Cell fractionation of cellular components using Percoll a synthetic, colloidal solution of polyvinylpyrrolidone coated silica, specifically designed for sedimentation centrifugation. Percoll becomes a simple matter to establish a linear density gradient. Organelle separations are much easier to accomplish on Percoll density gradients than on sucrose gradients. - [Read Equilibrium Density Gradient Percoll Protocol]
Protocol for the isolation of Arabidopsis nuclei and measurement of gene transcription rates using nuclear run-on assays. Plant materials are ground in hexylene glycol-based buffers and highly enriched nuclear fractions are obtained using Percoll density gradients. Standard and small-scale protocols are presented, along with a tested method for nuclear run-on assays. The entire process may be completed within 3 days. - [Read Isolation of Arabidopsis Nuclei and Measurement of Gene Transcription Rates Protocol]
Although Percoll gradients were able to provide a purified sporocyst fraction, because these particles do not all band in a discrete manner in such gradients, they were unable to provide a simultaneous isolation of a pure oocyst wall fraction. Gradients formed from this protocol on the other hand are able to provide purified sporocysts and oocyst walls in the same gradient. - [Read Purification of Oocyst Walls and Sporocysts from Toxoplasma gondii Protocol]