等级
analytical standard
质量水平
分子量
Mn ~60,000
Mw 750,000
浓度
50 % (w/v) in H2O
技术
gel permeation chromatography (GPC): suitable
格式
single component solution
InChI
1S/C2H5N/c1-2-3-1/h3H,1-2H2
InChI key
NOWKCMXCCJGMRR-UHFFFAOYSA-N
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应用
警示用语:
Warning
危险分类
Acute Tox. 4 Oral - Aquatic Chronic 2 - Eye Irrit. 2 - Skin Sens. 1
WGK
WGK 2
闪点(°F)
Not applicable
闪点(°C)
Not applicable
个人防护装备
Eyeshields, Faceshields, Gloves, type ABEK (EN14387) respirator filter
Which document(s) contains shelf-life or expiration date information for a given product?
If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.
How do I get lot-specific information or a Certificate of Analysis?
The lot specific COA document can be found by entering the lot number above under the "Documents" section.
What is the molar concentration of Product P3143, Poly(ethyleneimine) solution?
This product is nominally a 50% w/v solution of PEI in water, meaning 50 grams of poly(ethyleneimine) per 100 mL of solution. Concentrations of polymer solutions (such as PEI) are commonly reported either as a percentage or mg/mL, not in terms of molarity.
The product description of Product P3143, Poly(ethyleneimine) solution, on sigmaaldrich.com appears to give two molecular weight values, Mn and Mw. What do those abbreviations stand for, and why are the two values so different?
Mn is the number average molecular weight. This corresponds to the "true average" or mean; that is, the sum of the molecular weights divided by the number of molecules. Mw is the weight average molecular weight. This corresponds to the median value; that is, there are as many molecules smaller than the weight average molecular weight as there are larger than the weight average molecular weight. The fact that the two molecular weight values are so different means that there is a large, non-symmetrical distribution of molecular weights; the largest molecules probably have a molecular weight of several million.
What is the purity of Product P3143, Poly(ethyleneimine) solution?
This product is a polymer with a large molecular weight distribution. It is not amenable to being analyzed by typical chromatographic assays such as HPLC or TLC. Therefore, we do not report an overall purity value for this product.
Do you have any references that describe using Product P3143, Poly(ethyleneimine) solution, in enzyme isolation or for transfections?
For enzyme isolation, see:J.J. Jendrisak and R.R. Burgess, Biochem., 14(21), 4639-4645 (1975), "A new method for the large-scale purification of wheat germ DNA-dependent RNA polymerase II".This paper describes preparing a 10% stock solution, which was adjusted to pH 7.9 by adding hydrochloric acid.PEI has also been used for the precipitation of nucleic acids in the purification process of aminoacyl-tRNA synthetases:von der Haar, F., "Purification of Aminoacyl-tRNA Synthetases", Methods in Enzymology, 59, 257-267 (1979).For transfections, see the following references:Boussif, O. et al., "A versatile vector for gene and oligonucleotide transfer into cells in culture and in vivo: Polyethylenimine." Proc. Natl. Acad. Sci. USA, 92(16), 7297-7301 (1995).Thomas, M. and Klibanov, A.M., "Conjugation to gold nanoparticles enhances polyethylenimine's transfer of plasmid DNA into mammalian cells." Proc. Natl. Acad. Sci. USA, 100(16), 9138-9143 (2003).
How do I find price and availability?
There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote. USA customers: 1-800-325-3010 or view local office numbers.
What is the Department of Transportation shipping information for this product?
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.
My question is not addressed here, how can I contact Technical Service for assistance?
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