Services | DNA Sequencing | Plasmids


Bacterial plasmids are an essential tool in modern molecular biology research and there are many different plasmids used for various purposes, including basic cloning, expression in a range of cell types and mutagenesis of inserts. Ensuring the fidelity of these inserts is critical for all subsequent studies. By undertaking DNA sequencing on your plasmids, we can rapidly provide the key information that enables you to move forward with your research.

We consider plasmids of up to about 20kb in length to be ‘standard’ and we recommend our standard sequencing reaction protocol for such plasmids. If your plasmid is larger than this, you should select our "Large Template" option, which is specifically designed to give improved results with large plasmids.

Please review the information below prior to submission so that you get the best out of the sequencing process.


Materials Requested Per Reaction (August 2017: Please note changed amounts!)

Plasmid: 500-600 ng plasmid in 20 ul (approximately 25-30ng/ul concentration)

  • NOTE: increased concentration, but reduced total volume per reaction (i.e. one template sequenced with one primer).
  • We can "get away" with a lower total volume per reaction (do not give us less than 5ul per reaction if requiring more than one reaction or 10ul if you need only a single reaction - evaporation will be an issue otherwise and we may not have enough material to work with). The above amount is actually more than we need for a single reaction, but we specify that amount to allow for repeats.
  • Also, we can "wave a magic wand" and often get results with DNA concentrations lower than 25-30ng/ul. However, the reaction will be sub-optimal and results may be impaired. If you intend to send us plasmid DNA that is of lower concentration than requested, please let us know this on your submission form.
  • Please ensure your template is diluted in water or a buffer that does not contain EDTA (e.g. Tris-EDTA buffer), which can inhibit the sequencing reaction. 
  • Not sure how much template to provide for your reaction? If you would like to save time, we are happy to take care of this step for you. Just click ‘Quant-it’ on the sample submission page and send us your undiluted plasmid prep.

Primer*: 12 pmole

  • When sending primer separately, please send a minimum of 10µl of 3.2 uM primer stock to avoid issues associated with evaporation. We use about 3-4 pmole (1ul) of primer in a standard reaction.

*Note: This applies if you are submitting the primer and template mixed together in a single tube and send 20ul with 500-600ng of template and 12 pmole primer.



Special Considerations

DNA Quality

High quality plasmid DNA is essential to achieve the best results. We would recommend a good quality mini-prep, midi-prep or maxi-prep plasmid DNA kit. Alternatively, we are happy to process your preps for you to yield DNA of appropriate quality (conditions apply in terms of copy number and plasmid size). Please look at the appropriate service page on our website for mini-, midi- or maxi-preps. We cannot stress too highly the need for plasmid DNA of the highest quality. Even when using commercial plasmid isolation kits and following the kit instructions carefully (including performing all the "optional" steps), sometimes it will be impossible to isolate DNA of the required quality when using mini-preps. This is often the case with low copy number plasmids. In such cases, we advise that midi- or maxi-preps are undertaken.

Read Length

There are many factors that can affect the read length obtained. We will endeavour to provide customers with the longest read possible depending on service requested. Our new ABI 3730 sequencers use the latest technology and provide really excellent results with high quality templates and primers.

With a template of appropriate quality, customers can expect read lengths of over 1000 bases of sequence from a single primer when sequencing standard templates (<20kb). For other types of template (especially for large templates), read lengths can decrease due to issues of template quality and quantity. If you are having problems achieving good read lengths, please take a look at our resources section for some help and advice. If you still need more help, please feel free to contact us.



Services Requested Pricing (per Reaction)
Sequencing  £5.00
Sequencing + Quant-It* £6.00
Sequencing + Augmented Protocol^ £5.50
Sequencing + Quant-It* + Augmented Protocol^ £6.50


  • *Quant-It: We are happy to quantitate the concentration of your template for only £1. Please note that when sending samples for quantifying, we require a minimum volume of 10ul of material. This is because we have to use some for the quantification and if too little is sent, there will not be enough left after quantification.
  • ^Augmented Protocol: If your template has known secondary structure or a high GC content, you can select our augmented protocol - £0.50 will be applied per reaction to facilitate this.

Do you routinely sequence a large number of plasmids?

Why not contact our staff to learn about savings options?

Our pre-payment option will help you save more per reaction!


  • Standard primers offered by MRC PPU DNA Sequencing & Services are free!
  • Custom primer synthesis prices will reflect the size of the primer – the cost to the customer is £0.50 per base

Learn more about all our pricing and turnaround.

Please note that prices are exclusive of VAT, which customers outside The University of Dundee will be charged at the appropriate rate (currently 20%) on all products and that all sales are subject to MRC PPU DNA Sequencing and Services' Terms and Conditions.

Turnaround Time

Results are routinely supplied to customers within 24 hours upon receipt of primer and template.  


Shipping Details

  • Labels
    • Please ensure that samples are clearly labeled so that we can identify them.
  • Packing Materials
    • Eppendorf Tubes
      • Please also ensure that your samples are well protected and packaged to meet Post-Office or courier regulations
        • A "Jiffy" style padded envelope for DNA samples in plastic tubes works well
        • Please don't use a regular envelope as these are often put through the automatic sorting machine by the Royal Mail and crushed/torn. When we receive the envelope, there is inevitably nothing inside....


Postage Costs

  • Customers are responsible for paying all postage / carriage charges for samples sent to us
    • For most samples, normal first class post should be sufficient
      • As this does not always arrive as "next day post", we recommend that customers who have deadlines to meet send their samples by a guaranteed next day delivery service
  • Insufficient postage provided on a package will cause a delay in use receiving the package
    • If we are charged upon receipt for outstanding postage/fines, we will need to pass this cost onto you


Postal Address:

DNA Sequencing and Services
Medical Sciences Institute
School of Life Sciences
University of Dundee


(01382) 388019


(01382) 388729


Do you need any help? Please get in touch and we’ll be happy to lend a hand.