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McIlvaine buffer is a buffer solution composed of citric acid and disodium hydrogen phosphate, also known as citrate-phosphate buffer. It was introduced in 1921 by the United States agronomist Theodore Clinton McIlvaine (1875–1959) from West Virginia University , and it can be prepared in pH 2.2 to 8 by mixing two stock solutions.
Total ionic strength adjustment buffer (TISAB) is a buffer solution which increases the ionic strength of a solution to a relatively high level. This is important for potentiometric measurements, including ion selective electrodes , because they measure the activity of the analyte rather than its concentration.
In biochemistry and molecular biology, saline-sodium citrate (SSC) buffer is used as a hybridization buffer, to control stringency for washing steps in protocols for Southern blotting, in situ hybridization, DNA Microarray or Northern blotting. 20X SSC may be used to prevent drying of agarose gels during a vacuum transfer.
The speciation diagram shows that solutions of citric acid are buffer solutions between about pH 2 and pH 8. In biological systems around pH 7, the two species present are the citrate ion and mono-hydrogen citrate ion. The SSC 20X hybridization buffer is an example in common use. [23] [24] Tables compiled for biochemical studies are available. [25]
Buffer capacity falls to 33% of the maximum value at pH = pK a ± 1, to 10% at pH = pK a ± 1.5 and to 1% at pH = pK a ± 2. For this reason the most useful range is approximately p K a ± 1. When choosing a buffer for use at a specific pH, it should have a p K a value as close as possible to that pH.
It is a defined, selective and differential medium that tests for an organism's ability to use citrate as a sole carbon source and ammonium ions as the sole nitrogen source. After citrate enters a cell through citrate permeases, citrate lyase cleaves it into acetate and oxaloacetate, which is further broken down into carbon dioxide and pyruvate ...
(B) Dependence of Tm1 and Tm2 on the pH of the buffer of all tested conditions. NanoDSF is a type of differential scanning fluorimetry (DSF) method used to determine conformational protein stability by employing intrinsic tryptophan or tyrosine fluorescence , as opposed to the use of extrinsic fluorogenic dyes that are typically monitored via a ...
The Gran plot is based on the Nernst equation which can be written as = + {+} where E is a measured electrode potential, E 0 is a standard electrode potential, s is the slope, ideally equal to RT/nF, and {H +} is the activity of the hydrogen ion.