Description
Starch Assay Kit (Colorimetric or Fluorometric) (BA0068) (BA0068)
The Starch Assay Kit (SKU: BA0068) offers a simple, direct and automation-ready method for measuring starch concentration. Starch is a polysaccharide carbohydrate consisting of many glucose units joined by glycosidic bonds and is present in all plant seeds and tubers as amylose and amylopectin. It is the most consumed polysaccharide in the human diet: some starches are digested quickly and cause a rapid rise in blood sugar, while resistant starch is not digested in the small intestine and causes little or no rise. This assay uses a single working reagent that combines the enzymatic breakdown of starch and the detection of glucose in one step. The colour intensity at 570 nm, or fluorescence intensity at excitation/emission 530/585 nm, is directly proportional to the starch concentration. The convenient assay is carried out at room temperature and takes only 30 minutes.
| Product Name: | Starch Assay Kit (Colorimetric or Fluorometric) (BA0068) |
| SKU: | BA0068 |
| Detection Method: | Colorimetric or Fluorometric |
| Detection Range: | Colorimetric 2 to 200 ug/mL; fluorometric 0.2 to 20 ug/mL starch |
| Sample Type: | Plant seeds, tubers and other starch-containing samples |
| Species Reactivity: | All |
| Assay Time: | 30 minutes |
| Kit Size: | 100 Assays |
| Equipment Required: | Microplate reader |
| Storage: | -20C |
| Shelf Life: | 6 months after receipt |
| Shipping: | Gel Pack |
Quantitative colorimetric or fluorometric determination of starch. A single working reagent combines the enzymatic breakdown of starch and detection of the released glucose, read at 570 nm or fluorometrically at excitation/emission 530/585 nm.
- Uses as little as 10 uL sample
- Colorimetric linear detection range 2 to 200 ug/mL starch
- Fluorometric linear detection range 0.2 to 20 ug/mL starch
- Convenient room-temperature assay completed in 30 minutes
- Starch determination in plant and other biological samples in research and drug discovery
- Distinguishing soluble starch from resistant starch fractions
Note: The below protocol is a sample protocol. Protocols are specific to each batch/lot. For the correct instructions please follow the protocol included in your kit.
| Step | Procedure |
| 1 | Reagent preparation. Reconstitute Enzyme A by adding 120 uL Assay Buffer and pipetting until fully dissolved; store reconstituted Enzyme A at -20C and use within 1 month. |
| 2 | Sample preparation. For soluble starch, grind 5-10 mg sample, wash off free glucose and small oligosaccharides with 1 mL 90% ethanol at 60C for 5 minutes with occasional vortexing, centrifuge at 10,000 g for 2 minutes and repeat the wash twice. Extract soluble starch from the pellet with 1 mL water in a boiling water bath for 5 minutes and spin; the supernatant is soluble starch. For resistant starch, extract the insoluble pellet with 0.2 mL DMSO in a boiling water bath for 5 minutes and dilute 1:100 in water before assay. |
| 3 | Standards and samples. Equilibrate components to room temperature. Dilute standard by mixing 5 uL Standard with 1.245 mL distilled water (200 ug/mL), prepare the dilution series shown in the table and transfer 10 uL standards and samples into separate wells of a clear plate; for samples containing glucose, transfer an additional 10 uL for a Sample Blank. |
| 4 | Working reagent. For each reaction well mix 90 uL Assay Buffer, 1 uL Enzyme A, 1 uL Enzyme B and 1 uL Dye Reagent (omit Enzyme A for Sample Blanks). Transfer 90 uL working reagent into each well and tap to mix. |
| 5 | Incubate 30 minutes at room temperature and read OD at 570 nm (550-585 nm). For fluorometric assays use 0, 5, 10, 15 and 20 ug/mL standards in a black plate and read fluorescence at excitation/emission 530/585 nm. |
Subtract the blank reading (OD at 570 nm or fluorescence) from the standard readings and plot the change in OD or fluorescence against standard concentrations to determine the slope. Starch = (Rsample - Rblank) / slope ug/mL, where Rsample and Rblank are the values of the sample and blank.
| Component | Quantity | Storage |
| Assay Buffer | 12 mL | -20C |
| Enzyme A (dried) | 1 vial | -20C |
| Enzyme B | 120 uL | -20C |
| Dye Reagent | 120 uL | -20C |
| Standard (50 mg/mL) | 50 uL | -20C |
