Membranes, nitrocellulose

Membrane filtration has been used in the laboratory for over a century. The earliest membranes were homogeneous stmctures of purified coUagen or 2ein. The first synthetic membranes were nitrocellulose (collodion) cast from ether in the 1850s. By the early 1900s, standard graded nitrocellulose membranes were commercially available (1). Their utihty was limited to laboratory research because of low transport rates and susceptibiUty to internal plugging. They did, however, serve a useflil role in the separation and purification of coUoids, proteins, blood sera, enzymes, toxins, bacteria, and vimses (2). 

Specificity of the antisera was assessed by Western blotting. Electrophoretically separated proteins from culture filtrates were transferred to 0.45 fim nitrocellulose membranes. After transfer of proteins, membranes were... 

Houston B, Peddie D (1989) A method for detecting proteins immobilized on nitrocellulose membranes by in situ derivatization with fluorescein isothiocyanate. Anal Biochem 177 263-267... 

The boiled samples are resolved by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) using 4 to 20% polyacrylamide gels, loaded in the following order 3% input —10 fA of eluate (15% of the total volume of the boiled eluate El) —20 fA of eluate (30% E2) —3% supernatant, respectively, and transferred to nitrocellulose membranes (Novex or Bio-Rad). 

Transfer proteins onto a nitrocellulose membrane using any appropriate procedure, including dot blotting the protein solution onto the surface. 

A breakthrough for tissue printing, at least for the botanical sciences, came when Cassab and Varner (3) combined the use of nitrocellulose and antibody technology. They placed sections of a freshly cut soybean seed on nitrocellulose membranes and probed the resulting imprints using specific antibodies. They were able to show that soluble extensin protein is primarily localized in the seed coat and vascular tissues. 

Okra, Hibiscus escuentus L. The immature pods of okra are popular as a vegetable and okra is also used for the ability to thicken soups and stews, and for fiber and oil. Notmuch is known about okra most workers concentrate their research on the chemical composition (26-29) of the mucilaginous materials found in the pod (30) stalk, nutritional properties (31). Research has also been conducted on the developmental properties of the okra seed (32). This paper is the first report of the chemical composition of auxin conjugates in okra pods bound to nitrocellulose membrane. 

Tissue prints on nitrocellulose membranes (Schleicher Schuell) (0.45 pm pore size) were first stained for protein using Ponceau S (Fig. 2A,B) and photographed immediately with T-max 100 black-and-white film. The membranes were then washed in PBS to remove the stain, and incubated for 2 h with shaking in blocking solution. 

Taylor R, Varner JE. The role of calcium in maintaining cell-wall firmness studied by physical printing on nitrocellulose membranes, in Tissue Printing Tools for the Study of Anatomy, Histochemistry, and Gene Expression (Reid P, Pont-Lezica R, del Campillo E, Taylor R, eds.), Academic Press, New York, 1992, pp. 15-17. 

Plant Cells and Tissues Structure-Function Relationships. Methods for the Cytochemical/Histochemical Localization of Plant Cell/Tissue Chemicals. Methods in Light Microscope Radioautography. Some Fluorescence Microscopical Methods for Use with Algal, Fungal, and Plant Cells. Fluorescence Microscopy of Aniline Blue Stained Pistils. A Short Introduction to Immunocytochemistry and a Protocol for Immunovi-sualization of Proteins with Alkaline Phosphatase. The Fixation of Chemical Forms on Nitrocellulose Membranes. Dark-Field Microscopy and Its Application to Pollen Tube Culture. Computer-Assisted Microphotometry. Isolation and Characterization of... 

Antibodies may also be used to determine the presence or identity of soluble antigens by a process known generally as immunoblotting. In a technique known as dot blotting , soluble antigens are applied to a nitrocellulose membrane in the form of dots , antibody is then applied to the membrane, the membrane is washed to remove unbound antibody, and the presence or absence of the antigen is determined by similar means to that employed during immunohistochemistry. 

Another similar technique to Southern blotting is Northern blotting. Here, instead of DNA fragments, mRNA fragments are probed with a labelled cDNA probe after separation by electrophoresis and transfer to nitrocellulose membranes. Northern blotting is used to detect and quantify mRNA from tissue extracts. 

N.C. nitrocellulose membrane. PVDF polyvinylidene fluoride membrane. 

For far Western blotting, native or recombinant proteins are separated by SDS-polyacrylamide gel electrophoresis (SDS-PAGE), transferred to the nitrocellulose membranes and the blotted proteins are... 

GC material was widely modified with conducting (or nonconducting) polymers in order to obtain an improved surface for DNA adsorption and detection. The initial approaches were performed by the physical attachment of nylon or nitrocellulose membranes on GC electrodes [51]. As explained, these membranes were extensively used in classical DNA analysis due to their well-known adsorption properties [33]. Other approaches were performed by the direct adsorption of the polymeric film on the GC surface. Finally, polymeric films were electrochemically grown on the GC substrate. These conducting polymers are particularly promising for the adsorption, but also for inducing electrical signals obtained from DNA interactions. 

Classical approach, 1960s to present Modern era, 1988 to present e.g., nitrocellulose membrane e.g., biochip... 

Membranes cast upon glass slides also fall into the 3D surface category. Most notable are the nitrocellulose-coated FAST slides offered by Schleicher Schuell (S S) BioScience. A cytokine micro-ELISA product xmder the trade name Provision has been introduced in single-slide and 96-well spacing (64 usable wells) formats. It is called FAST Quant (Harvey, 2003). Historically, nitrocellulose membrane has been used for the sequestering of both proteins and nucleic acids. The adaptation by S S of this microporous (0.2-p pores) material cast into a microarray format has been relatively straightforward. 

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