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NP-40 is an ethoxylated nonylphenol for non-ionic surfactants and can act as emulsifier and demulsifier agent. NP-40 is often used to break open all membranes within a cell, including the nuclear membrane [citation needed]. To break only the cytoplasmic membrane, other detergents such as digitonin can be used.
Nonidet P-40 is a nonionic, non-denaturing detergent.Its official IUPAC name is octylphenoxypolyethoxyethanol.. Nonidet P-40 is sometimes abbreviated as NP-40, but should not be confused with a different detergent by the same name NP-40, nonylphenoxypolyethoxyethanol of the Tergitol NP series of Dow Chemicals.
IGEPAL CA-630 has HLB of 13.4, similar to that of Triton X-100 (13.4) and thus belongs to the detergent range (HLB 13-15); this is significantly less than 17.8 of tergitol NP-40 or 16.7 of Polysorbate 20 (also known as Tween 20), which both belong in the solubilizer range (15-18) of HLB. [2] Ca-630 is completely miscible with water.
To make NPEs, manufacturers treat NP with ethylene oxide under basic conditions. [12] Since its discovery in 1940, nonylphenol production has increased exponentially, and between 100 and 500 million pounds of nonylphenol are produced globally every year, [ 12 ] [ 16 ] meeting the definition of High Production Volume Chemicals .
The gram-atom is a former term for a mole of atoms, and gram-molecule for a mole of molecules. [ 7 ] Molecular weight (M.W.) (for molecular compounds) and formula weight (F.W.) (for non-molecular compounds), are older terms for what is now more correctly called the relative molar mass ( M r ). [ 8 ]
Parts-per notation is often used describing dilute solutions in chemistry, for instance, the relative abundance of dissolved minerals or pollutants in water.The quantity "1 ppm" can be used for a mass fraction if a water-borne pollutant is present at one-millionth of a gram per gram of sample solution.
The equivalent weight of an element is the mass which combines with or displaces 1.008 gram of hydrogen or 8.0 grams of oxygen or 35.5 grams of chlorine. The equivalent weight of an element is the mass of a mole of the element divided by the element's valence. That is, in grams, the atomic weight of the element divided by the usual valence. [2]
XLT Agar (Xylose Lysine Tergitol-4) is a selective culture medium for the isolation and identification of salmonellae from food and environmental samples. It is similar to XLD agar; however, the agar is supplemented with the surfactant, Tergitol 4, which causes inhibition of Proteus spp. and other non-Salmonellae. [1]