• Ampicillin trihydrate, USP packaged and labeled.

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SKU: A009

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Ampicillin trihydrate, USP is a member of the extended spectrum β-lactam family and similar in structure to penicillin. Ampicillin resistance is frequently due to secretion of plasmid encoded ESBLs.

TOKU-E offers five forms of ampicillin:

In aqueous solution, ampicillin sodium is freely soluble (50 mg/mL). Ampicillin trihydrate is slightly soluble in water (10 mg/mL) and freely soluble in 1 N HCl (50 mg/mL). Ampicillin anhydrous is sparingly soluble in water and freely soluble in 1 N NH4OH (50 mg/mL). Ampicillin sodium is commonly used to select for successfully transformed bacteria. Ampicillin anhydrous (powder) is the most stable and pure form of ampicillin TOKU-E offers.

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    Mechanism of Action

    Like all β-lactams, ampicillin interferes with PBP (penicillin binding protein) activity otherwise involved in the final phase of peptidoglycan synthesis. PBP’s are enzymes which catalyze a pentaglycine crosslink between alanine and lysine residues. Without a pentaglycine crosslink, the integrity of the cell wall is severely compromised ultimately leading to cell lysis.

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    Ampicillin, USP targets non-ESBL (Extended Spectrum β-lactamase) bacteria including Staphylococcus and Streptococcus species and medically important enteric pathogens such as Shigella and Salmonella. Interestingly, ampicillin has been found to be effective against certain β-lactam sensitive VRE or vancomycin resistant Enterococcus; a glycopeptide antibiotic resistant "superbug." Resistance to ampicillin is routinely utilized as a selectable marker to confirm successful cell transformation.


    Eukaryotic Cell Culture Applications

    Ampicillin is routinely used to select for cells containing the pcDNA3.1 and pEAK10 resistance plasmids in cell line A904L at an effective concentration of 50 µg/mL. For additional information on your cell culture needs, please visit our cell-culture database.

    Microbiology Applications

    Ampicillin trihydrate is often used to select for cells that have been transformed with a plasmid containing the ampR gene which confers resistance to ampicillin. Ampicillin sodium is typically used at a concentration of 50-100 µg/mL and 35-50 µg/mL.

    Media Supplements

    Ampicillin trihydrate can be used as a selective agent in several types of isolation media:

    Aeromonas Medium Base - Ampicililn Selective Supplement





    White crystalline powder



    Water Content (Karl Fischer)



    3.5 - 6.0


    (On Dried Basis): 900-1050µg/mg


    Dimethylaniline: Meets the specifications



    Guzmán, Flavio, MD. "Beta Lactams Antibiotics (penicillins and Cephalosporins) Mechanism of Action.” Medical Pharmacology. Pharmacology Corner, 29 Nov. 2008. Web. 21 Aug. 2012.

    Pitout JD, Sanders CC, Sanders WE Jr. Antimicrobial resistance with focus on beta-lactam resistance in gram-negative bacilli. Am J Med 1997; 103:51.

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