Soil pH Soil pH Soil pH is a measure of the acidity or basicity (alkalinity) of a soil. pH is defined as the negative logarithm (base 10) of the activity of hydronium ions ( or, more precisely, ) in a solution. In soils, it is measured in a slurry of soil mixed with water (or a salt solution, such as 0.01 M ), and normally falls between 3 and 10, with 7 being neutral. Acid soils have a pH below 7 and alkaline soils have a pH above 7. Ultra-acidic soils (pH < 3.5) and very strongly alkaline soils (pH > 9)
Immobilized pH gradient gradient instability and poor sample loading capacity associated with carrier ampholyte pH gradient. Commercial precast IPG gels are available. Immobilized pH gradient Immobilized pH gradient (IPG) gels are the acrylamide gel matrix co-polymerized with the pH gradient, which result in completely stable gradients except the most alkaline (>12) pH values. The immobilized pH gradient is obtained by the continuous change in the ratio of "Immobilines". An "Immobiline" is a weak acid or base defined by its pK value. Immobilized pH gradients (IPG) are made by mixing two kinds of acrylamide mixture, one with Immobiline having acidic buffering property and other