Akta fplc 900 system

The Qβ-based VLPs (Qβ, QβApoB, QβCETP, and QβPCSK9) were characterized as previously described^{[29 (link)]} using fast protein liquid chromatography (FPLC), transmission electron microscopy (TEM), dynamic light scattering (DLS), sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and agarose gel electrophoresis. The Qβ VLPs concentration was determined by measuring the total protein using a Pierce BCA assay kit (Thermo Fisher Scientific). FPLC was performed using an AKTA-FPLC 900 system fitted with Superose 6 Increase 10/300 GL columns (GE Healthcare) using PBS as the mobile phase at flow rate 0.5 mL/min. TEM images were acquired on a FEI Tecnai Spirit G2 Bio TWIN transmission electron microscope. Samples were mounted on 400-mesh hexagonal copper grids and stained with 2% (v/v) uranyl acetate. DLS was carried out on a Malvern Instruments Zetasizer Nano at 25 °C in plastic disposal cuvettes. SDS-PAGE was performed under reducing conditions on NuPAGE 12% Bis-Tris protein gels [Thermo Fisher Scientific] at 120 mV for 35 min. and stained with Coomassie Brilliant Blue. Agarose gels (0.8% (w/v) in TAE buffer) were pre-stained with Gelred™ Nucleic Acid Gel Stain [GoldBio] and samples ran under non-reducing conditions at 100 mV for 30min. The gel images were acquired using the ProteinSimple FluorChem R imaging system.