The Bullet Blender uses homogenization beads to strike and grind your samples. You may choose from a variety of beads suitable for a wide array of samples. The general rules of thumb for choosing the correct beads for your sample are: · Choose beads with higher densities for tougher samples · Choose smaller sizes for tiny samples and cell culture · Choose larger sizes for tough samples and special applications General Usage Guidelines · Use a volume of beads that is at least half the volume of liquid in the tube. Using too few beads may lead to poor homogenization. Use a size of bead proportional to the size of your sample. For very small samples, such as cell culture or tiny pieces of tissue, use our smallest beads (0.2mm or below). For large chunks of tissue, beads 1.0mm or greater may be needed (Beads larger than 3.5mm are not recommended for microcentrifuge tubes). · For tougher tissue, use denser beads (e.g. zirconium oxide and stainless steel). With soft tissue you can use less dense beads (e.g. glass and zirconium silicate). · For isolation of organelles, use larger beads (0.5mm or larger for cell culture, 1.0mm or larger for tissue) Bead Sample Packs are convenient for method optimization, or for labs that homogenize several different sample types. Sample packs come with a 10 mL tube of each type of included bead, EXCEPT the BSP-50B for 50 mL tube Bullet Blender models, which comes with 20 mL of each included bead type. Bead Composition During the vigorous agitation of the homogenization process, denser beads have more momentum, resulting in more energetic impacts with the samples. Dense beads, like those composed of stainless steal, can homogenize tougher samples. Such powerful beads do, however, cost more to manufacture. Another consideration for optimal homogenization is the size of the bead. Finally, alternative bead shapes can be used to further improve homogenization of tough samples. Stainless steel beads are available with a ridge. These "UFO" shapes are useful for slicing and grinding tough samples. Types of Beads Stainless Steel (density = 7.9 g/cc) ~80 mL/pound Stainless steel beads can be used for the homogenization of tough samples or for special applications such as bacterial isolation. Bulk Stainless Steel Beads are sold by the pound (0.45 kg). UFO Beads are sold by the 50 mL package. RNAse-free Stainless Steel Beads are sold by the 4 mL package. Zirconium Oxide (density = 5.5 g/cc) ~120 mL/pound Zirconium oxide beads can be used for the homogenization of medium consistency samples and tougher-to-lyse cell suspensions. Bulk Zirconium Oxide Beads are sold by the pound (0.45 kg) RNase-free Zirconium Oxide Beads are sold by 4 mL package Zirconium Silicate (density = 3.8 g/cc) ~180 mL/pound Zirconium silicate beads can be used for the homogenization of medium-soft samples. Bulk Zirconium Silicate Beads are sold by the pound (0.45 kg) Glass (density = 2.5 g/cc) ~300 mL/pound Glass beads are used for the homogenization of soft tissue and easy-to-lyse cell suspensions. Bulk Glass Beads are sold by the pound (0.45 kg) RNAse-free Glass Beads are sold by the 4 mL container Bead Sample Packs Sample packs of different bead types. Great for methods development or for labs that work on a wide variety of samples.