Potassium sodium tartrate tetrahydrate Product Number S 2377 Store at Room Temperature Product Description Molecular Formula: C4H4KNaO6 • 4H2O Molecular Weight: 282.2 CAS Number: 6381-59-5 Melting Point: 70-80 °C Synonym: sodium potassium tartrate tetrahydrate, Rochelle salt, Seignette salt 1 Potassium sodium tartrate is a reagent that is used in large scale applications such as the manufacture of mirrors and the control of radio frequencies. Historically, it has been a component of Fehling's solution for the detection of aldehydes. Potassium sodium tartrate may also be prepared in the form of piezoelectric crystals, or crystals which undergo dimensional deformation under the stress of externally applied electric fields, leading to changes in the crystalline structure. Such crystals find application in various electronic applicances. 1 Potassium sodium tartrate has been commonly used in protein crystallization. 2,3,4,5,6 A block silver impregnation technique for central nervous systems samples that utilizes potassium sodium tartrate has been described. 7 An electron-cytochemical protocol for the localization of phospho(enol)pyruvate carboxylase in fungal cells has been published. 8 A colorimetric assay for reducing sugars that uses potassium sodium tartrate in conjunction with tetrazolium blue in basic solutions has been reported. 9 Precautions and Disclaimer For Laboratory Use Only. Not for drug, household or other uses. Preparation Instructions This product is soluble in water (100 mg/ml), yielding a clear, colorless solution. The pH of aqueous solutions of this product is slightly alkaline, in the pH range 7-8. This product is virtually insoluble in alcohol. 1 References 1. The Merck Index, 12th ed., Entry# 7840. 2. Johansson, P., et al., Crystallization and preliminary X-ray analysis of a xyloglucan endotransglycosylase from Populus tremula x tremuloides. Acta Crystallogr. D Biol. Crystallogr., 59(Pt 3), 535-537 (2003). 3. McPherson, A., A comparison of salts for the crystallization of macromolecules. Protein Sci., 10(2), 418-422 (2001). 4. Nichols, C. E., et al., Identification of many crystal forms of Aspergillus nidulans dehydroquinate synthase. Acta Crystallogr. D Biol. Crystallogr., 57(Pt 2), 306-309 (2001). 5. Sinclair, J. C., et al., Purification, characterization, and crystallization of an N-hydroxyarylamine Oacetyltransferase from Salmonella typhimurium. Protein Expr. Purif., 12(3), 371-380 (1998). 6. Almo, S. C., et al., Purification, characterization and crystallization of Acanthamoeba profilin expressed in Escherichia coli. J. Mol. Biol., 236(3), 950-952 (1994). 7. Abadia-Fenoll, F., et al., A modification of the chronic tartrate silver impregnation technique for block impregnation of the central nervous system and paraffin wax embedding. J. Microsc., 137(Pt 3), 225-232 (1985).