Cell-based Assays

Urea is the end product of nitrogenous compound degradation in living organisms, undergoing conversion to ammonia under the catalysis of urease. Blood urea nitrogen (BUN) is one of the principal indicators of renal function. In a sample, urea nitrogen reacts in a solution containing ferric chloride and phosphate, along with diacetyl monoxime and thiourea, upon heating to produce a red diazine compound. The intensity of the color of this compound is directly proportional to the concentration of urea nitrogen present. The determination of urea nitrogen levels is accomplished using the diacetyl monoxime method, which relies on colorimetric analysis of the reaction mixture to quantify urea nitrogen content in serum or urine specimens.

Polyamine oxidase (PAO) is a key enzyme that catalyzes the oxidation of polyamines in organism. In addition, PAO can regulate the level of polyamines and the concentration of products in organism, and participate in the response to stress and the growth and development process of each plant. CheKine™ Micro Polyamine Oxidase (PAO) Activity Assay Kit can detect biological samples such as Animal and Plant Tissues, Serum or Plasma. In this kit, PAO catalyzed the oxidation of polyamines to produce hydrogen peroxide, which reacts with the substrate in the presence of peroxidase, and the product has a characteristic absorption peak at 500 nm. The activity of PAO is reflected by measuring the rate of increase in absorbance value.

Lipoprotein lipase (LPL) is an enzyme synthesized by adipocytes, cardiomyocytes, skeletal muscle cells, mammary cells, macrophages and other parenchymal cells. LPL catalyzes the hydrolysis of triglyceride to fatty acids and monophosphate for tissue oxidation for energy supply and storage. Hydrolysis of 4-nitrobenzene palmitate by LPL yields 4-nitrophenol with a characteristic absorption peak at 400 nm.

Mammalian CarE also known as aliphatic esterase (aliesterase) is widely distributed in tissue and organism, belonging to the serine hydrolase family. CarE catalyze hydrolysis of endogenous and exogenous substances containing ester bonds, amide bonds, and thioester bonds, but can’t catalyze hydrolysis of acetylcholine and its analogues. CarE take part in lipid transport and metabolism, and related with detoxification and metabolism of many drugs, environmental poisons and carcinogens. Organophosphorus pesticides can bind to CarE and inhibit CarE activity. CarE can catalyze acetic acid-1-naphthalene ester to produce naphthalene ester, solid blue color development. Determination of 450 nm light absorption increase rate could calculate CarE activity.

Pepsin is secreted by the main cells of the gastric mucosa and breaks down proteins in food into small peptides. Generally used for the identification of neuropathic hypoacidosis, chronic gastritis, chronic gastric dilatation, chronic duodenitis and other symptoms will also cause the decrease of pepsin secretion. CheKineTM Micro Pepsase Activity Assay Kit can be used to detect biological samples such as animal tissues. In the kit, pepsase can catalyze the hydrolysis of hemoglobin, and the hydrolysate appears blue after reacting with Folin reagent, and the color of pepsin is proportional to the activity of pepsin in a certain range.

Betaine is a kind of quaternary ammonium type water-soluble alkaloid widely distributed in animals, plants and microorganisms. It is the oxidation product of choline in organism. It can enhance immunity, reduce blood lipid, resist oxidation and anti-tumor. It can also be used as a methyl donor to promote protein and fat metabolism, increase appetite, relieve stress, regulate osmotic pressure, stabilize vitamins and other biological functions It is widely used in chemical industry, medicine, food additive and other fields. CheKine TM Micro Betaine Content Assay Kit can be used to detect biological samples such as animal and plant tissues. In the kit, under strong acid conditions, betaine reacts with Raynaud salt to produce precipitation. The precipitation is dissolved in acetone to form a red solution. There is a characteristic absorption peak at 525 nm. The absorption value at 525 nm is determined to obtain the content of betaine in the sample.

Vitamin E (VE) is a fat-soluble vitamin whose hydrolysis product is tocopherol, one of the primary antioxidants in biological systems. It serves to prevent unsaturated fatty acids from oxidative damage, thereby maintaining the integrity and normal functionality of cell membranes composed of such acids. It possesses the ability to retard aging processes and is effective in preventing hemolytic anemia. Vitamin E holds considerable application value in the pharmaceutical, cosmetic, health supplement, and food industries.VE reduces Fe3+ions to Fe2+, whichsubsequently forms a colored complex with 1,10-phenanthroline. Thiscomplex exhibits a characteristic absorption peak at a wavelength of 530 nm.

Alcohol is the general name of alcoholic (ethanol) beverages, ethanol is the main component of alcohol, is one of the important indicators to measure the quality of wine. Ethanol can be used to manufacture acetic acid, beverages, flavors, dyes, fuels, etc. In medical treatment, ethanol with a volume fraction of 70% to 75% is commonly used as a disinfectant. Ethanol is widely used in chemical industry, medical care, food industry, agricultural production and other fields. CheKine™ Micro Ethanol Content Detection Kit can detect biological samples such as Animal and Plant Tissues, Cells, Bacteria, Serum or Plasma. In this kit, ethanol is oxidized and dehydrogenated to produce acetaldehyde under the catalysis of ethanol dehydrogenase, while NAD is reduced to NADH, which makes WST-8 orange color under the action of 1-mPMS. Ethanol content can be measured by the change of absorbance value at 450 nm.

Acetaldehyde dehydrogenase (EC 1.2.1.10, ALDH) is a kind of aldehyde dehydrogenase, which is widely present in various animals, plants and microorganisms. The main effect is the oxidation of acetaldehyde to acetic acid, which plays a major role in alcohol metabolism. In humans and many animals, mitochondrial aldehyde dehydrogenase (MDA) can convert alcohols that are harmful to organisms, so it has attracted great attention in the research of cellular detoxification. At the same time, aldehyde dehydrogenase has been widely used in molecular biology and the detection of related diseases. In the presence of coenzymeⅠ, acetaldehyde dehydrogenase catalyzes the conversion of acetaldehyde and NAD+ to acetate and NADH, and the absorbance value at 340 nm increases. The activity of acetaldehyde dehydrogenase can be calculated by measuring the absorbance value at 340 nm.