Narrow and Ultranarrow pH Gradients

We deRne the gradients (in the gel slab) from 0.1 to 1 pH unit as ultranarrow and narrow gradients, respectively. Within these limits one can generally work on a 'tandem' principle, i.e. choosing a 'buffering' Immobiline (e.g. a base or an acid), having its pK within the desired pH interval, and a 'non-buffering' Immobiline (e.g. an acid or a base), having its pK at least 2 pH units removed from either pHmin or pHmax of the pH range. The latter will therefore provide equivalents of acid or base, respectively, to titrate the buffering group, but will not itself buffer in the desired pH interval. For these calculations one

Figure 4 Hypothetical structure of an Immobiline gel and mechanism of the focusing process. The acrylamido acid and basic groups are shown grafted on the polyacrylamide matrix. Two proteins are shown migrating in the gel at the times t = 0, at t = 1 and finally at the steady-state, where they reach they respective p/values (p/ and p/2) as points of zero net charge (by permission of LKB ProdukterAB).

Figure 4 Hypothetical structure of an Immobiline gel and mechanism of the focusing process. The acrylamido acid and basic groups are shown grafted on the polyacrylamide matrix. Two proteins are shown migrating in the gel at the times t = 0, at t = 1 and finally at the steady-state, where they reach they respective p/values (p/ and p/2) as points of zero net charge (by permission of LKB ProdukterAB).

can resort to modified Henderson-Hasselbalch equations and to rather complex nomograms or simply adopt tabulated recipes, 1 pH unit wide, which start with the pH 3.8-4.8 interval and end with the pH 9.5-10.5 span, separated by 0.1 pH unit increments (58 such recipes have been tabulated). If a narrower pH gradient is needed this can be derived from any of the 58 pH intervals tabulated by a simple linear interpolation of intermediate Immobiline molarities.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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