NWLSS™ Catalase Activity Assay Kit 推荐用于检测存在过氧化氢酶的组织匀浆、细胞裂解液和其他生物液体或提取物中的过氧化氢酶活性的研究。

Hydrogen peroxide (H2O2) is formed in cells by controlled pathways and elicits a broad spectrum of cellular response ranging from mitogenic growth stimulation to apoptosis to necrosis at different concentration levels. Locally intense amounts of H2O2 can also be produced by inflammatory cells to kill pathogens. H2O2 at high concentration is deleterious to cells and its accumulation causes oxidation of cellular targets such as proteins, lipids and DNA leading to mutagenesis and cell death. Removal of H2O2 from cells is therefore necessary for protection against oxidative damage

The enzyme catalase is an endogenous antioxidant present in all aerobic cells helping to facilitate the removal of hydrogen peroxide. The enzyme consists of 4 subunits of the same size, each of which contains a heme active site to accelerate the decomposition of H2O2 to water and oxygen. Catalase activity varies greatly between tissues with highest activities in the liver, kidney and erythrocyte, and lowest activity present in connective tissues. In eukaryotic cells the enzyme is concentrated in sub-cellular peroxisome organelles.

The most common definition of one catalase unit is the amount of enzyme decomposing 1.0mmole of hydrogen peroxide per minute at pH 7.0 and 25C, with initial H2O2 concentration of 10.3 mM. Catalase exhibits an unusual kinetic behavior in that it is not possible to saturate the enzyme with H2O2 substrate up to 5M catalase concentartion but there is a rapid inactivation of the enzyme at substrate concentrations above 0.1 M H2O2 . Therefore, the activity assay is typically carried out with 10-50 mM H2O2. Since H2O2 substrate must be present at substantially less than saturated concentration, the enzyme activity is dependent on precise concentration of H2O2.

The NWLSS™ Catalase activity assay method is essentially that described by Beers and Sizer, 1952 in which the decomposition of peroxide is monitored at 240 nm, with modifications to increase robustness and convenience. Our method uses a certified standard with known catalase activity units so that calibration of precise H2O2 concentration is not necessary in our assay. Similarly, experiments can be carried out at room temperature under conditions that are more accurate and convenient. Modifications are also made in our formulations to overcome problems associated with instability of diluted hydrogen peroxide and diluted enzyme standards at the room temperature so there is no need to keep them on ice and no time wasted to bring them to the assay temperature before each individual assay.

格式:96 test 酶标板或30次比色皿

样品要求:组织匀浆，细胞裂解液或其他可能含有过氧化氢酶活性的生物样品。

特异性:过氧化氢酶酶

灵敏度:检测下限为0.3 U过氧化氢酶/mL的反应混合物或6.0 U过氧化氢酶/mL的稀释样品加入反应中。

用途:过氧化氢酶活性的定量测定

储存和稳定性:在2-8℃储存时，自制造之日起6个月。

Kit Contents:

Assay Buffer.........................30 mL

Sample Dilution Buffer...............30 mL

Catalase Standard....................1 Vial

Hydrogen Peroxide (H2O2) Reagent:...1 Vial