Galactose is a monosaccharide that is found in dairy products, sugar beets, gums and mucilage’s. It is also synthesized in mammals, where it forms part of glycolipids and glycoproteins in several tissues. It forms the disaccharide lactose when combined with glucose. Defects in the genes encoding these proteins leads to the metabolic disorder galactosemia.

Galactose Assay Kit provides a simple, reproducible, and sensitive tool for measuring galactose concentration in plasma, serum, cell lysates, saliva, urine, and other biological liquid samples. This assay employs a coupled enzymatic reaction system that combines multiple steps. Galactose is oxidized by galactose oxidase, resulting in a colorimetric (570 nm) / fluorometric (Ex/Em = 535/590 nm) product. The absorbance / fluorescence measured is directly proportional to the concentration of galactose present in the sample.

• Microplate reader capable of measuring OD 570 nm or Ex/Em = 535/590 nm
• 96-well black plate for fluorometric assay
• Precision pipettes to deliver 2 µL to 1 mL volumes
• Tubes to prepare sample dilutions
• 5 mL tubes
• Multi-channel pipettes to deliver 20 µL to 200 µL volumes
• MilliQ water or another type of double distilled water (ddH₂O)

1. Add 50 µL of the diluted Galactose standards or samples to the 96-well microtiter plate.
2. For colorimetric reading: Add 50 µL of Working Solution to each well. Incubate the plate at room temperature for 60 minutes with mixing in the dark.
3. Measure the absorbance at 570 nm using a plate reader.
4. For fluorometric reading: Add 50 µL of Working Solution to each well. Incubate the plate at room temperature for 30 minutes with mixing in the dark.
5. Measure the fluorescence at Ex/Em = 535/590 nm using a fluorescence plate reader.