Tea-bag method

In 1985 Houghton introduced his tea bag method for the rapid solid phase multiple peptide synthesis. In this technique the beads are contained within a porous polypropylene bag. All the reactions, including deprotections, are... 

The tea bag method is very practical. It does not require any special tools, except a sealing device. A number of mesh materials of different porosity are available from Spectrum Medical Industries, Inc. Almost all commercially available resins can be used as long as the size of the beads is larger than the mesh size. The scale of the synthesis is easy to control by the size of the packet chosen to contain the desired amount of a polymer support. The multiple synthesis can be carried out manually or on a synthesizer. 

A convenient arrangement of a sacrificial selenium cathode is the tea bag method, in which a graphite cloth bag is filled with selenium pearls [143]. Other forms of sulfur or selenium electrodes have been described [144]. 

The water content of superabsorbent polymers is usually measured by a tea bag method as follows The dried copolymers are put into a tea bag made of nonwoven fabric. Then they are soaked into excess deionized water or salt solutions for 24 hr at desired temperature. After the tea bag containing polymers are soaked in aqueous solution, the water unabsorbed into gels is removed by placing the tea bag in air for a... 

In the so-called tea-bag method, originated in 1984 by Houghten et al. [14] for multiple peptide synthesis, the split-pool protocol occurs batchwise on 15 x 22 mm polypropylene mesh packets with pm-sized pores known as tea bags, sealed with resin beads for solid-phase synthesis. This method offers the advantage that a greater quantity of each compound of the library is available at once (up to 500 pmol), which is sufficient for a complete biological and structural characterization. Furthermore, the structural identity of... 

Houghten et al. described the tea-bag method for multiple peptide synthesis (Proc. Natl. Acad. Sci. USA, 1985, 82, 5131)... 

As so often happens in science, there is some debate about the primacy of the discovery of combinatorial chemistry. After all, it is almost certain that Carl Wilhelm Scheele was the first to discover oxygen (ca. 1771-72) but the discovery was made independently in 1774 by Joseph Priestley who published first. Similarly, Arpad Furka (1931- ), at the Eotvos Lorand University in Budapest, first described the concept that would later be called combinatorial chemistry in a document notarized in May 1982. A Ph.D. thesis by his smdent on this topic was completed in 1987 and presented at conferences in Prague and Budapest in 1988 (a year before the fall of the Berlin Wall and the end of the cold war). His work first appeared in a refereed journal in 1991. In 1984, H. Mario Geysen (1944— ) at Glaxo Wellcome in North Carolina published research that employed combinatorial chemistry. In that year, Richard A. Houghton (1946- ) started the nonprofit Torrey Pines Institute for Molecular Studies and developed the tea bag method of combinatorial chemistry. 

Tea bag method The superabsorbent polymer is placed in a nonwoven cloth bag, then it is immersed in aqueous solution, and finally weighed after removing the nonabsorbed water... 

Each measurement method has different characteristics (1) the tea bag method is easy and can be widely used (2) the error of the filtration method is relatively large and (3) the centrifugal method can easily plug up the screen. Using these characteristics and the results of inquiry, the tea bag method was chosen. 

This standard specifies the test method of water uptake of superabsorbent polymers using the tea bag method. 

Depending on the type of superabsorbent polymers, measurement of the rate of water absorption is possible using the tea bag method and the DW method. 

Fig. 4(a) Absorption ratio of the aqueous solution of electrolytes (the tea bag method, 30 min immersion). 

Sandwich sheet and large amount of cotton-like pulp Small amount (l-2g) (1) The amount of free swelling is large as measured by the tea bag method... 

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