Nucleic acid extraction and purification kits for genomic DNA, total RNA and plasmid DNA, with dedicated kits for blood, tissue, plant, fecal and viral RNA samples.
Last reviewed
| Kit | Starting material | Built to handle |
|---|---|---|
| Genomic DNA | Cultured cells and animal tissue | Proteinase K digestion, high molecular weight DNA |
| Blood DNA | Whole blood, buffy coat | Heme and anticoagulants that inhibit PCR |
| Plant DNA | Leaves, seeds and other plant tissue | Polysaccharides and polyphenols |
| Fecal DNA | Stool and gut content | Hard-to-lyse bacteria and humic substances |
| Total RNA | Cells and tissue | RNases, genomic DNA carry-over |
| Viral RNA | Swabs, serum, plasma, culture supernatant | Very low RNA amounts |
| Plasmid DNA | Bacterial cultures | Removing genomic DNA, RNA and protein |
Most kits bind nucleic acid to silica under high-salt conditions, wash away contaminants and elute in a low-salt buffer. They differ in how the silica is handled.
The extraction methods guide compares both with CTAB and phenol-chloroform methods, including a CTAB buffer recipe for difficult plant material.
| Check | Target | If it is off |
|---|---|---|
| A260/280 | About 1.8 for DNA, about 2.0 for RNA | Low: protein or phenol carry-over |
| A260/230 | Around 2.0 to 2.2 | Low: guanidine salts, polysaccharides or phenol |
| Gel or integrity score | Sharp high molecular weight band; intact rRNA bands | Smearing means degradation |
| Fluorometric quantification | Measures DNA or RNA specifically | Use it when absorbance overestimates |
Purified DNA and RNA usually go straight into amplification. Use the qPCR and RT-PCR reagents for quantification, and the molecular biology reagents for cloning and gel analysis. The guide to extraction by sample type covers blood, tissue, plant, stool, viral samples and plasmid minipreps one by one.
A blood DNA kit, which removes heme and other PCR inhibitors. Collect blood in EDTA tubes: heparin co-purifies with DNA and inhibits PCR. For RNA from blood, use a kit designed for blood RNA and stabilise the sample at collection.
Yes, either with a co-extraction kit or by splitting the lysate between a DNA and an RNA protocol. Tell us the sample type and amount and we suggest the simplest option.
Usually because of carry-over from the binding buffer's guanidine salts, or polysaccharides and phenolics from plant material. An extra wash, a longer spin to dry the membrane before elution, or a kit designed for the sample type usually fixes it.
Store DNA in a slightly alkaline buffer such as 10 mM Tris pH 8.0 or TE, at 4 °C for days and -20 °C or colder for long periods. Store RNA at -80 °C in aliquots, and avoid repeated freeze-thaw for both.
A small-scale plasmid purification from 1–5 mL of overnight bacterial culture, using alkaline lysis followed by a silica column. A high-copy plasmid typically yields enough DNA for sequencing, restriction digests and transfection.
DNA and RNA extraction
Every extraction does the same four things: lyse, separate, wash, elute. The chemistry you use for each step decides yield, purity and how many samples you can run a day.
4 minute read
DNA and RNA extraction
Blood brings heme, plants bring polysaccharides, stool brings humic acids and tough bacteria, viral samples bring almost no RNA. Here is what each sample needs from an extraction kit.
4 minute read
DNA and RNA extraction
A poor A260/230 usually means salt or phenol carry-over rather than bad RNA. Low yield usually starts at lysis. Here is how to read the numbers and what to change.
3 minute read
Send the details on the right with your list. Orders often combine ranges, so add anything else you need and we quote it together.
Your enquiry
What to tell us
Product names or catalogue numbers, quantities and the delivery country. We'll confirm availability, lead time and the documents that ship with the order.