I could recommend the NanoSizer Liposome Mini Extruders from T&T Scientific. These extruders use polycarbonate track-etched membranes. Each NanoSizer Mini Extruder is fully assembled and ready to use (no assembly = save time)
Plus, NanoSizer extruders are single-use: this means no cleaning and no contamination.
*Request FREE Samples* www.ttscientific.com
50nm, 100nm, 200nm, 400nm, and other common (or custom) sizes available