Fig 1: ZnO protein adsorption after incubating ZnO micro- and nanosized particles with human plasma. (A): Total protein adsorbed. (B): SDS-PAGE electrophoresis. ZnO particles (10 mg/mL) were incubated with human plasma for 30 min and then centrifuged and washed with a solution of sucrose 0.7 M in PBS. The protein extracted (18 µg) was finally run by using a Mini-PROTEAN Tetra Cell unit (Bio-Rad, Hercules, CA, USA). The slab gel consisted of 7.5% polyacrylamide resolving gel and 5% polyacrylamide stacking gel. Electrophoresis was carried out for 10 min at 60 V and then at 200 V. Protein bands were stained with Coomassie Blue R-250 with gentle shaking and destained with a mixture of 7.5% methanol and 10% acetic acid. The molecular weight of the membrane proteins was estimated from the molecular size marker (10–250 kDa). Lane 1: human plasma; lanes 2–4: first supernatant obtained from micro-, 100 nm, and 50 nm ZnO samples after centrifugation, respectively; lane 5: pellet from ZnO microparticles; lane 6: pellet from 100 nm ZnO particles; lane 7: pellet 50 nm ZnO particles; lane 8: molecular weight marker.