Application 

This kit can be used to measure the D-xylose content in animal serum (plasma), urine and other samples.

Detection significance
D-Xylose is a sugar first isolated from wood, and named for it. D-Xylose is classified as a monosaccharide of the aldopentose type, which means that it contains five carbon atoms and includes an aldehyde functional group. It is derived from hemicellulose, one of the main constituents of biomass. Like most sugars, it can adopt several structures depending on conditions. With its free aldehyde group, it is a reducing sugar. 
D-xylose can be eliminated by kidney. Its incomplete absorption allows for its possible use as a absorption test. A number of studies have utilized D-xylose absorption as an investigative tool to study small intestinal function and renal function in a variety of clinical settings

Detection principle
D-xylose can produce furfural by dehydration in strong acid solution. The generated furfural reacts with Phloroglucinol to form pink compounds. The content of D-xylose can be calculated by colorimetric assay at 554 nm.

Experimental instrument

Micropipettor, Vortex mixer, Centrifuge, Spectrophotometer (554 nm), Water bath.

Operation steps

It is recommended to take 2~3 samples which expected large difference to do pre-experiment before formal experiment.

Serum, plasma or urine: Collect the serum, plasma or urine samples by conventional methods. Detect the sample directly.

Operation steps

(1)  Blank tube: add a* mL of double-distilled water into a 10 mL glass tube.

Control tube: add a* mL of sample which not treated with D-xylose into a 10 mL glass tube.

Standard tube: add a* mL of 1.33 mmol/L standard solution into a 10 mL glass tube.

Sample tube: add a* mL of sample which treated with D-xylose into a 10 mL glass tube.

 Note: a* refers to the volume of double-distilled water, 1.33 mol/L standard solution or sample.

Reference sample volume: Serum is 30 μL, urine is 50 μL.   

(2) Add 3 mL of Reagent 1 into each tube.

(3) Incubate the tubes at 100℃ (boiling water bath) for 4 min exactly. Take the tubes out and cool with running water immediately.

(4) Set to zero with double-distilled water and measure the OD values of each tube at 554 nm with 1 cm diameter cuvette.

Notes: Some of the reagents are irritating and should be operated in the ventilation cabinet.

Note: It can be refer to the following operating table.

Technical parameters

1. The sensitivity of the kit is 0.007 mmol/L.

2. The intra-assay CV is 2.2 % and the inter-assay CV is 4.5 %.

3. The recovery of the kit is 103 %.

4. The linear range of the kit is 0.007-4 mmol/L.

Notes

1. This kit is for research use only.

2. Instructions should be followed strictly, changes of operation may result in unreliable results.

3. The validity of kit is 6 months.

4. Do not use components from different batches of kit.