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  • LITMUS 28i Vector


    LITMUS 28i is a multi-purpose cloning/in vitro transcription phagemid vector. The molecule is a small, double-stranded circle 2,823 base pairs in length (molecular weight =1.8 x 106 daltons).

    DNASU is a central repository for plasmid clones and collections that may also be helpful.


    • Extensive set of restriction sites in polylinker, many with unique 4-base overhangs 
    • Blue/white selection
    • Opposing T7promoters for making RNA transcripts in either direction or double-stranded RNA using the HiScribe™ T7 In Vitro Transcription Kit (NEB #E2030)

    Product Source

    LITMUS 28i is isolated from E. coli ER2272 by a standard plasmid purification procedure.


    Advantages and Features


    • Small (< 3 kb), high copy number.
    • Ampicillin resistance.
    • Single-stranded (M13) DNA replication origin.
    • Compatible with pUC/M13 sequencing primers as well as LITMUS sequencing primers.

    Properties and Usage

    Affinity Tag


    Storage Temperature



    1. Appropriate strains of E. coli containing the LITMUS 28i plasmid form blue colonies on X-gal plates; when a fragment is inserted in the polylinker, the colonies are white. Blue/white selection is best achieved by plating on a rich media (e.g. LB) supplemented with X-gal (40 µg/ml) and IPTG (0.1 mM).

    Supporting Documents

    Material Safety Datasheets

    The following is a list of Material Safety Data Sheets (MSDS) that apply to this product to help you use it safely. The following file naming structure is used to name these document files: [Product Name] MSDS. For international versions please contact us at info@neb.com.


    The Product Summary Sheet, or Data Card, includes details for how to use the product, as well as details of its formulation and quality controls. The following file naming structure is used to name the majority of these document files: [Catalog Number]Datasheet-Lot[Lot Number]. For those product lots not listed below, please contact NEB at info@neb.com or fill out the Technical Support Form for appropriate document.
    1. How homogeneous is the DNA/ how much is supercoiled?
    2. Are the plasmids cesium purified?
    3. What primers should I use to sequence an insert (pUC19, pNEB193, LITMUS)?

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