Amylose from potato

Products may be shipped at a different temperature than the recommended long-term storage temperature. If the product quality is sensitive to short-term exposure to conditions other than the recommended long-term storage, it will be shipped on wet or dry-ice. If the product quality is NOT affected by short-term exposure to conditions other than the recommended long-term storage, it will be shipped at ambient temperature. As shipping routes are configured for minimum transit times, shipping at ambient temperature helps control shipping costs for our customers. For more information, please refer to the Storage and Transport Conditions document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/316/622/storage-transport-conditions-mk.pdf

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For more information, please refer to the Product Dating Information document: https://www.sigmaaldrich.com/deepweb/assets/sigmaaldrich/marketing/global/documents/449/386/product-dating-information-mk.pdf

This product is tested for suitability as an amylase substrate. The purity is not determined. Note that this material may contain up to 10% ethanol and 2% butanol. This information is reported on a lot to lot basis. Please see the link below to review a sample or lot specific Certificate of Analysis:
https://www.sigmaaldrich.com/product/sigma/a0512#product-documentation

The "Type" of the product has no significant meaning outside Sigma-Aldrich. The differences between products were designated by types before Sigma had established product numbers for specific products. The types were differentiated on several bases, including manufacturing method, source, and purity.

This product is soluble in 50 mM NaOH at a concentration of 1 mg/mL. The product can also be dissolved as follows (final concentration = 1 mg/ml): Dissolve 100 mg in 1 mL ethanol. Add 10 mL water and 2 mL of 10% NaOH. Heat in boiling water bath until sample dissolves, cool to ambient temperature, then dilute to 100 mL with water.

Prepare iodine solution and Solution A:  1. Iodine solution: 0.2% iodine in 2% potassium iodide.2. Solution A: To 100 mg of sample in 100 mL flask, add 1 mL ethanol. Add 10 mL water and 2 mL of 10% NaOH. Warm in boiling water bath until sample dissolves. After cooling, dilute to 100 mL with water.Transfer 2.5 mL of solution A to 250 mL flask. To this flask, add 50 mL water, then 2 drops of 6 N hydrochloric acid, followed by 2.5 mL of Iodine solution. Dilute to 250 mL with water. Read absorbance at 680 nm against a blank.The final solution to be read will be at a sample concentration of 10 μg per mL, and 1% of the iodine solution.This procedure is based on McCready, R. M., and Hassid, W. Z., The Separation and Quantitative Estimation of Amylose and Amyolpectin in Potato Starch. J. Am. Chem. Soc., Vol. 65, pp. 1154-1157 (1943).

The method of preparation is given in Street and Close, Clin. Chim. Acta, 1, 256-268 (1956). Potato starch is dissolved in boiling 2% (w/v) NaCl solution, filtered while hot, then cooled. Thymol is added, and the mixture is stirred for 48 hr. Amylopectin is decanted away in the supernatant. The precipitate is washed six times with concentrated thymol solution, four times with absolute ethanol, and dried.

Sigma-Aldrich has not determined the molecular weight of the product. One reported range is from 40,000 to 340,000 Daltons, with chains containing 250 to 2000 anhydroglucose units. Source: WHO Food Additives Series No. 5.

Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product.