Solid Phase Reversible Immobilization (SPRI) beads are a simple and effective reagent for DNA purification, but not for short oligo purification. The beads are paramagnetic particles coated with carboxyl groups that can reversibly bind to nucleic acid. However, SPRI beads can only purify DNA/RNA fragments that are 100 base pairs or longer. DNA/RNA fragments shorter than 100 base pairs are not effectively recovered.
Detail
Magnetic Beads (Short Oligo Purification)
Solid Phase Reversible Immobilization (SPRI) beads are a simple and effective reagent for DNA purification, but not for short oligo purification. The beads are paramagnetic particles coated with carboxyl groups that can reversibly bind to nucleic acid. However, SPRI beads can only purify DNA/RNA fragments that are 100 base pairs or longer. DNA/RNA fragments shorter than 100 base pairs are not effectively recovered.
Oligo purification can also be performed using spin column-based technology. The oligo size limitation for recovery is around 20 nt, as oligos under 20 nt have a very low recovery rate.
We have developed Magnetic Beads (Short Oligo Purification) Kit for short oligo purification. Our proprietary bead technology enables the recovery of oligos as short as 6 nt. 80% of the 6 nt oligos and 90% of the > 8 nt oligos can be recovered. The reagent also effectively removes impurities and unwanted components such as salts, proteins, dNTPs, detergents, and other contaminants. The magnetic bead reagents are RNase free, and can be used for both DNA and RNA applications.
Recovery rates of of short oligos. Oligos with different sizes were used as input. BioDynami Short Oligo Quantification Kit (Cat. # 40046) was used to quantify the recovery rates with modifications.
Features
Effective purification of short oligos
6 nt oligos: 80% recovery rate
>8 nt oligos: >90% recovery rate
Removal of impurities and unwanted reaction components
Gel images of different ranges of library size selection. Sheared human genomic DNA was used as input.
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Library size selection is an enrichment of a specific range of library sizes for NGS library preparations. The NGS library preparation is related to the quality of the sequencing data. Precise NGS library size selection can increase sequencing efficiency, improve data quality, and reduce costs.
There are two types of sequencing technologies: short-read sequencing and long-read sequencing. Short-read sequencing uses DNA libraries that contain small insert DNA fragments of similar sizes, usually several hundred base pairs. The sequencing efficiency can be improved if the DNA size selection is in the right range. Cat.# 20104S and 20104L are the best kits for NGS library size selection of illumina paired-end 100 (PE100) sequencing with 100-200 bp library inserts; Cat.# 20105S and 20105L are the best kits for NGS library size selection of illumina paired-end 150 (PE150) sequencing with 150-300 bp library inserts; and Cat.# 20106S and 20106L are the best kits for NGS library size selection of illumina paired-end 300 (PE300) sequencing with 300-600 bp library inserts.
Long-read sequencing uses a large DNA fragment as input and makes very long reads. Usually, library size selection is preferred to remove smaller fragments. Cat.# 20110S and 20110L are the best kits for long-read sequencing size selection with DNA sizes >5 kb, and Cat.# 20111S and 20111L are the best kits for long-read sequencing size selection with DNA sizes >10 kb.
The magnetic beads, or SPRI (Solid Phase Reversible Immobilization) beads, is well used for the purification of DNA due to their reversible DNA binding. The NGS library can be size-selected by the magnetic beads or SPRI beads. The properties of the magnetic beads can be changed for a specific range of DNA binding. The contaminants and other unwanted components in the libraries can also be removed during size selection.
Specific ranges of NGS libraries can be selected using magnetic beads with different buffer compositions. The first DNA-beads binding step, also called the right-side clean-up, removes large NGS library fragments. The large NGS library fragments that bind to the beads are discarded with the beads pellet. The desired NGS library fragments in the supernatant are transferred to a new well, and new beads are added to the supernatant for the second beads-DNA binding, also called the left-side clean-up. After the rinsing step, the NGS library fragments with the dual selection are eluted in water or an appropriate buffer. The magnetic beads method has great advantages over time-consuming column purification and tedious gel-based purification.
NGS library size selection with dual clean-ups.
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Library size selection for long-read sequencing only requires a single clean-up. In this case, only the large library fragments are bound to the beads, while other small library fragments are discarded with the supernatant. The selected larger library fragments are eluted in water or an appropriate buffer after the rinsing step.
NGS library size selection with single clean-up for >5 kb and >10 kb libraries.
Principle: Beef extract powder and casein hydrolyzate provide nitrogen, vitamins and amino acids; soluble starch absorption of toxic metabolites.
Formulation(per liter): Beef extract 2g Soluble starch 1.5g Acid hydrolysis of casein 17.5g Final pH7.3 ± 0.2
How to use: 1.Suspend 21g in 1 L of distilled water , stirring heated to boiling until completely dissolved, dispensing flask, 121 autoclave for 15min. 2.Diluted and treated samples.
Storage: Keep container tightly closed, store in a cool, dry place, away from bright light. Storage period of 3 years.
DBCO-PEG4-PABA is an analog of DBCO-Acid with PEG linker and a 4-Aminobenzoic acid (PABA) group. The DBCO groups is commonly used for copper-free Click Chemistry reactions due to its strain promoted high energy. The hydrophilic PEG chain allows for increased water solubility. Reagent grade, for research use only.
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DBCO-PEG4-PABA is an analog of DBCO-Acid with PEG linker and a 4-Aminobenzoic acid (PABA) group. The DBCO groups is commonly used for copper-free Click Chemistry reactions due to its strain promoted high energy. The hydrophilic PEG chain allows for increased water solubility. Reagent grade, for research use only.
