The FOCUS™ Cell Fractions line of products are optimized specifically for downstream applications such as isoelectric focusing and 2D electrophoresis.
The FOCUS™ ‐Cytoplasmic & Nuclear Protein Extraction Kit was developed for the enrichment of cytoplasmic and nuclear fractions from cultured cells and tissues for proteomic as well as expression and transport studies. Supplied with a strong chaotropic extraction buffer to solubilize both cytoplasmic as well as nuclear proteins for 2D gel analysis. The nuclear and cytoplasmic protein preparations are suitable for IEF & 2D gel electrophoresis.
FOCUS™ Global Fractionation Kit is specifically designed for a simple, rapid and highly reproducible method for fractionation of various classes of cellular proteins. This kit allows fractionation of soluble and insoluble proteins. The insoluble protein fraction may be further fractionated into various classes of membrane proteins, such as mildly hydrophobic membrane proteins, highly hydrophobic trans‐membrane proteins, and membrane proteins rich in cholesterol, glycolipids, and glycosyl‐phosphitidylinositol (GPI).
FOCUS™ Glycoprotein is an optimized method for enrichment and removal of glycoproteins from complex protein samples. FOCUS™ Glycoprotein kit is based on lectin binding for specific glycoproteins with terminal α‐D mannosyl and α‐D glycosyl proteins. The kit is provided in spin column format containing Concanavalin A (Con A) Agarose, which consists of Con A coupled to agarose beads. Concanavalin A (Con A) Agarose has the capacity to bind and immobilize 15‐30mg glycoproteins. Column bound glycoproteins are eluted with a set of three rapid elution buffers.
FOCUS™ Membrane Proteins Kit is specifically designed for a simple, rapid and highly reproducible method for preparation of membrane or hydrophobic proteins from biological samples for 2D‐gel analysis or other applications. This kit does not require the use of difficult to prepare gradients or the use of expensive ultracentrifuge equipments. This kit consists of reagent solutions consisting of non‐ionic detergents, which allows isolation of membrane by temperature dependent phase partition [1‐2]. Protein sample is mixed, homogenized or suspended in the membrane extraction buffer. After a brief incubation at 35‐37°C, the sample is centrifuged which results in separation of a membrane (hydrophobic) protein rich layer. Proteins anchored to the membrane or proteins containing one or two trans‐membrane regions are extracted into the membrane rich protein layer with the efficiency higher than 50%. Lower efficiency may be obtained with more complex membranes. The membrane (hydrophobic) preparation is suitable for most applications including SDS‐PAGE, Western blotting, 2D‐gel analysis, etc. The kit is suitable for 50‐100 preps (depending on sample size).
FOCUS™ Mitochondria Kit enables the fast and easy isolation of enriched mitochondrial fractions from animal cells and tissues. The majority of the isolated mitochondria obtained from this kit contain intact inner and outer membranes. This kit contains reagents for processing 50-80 preparations of 20 million cultured mammalian cells or 20-30 preps of 50-100mg tissue. The number of preparations varies depending on the protocol, preparation size and cell or tissue type.
Signal Proteins: Caveolin‐enriched membrane proteins and membrane proteins rich in cholesterol, glycolipids and glycosyl-phosphitidylinositol (GPI) are generally not soluble in a wide range of non-ionic detergents. These proteins are believed to be involved in directing intracellular membrane traffic. FOCUS™‐Signal Proteins Kit is designed to fractionate caveolin‐enriched membrane proteins, proteins rich in cholesterol, glycolipids, GTP‐binding, and GPI‐linked proteins. The extraction method involves solubilization and removal of hydrophilic proteins as well as hydrophobic (membrane) proteins soluble in non‐ionic detergents. Signal Protein Extraction Buffer is a proprietary formulation of non‐ionic detergents designed to efficiently extract and remove soluble proteins, leaving signal proteins as detergent insoluble fraction. After fractionation, the signal protein fraction is solubilized in FOCUS™ Protein Solubilization Buffer supplied with the kit.
FOCUS™ Soluble and Insoluble Kits are optimized for the selective preparation of soluble (hydrophilic) and insoluble (hydrophobic) proteins from mammalian tissues and cells, plants, yeast, bacteria, and other biological samples. The kit comes with reagents necessary for fractionation of soluble and insoluble fractions, including a strong chaotropic extraction buffer to solubilize difficult proteins.
FOCUS™ SubCell Kit enables the fast and easy enrichment of nuclear, mitochondrial, membrane and cytosolic fractions from animal cells. The mitochondrial fraction can be subsequently separated into heavy and light fractions by gradient centrifugation. An additional step is included to minimize contaminations of the nuclear fraction by cytoplasmic elements (see schematic on the right). The majority of mitochondria, isolated with this kit, contain intact inner and outer membranes. FOCUS™ SubCell is suitable for cultured animal cells and can be adapted for animal tissues.