Nucleic acid extraction is a common yet critical task in the molecular biology lab. Also known as nucleic acid isolation or nucleic acid purification, removal of genetic material from the sample matrix is the first step in many genetic and genomic studies. Preparing high quality samples improves the likelihood that your experiment will work and you’ll get the results you need.
Nucleic acid extraction methods
Nucleic acid extraction and isolation starts with disrupting the cellular structures containing the genetic material—nuclei, ribosomes, bacteria, viruses; this is usually accomplished by adding a compatible detergent, mechanical disruption, and/or heat.
From there, several methods for nucleic acid purification are common. Each nucleic acid isolation method is based on a different biochemical principle. Selection of a method is based on the throughput required, equipment available in the lab, or the degree of purity required.
Organic extraction and precipitation
Nucleic acid isolation by organic extraction involves addition of phenol and guanidine isothiocyanate to separate the DNA, RNA, and proteins into different organic phases. Organic extraction is a low-cost method, and with advanced reagents such as TRIzol, is a straightforward process requiring very little equipment.
Silica-based nucleic acid isolation
Nucleic acids bind to silica (also known as glass fibers) under high-salt conditions and can be released under low-salt conditions. Silica-containing columns provide an easy way to bind, wash, and elute purified nucleic acids from multiple clarified cell lysates in parallel.
Invitrogen Purelink and GeneJET columns are designed to flow buffers through centrifugation, vacuum, or gravity. Most protocols use spin column technology to take advantage of readily available lab equipment. Spin plates provide a high-throughput format based on the same isolation principle.
Paramagnetic bead-based nucleic acid purification
In this method paramagnetic (attracted to magnet) beads are added to the sample, and nucleic acids bind to the beads. Using a strong magnet, the beads are held in place while removing unwanted material. After washing, the genetic material is eluted from the beads in water or a low-salt buffer.
Magnetic bead isolation is now one of the most popular nucleic acid extraction methods due to its scalability and automation compatibility; MagMAX Bead Kits and KingFisher Sample Purification Systems are designed to work together to efficiently purify a variety of nucleic acids.
Instruments, kits, and reagents for a variety of nucleic acid extraction and purification techniques
Our nucleic acid extraction instruments, kits and reagents are optimized to provide maximum yield, purity, and integrity from virtually any sample type. Whether you need to extract and purify RNA, viral nucleic acid, DNA fragments, plasmid DNA, or genomic DNA, Thermo Fisher Scientific has a solution.
Sensitive, scalable genomic DNA purification products help maximize your efficiency.
Select RNA extraction kits based on your application, sample, or RNA type.
Isolate, purify, and extract high-quality plasmid DNA for cloning or transfection.
Efficiently perform DNA, RNA, viral nucleic acid, and plasmid isolation with MagMAX kits and KingFisher automated nucleic acid purification systems.
Purify viral DNA and RNA with excellent reproducibility from a variety of sample types.
Purify DNA fragments with simple, rapid PCR and gel cleanup kits.
For Research Use Only. Not for use in diagnostic procedures.