Today, we will introduce a liposome hand extruder provided by Genizer. It is primarily used for removing particles and sediment from products, as well as reducing the particle size of liposomes and emulsions for sterile filtration. This extruder is suitable for small-volume applications in the experimental stage, and it is operated manually. By pushing the syringe plunger on both sides, a certain external extrusion force is created, forcing the sample to pass repeatedly through the polycarbonate membrane with defined pore sizes. Eventually, the sample is extruded to a uniform size ranging from 20nm to 400nm.

First, let's take a look at the structure of this extruder, This is filter chamger, all its body parts are made of sanitary 316L stainless steel. screw cap, metal body, track-etched membrane, gas-tight syringe,  stabilizer block,

Next, I will show you the assembly steps. First, insert the micron pore plate into the O-ring, then place the assembly into the groove of the filter chamber with the dull side facing up. Install one of the filter chambers into the metal body, then tighten the screw cap. Take out the other filter chamber, use a tweezer to take a piece of track-etched membrane and place it over the filter chamber. The membrane should be flat with no wrinkles or bubbles. And wetting the membrane can be benefitial during the placement process. Install this filter chamber into the metal body and screw on the other cap. take care not to move the membrane. Tighten the screw cap by hand to avoid leakage until you feel a significant resistance. Finger tight should be enough.

Use a syring to draw 1ml of sample and screw it to one side of the metal body, then screw the other syringe to the opposite side. Now, let's open the top cover of the stabilizer block. Place/ Insert the whole/entire assembly into the grooves of the stabilizer block. Put the top cover on. and tighten the nuts to secure it in place. Now the Handextruder is fully assembled.

Now let's move to the sample preparation. Let's start by pushing the plunge of syringe containing the sample to begin the extrusion process.  Pls take care to increase the force evenly and slowly as the housing of the extruder is made of glass. Keep the force direction straight along the syringe to avoid any cracking or damage to the glass.

If the particle size of the sample is too large to be extruded, we recommend starting with a membrane with larger pore sizes before moving to smaller ones. After completing one extrusion in a single direction, you can continue extruding from the other side until the particle size meets the desired requirements. Typically, it may take more than 10 passes to achieve the desired size.

It's best to try several times in the early experimental stage to develop the best solution.  As you can see, the sample becomes  more uniform and transparent after extrusion.