Buffer Solution pH 4.0 (0.02), is supplied by HiMedia. It is available in the form of a colourless solution with a pH in the range of 3.8 to 4.2. The pH of a solution is the most common routinely performed measurement in a molecular biology laboratory. As the pH of any solution affects all chemical and biochemical reactions, it is very important to have a reliable and accurate measurement of it. The pH-meters are used to measure the pH of any solution. It functions by measuring the voltage developed between two electrodes immersed in the sample and compare that value to a calibration derived from the same electrode pair and known standards. These standard buffer solutions must be accurate and reliable and are used for pH meter calibration. A properly calibrated pH meter gives more precise and accurate readings. It is advisable to store this product between 2-8C.

Buffer Solution pH 4.0 ( 0.02) is used as a standard buffer in Molecular Biology. It is mainly used as a calibration buffer for the pH meters. A buffer solution is one which resists changes in pH when small quantities of an acid or an alkali are added to it. An acidic buffer solution is simply one which has a pH less than 7. Acidic buffer solutions are usually made from a weak acid and one of its salts, often a sodium salt. Buffer Solution pH 4.0 ( 0.02) is used as a standard buffer for the calibration of pH meters. This pH buffer solution calibrates the pH meter to a pH of 4.0 at 25C.