China Sperm Centrifuge for IVF & IUI Laboratory – KETHINK

Density Gradient Centrifugation Principle

The principle of density gradient centrifugation is that normal sperm and abnormal sperm, immobilized sperm and other cell components in semen have differences in motility, trajectory, and buoyancy density. The ability to run in a density gradient solution column is also different. After centrifugation the various components in the semen reach equilibrium in the density gradient solution column and stay at their respective isobuoyancy density points, so as to achieve classification of normal sperm.

Discontinuous density gradient centrifugation is a more commonly used method at present, that is, before centrifugation, solutions of different densities are layered to form a discontinuous density gradient solution column. It is believed that the discontinuous density gradient centrifugation can recover high-quality sperm, and the buoyancy density can protect the sperm from the damage of centrifugal force to a certain extent. It has been confirmed that, compared with the upstream method, the density gradient centrifugation method can recover more sperm with normal morphology, and significantly increase the vitality and in vitro viability of the sperm. Especially for people with severe semen abnormalities (small, weak, teratozoospermia, etc.), it can greatly improve the sperm recovery rate.

Puresperm Density Gradient Centrifugation Process

PureSperm is an oxidized silica gel solution coated with HEPES-buffered hydrophilic silane. The two-layer density gradient centrifugation method can effectively separate motile sperm from dead sperm, white blood cells and other mixed components in semen.

Sperm Sorting via Centrifuge Steps:

• 1. Take 2mL 80% PureSperm solution and add it to the bottom of a 15mL centrifuge tube, and then slowly add 2mL 40% Pure-Sperm solution along the wall of the tube. Be careful not to mix, there should be a clear interface between the two liquids;
• 2. Add slowly on the surface of the two liquids to have liquefied 2ml of seminal fluid, and pay attention to keep the interface between it and 40% PureSperm solution clear;
• 3. Centrifuge at 300g for 20min at room temperature;
• 4. Remove the supernatant, pipette the pellet into another test tube containing 5ml culture medium, mix well, and centrifuge again at 200g for 10min;
• 5. Remove the supernatant, add the culture solution, adjust the sperm concentration to 1×105～3×105/mL, and place it in a 37℃5%CO2 incubator for later use.