Long ssDNA Gel Extraction Kit for 10kb
Cat. No. DS650
Store Stable at 15 to 25℃ for 24 months from the date of receipt
Size 25 tests
high-quality, with low mechanical degradation and without ultraviolet light-induced damage from the purification process. The purified long ssDNA is suitable for molecular biology and biotechnology applications.
The Long ssDNA Preparation Kit can be universally used for purification and clean-up of long ssDNA.
Features and Specifications:
- Optimized for long ssDNA.
- High recovery yield (typically 55-75%).
- High purity.
- Low mechanical degradation.
- No UV light-induced DNA damage.
- Direct monitoring of the migration of long ssDNA blue bands in the gel during electrophoresis.
- Excision of long ssDNA under ambient light.
- Guanidine thiocyanate is used as chaotropic salts. NaI is not used.*
- ssDNA size for excision: 3,000 - 10,000 bases.
- Binding capacity on a Spin Column for ssDNA binding is up to 10μg.
- Elution volume: ≥ 15 μl.
- Residual NaI may be difficult to remove, and reduces the efficiency of downstream enzymatic reactions.
Caution! Wear gloves and protective clothing while handling the Crystal Violet.
Kit Components: 25 reactions
|Crystal Violet Solution||Crystal Violet 4mg/ml (2,500 x).||5 ml|
|Gel-Dissolving Buffer||It contains guanidine thiocyanate as chaotropic salts.||45 ml|
|Wash Buffer 1||Tris-base buffer
(Add 45 ml of 100 % ethanol to the Wash Buffer before use.)
|Wash Buffer 2||Tris-base buffer
(Add 45 ml of 100 % ethanol to the Wash Buffer before use.)
|Elution Buffer||10 mM Tris-HCl, pH 8.0.||5 ml|
|Spin Column||25 pieces|
- Ethanol and isopropanol are required for the product.
- If precipitated material has formed in Gel-Dissolving Buffer, heat to dissolve at 37℃.
- Heat block are required for 50-70℃ incubation.
- Denaturing Gel-Loading Buffer is required for the agarose gel electrophoresis of long ssDNA. It is not included in the kit. It can be purchased individually from BioDynamics Laboratory Inc. (see “Related Products“ on page 4).
STEP 1: Preparation of agarose gel containing Crystal Violet
An example of this is given for making 100 ml of a 0.8% agarose gel
STEP 2: Agarose gel electrophoresis and excision
A simple way is shown in the following example.
*3 Electrophoresis at a low temperature is recommended (less than 20℃). It gives a better resolution and strong Crystal Violet staining. If the temperature of gel and running buffer exceeds 25℃, Crystal Violet staining of long ssDNA becomes weak. If so, the gel can be restained by gentle shaking in a dilute Crystal Violet solution (40 μl of Crystal Violet Solution / 100 ml of water) for 0.5 to 1 hour after electrophoresis.
*4 To keep the gel temperature low during electrophoresis in a draft chamber, we recommend placing the electrophoresis apparatus on ice in an ice bucket.
*5 At least, use a pre-chilled 1xTAE running buffer on ice to keep a low temperature.
*6 Denaturing Gel-Loading Buffer is not included in the kit. It can be purchased individually from BioDynamics Laboratory Inc. (see “Related Product “on page 4)
*7 Desalting of the long ssDNAs sample (or the nicked plasmid) solution in advance is important for agarose gel electrophoresis. If the long ssDNAs sample (e.g. the nicked plasmid) solution contains excessive salt and Mg+2 , it adversely affects denaturation, resulting in giving poor bands and low recovery yields of the long ssDNA of interest. If your long ssDNA band is extremely weak, first you should consider the existence of residual salt in the long ssDNAs sample (or the nicked plasmid) solution. We recommend removing the salt in the long ssDNAs sample through ethanol precipitation. Importantly, wash with 70% ethanol twice, vortex vigorously during washing.
8 To get a highly purified long ssDNA, the long ssDNA of interest should be loaded greater than 0.5μg/band. At the same time, the concentration of the nicked plasmid in the loading sample should be under 0.25 μg/μl after mixing with the Denaturing Gel-Loading Buffer.
*9 The heating and cooling procedure of the long ssDNAs sample (e.g. the nicked plasmid) mixture should be carried out just before loading into wells of the gel.
*10 Do not load a sample too much in a well because it may overflow and cause contamination. It is recommended to make deep wells with thick gel.
*11 Long ssDNA bands moving in Crystal Violet-containing gel can be directly seen under ambient light in real time during electrophoresis. The electrophoresis can be stopped as soon as the bands are sufficiently resolved.
*12 Because crystal violet (positively-charged molecule) migrates toward the cathode, the dye concentration of the running buffer and the gel on the anode side gradually decreases. Check the dye concentration and if needed, add dye into the running buffer on the anode side during electrophoresis (e.g. 25 μl of Crystal Violet Solution is added to 250ml running buffer on the anode side every 30 min at 100V constant voltage).
*13 The long ssDNA band can be visible as a blue band and can be easily excised from the agarose gel on the bench.
*14 Minimize the size of the gel slice by removing extra agarose.
*15 The pLSODN (6 kb Fragment) and pLSODN (10 kb Fragment) were constructed by inserting a 6 kb fragment and a 10 kb fragment of DNA into cloning site of 13 kb plasmid and 20 kb plasmid, respectively. The double-nicked plasmids were obtained by double digestion with Nt.BspQI and Nb.BbvCI. The double-nicked The pLSODN (6 kb Fragment) gives mainly two linear ssDNAs (6 kb and 13 kb) and one circular ssDNA (19 kb). Similarly, the double-nicked The pLSODN (10 kb Fragment) gives two linear ssDNAs (10 kb and 20 kb) and one circular ssDNA (30 kb).
STEP 3: DNA extraction and purification
- Add 45 ml of 100 % ethanol to Wash Buffer 1 and Wash Buffer 2 bottles, respectively.
- Isopropanol is required in the step.
- All centrifugation steps should be carried out at 16,000×g (around 13,000 rpm in a conventional microcentrifuge) at room temperature (20℃- 25℃). Centrifugation at lower temperature might affect long ssDNA yield.
- This kit can also be used for long ssDNA clean-up from enzymatic reactions. For this purpose, add 3 volumes of Gel-Dissolving Buffer and 1 volume of isopropanol to the reaction, mix well, and proceed with step 5 of the protocol.
*2 If the volume of dissolved sample exceeds 500 μl, the loading of the sample onto the column should be performed in multiple rounds not to exceed 500 μl.
*3 Don’t flip the Collection Tube to discard the flow-through. It contaminates the edge and upper inner wall of the Collection Tube. Use a 1 ml pipette tip to discard the flow-through.
*4 Be careful to ensure the column tip does not contact column flow-through. If possible, we recommend using a new Collection Tube at several washing steps to avoid contamination. However, spare collection tubes are not included in the kit. They can be purchased from many companies (e.g. Corning Axygen #MCT-200-NC).
*5 Don’t wash the Spin Column with Gel-Dissolving Buffer only.
*6 Typical elution volumes are 15μl -40μl. Water can be used to elute the long ssDNA. The average elution volume is 36.5 μl from 40 μl Elution Buffer volume, and 12 μl from 15 μl.
*7 The total yield of ssDNA recovery from a 6 μg of a nicked plasmid pLSODN (6 kb Fragment) or pLSODN (10kb Fragment) was about 1.2 μg (100% recovery is 2 μg) using one column of the Long ssDNA Gel Extraction Kit for 10 kb with 40 μl Elution Buffer.