b>. Close up of E, nanoparticles can be seen in and on the <i>Daphnia</i>. <b>G</b>. Fluorescence micrograph of control <i>Daphnia</i>, taken after 24 hrs incubation with control algae and a light wash through filter. <b>H</b>. Close up of G, note some auto-fluorescence in the gut and heart and developing offspring, much of which is distributed evenly. Scale bars, E–H: 500 µm.