Gel Electrophoresis Reagents

Agarose

<h2>What is agarose for gel electrophoresis?</h2>
&nbsp;
Agarose is a linear polysaccharide derived from agar that, when dissolved in hot buffer and allowed to cool, forms a porous gel matrix whose pore size is determined by the agarose concentration. DNA and RNA molecules migrate through this matrix under an electric field at a rate inversely related to their size, allowing fragments of different lengths to be separated and visualized as distinct bands.
&nbsp;
<h2 dir="ltr">What you will find:</h2>
&nbsp;
<ul>
<li dir="ltr" role="presentation">Azura Agarose for routine electrophoresis of nucleic acids with low electroendosmosis (EEO) performance</li>
<li dir="ltr" role="presentation">Benchmark Agarose for PCR product analysis and high-quality nucleic acid separation</li>
<li dir="ltr" role="presentation">Benchmark Specialty Agarose for specialized gel applications requiring enhanced resolution and performance control</li>
<li dir="ltr" role="presentation">Standard Agarose for routine use in gel electrophoresis workflows</li>
<li dir="ltr" role="presentation">EZ Pack&trade; Agarose Tablets for agarose concentration control and convenient gel preparation&nbsp;</li>
</ul>
&nbsp;
<h2>How to choose agarose type and concentration</h2>
&nbsp;
Use standard agarose at 0.7&ndash;1% for routine PCR and restriction digest checks on larger fragments
A 0.7&ndash;1% standard agarose gel is commonly used for routine PCR product verification and restriction digest analysis when fragments are generally in the 1&ndash;10 kb size range.
Use 1.5&ndash;2% standard agarose for resolving smaller fragments in the 200 bp&ndash;2 kb range
Higher agarose concentrations from 1.5% to 2% are appropriate for resolving smaller PCR products, SNP genotyping amplicons, or restriction digests where size differences below 500 bp need to be clearly distinguished.
Use high-resolution agarose at 2&ndash;4% for very small fragments or close sizing
High-resolution agarose formulations can differentiate closely sized DNA fragments in the 50&ndash;500 bp range more effectively than standard agarose, making them useful for applications such as microsatellite or STR analysis.
Choose low-melting-point agarose when you need to recover DNA from gel slices
Low-melting-point (LMP) agarose can be melted at approximately 65&deg;C after electrophoresis, allowing DNA-containing gel slices to be processed more easily for downstream enzymatic reactions or purification workflows.
Confirm agarose purity (EEO grade) for sensitive applications
Electro-endosmosis (EEO) reflects agarose purity. Low-EEO agarose supports more consistent DNA migration and helps minimize contaminants that may interfere with downstream PCR amplification, restriction digestion, or other enzymatic applications.
&nbsp;
<h2>Specifications context</h2>
&nbsp;
Standard agarose gels are typically prepared by dissolving agarose powder in TAE or TBE buffer through heating, followed by cooling to approximately 55&deg;C before pouring into casting trays. Higher-concentration gels solidify more rapidly and generally benefit from prompt casting.
As of 2026, low-EEO agarose grades remain the preferred choice for sensitive applications such as Southern blotting, gel extraction followed by PCR, and restriction enzyme digestion workflows where contaminants can inhibit downstream reactions.
<a href="https://mbpinc.net/contact-us">Contact the expert team</a> and get premium agarose gel for your research today.

Azura Agarose LE

A1701Z by Azura Genomics is a highly purified, molecular biology-grade agarose powder refined using a solvent-free process, yielding DNase-, RNase-, and Protease-free agarose suitable for analytical and preparative nucleic acid electrophoresis across the 150 bp to 6 kb range.

Gel strength

Gel temperature

Melt temperature

EE0 (-mr)

Moisture content

Sulfate

Storage conditions

Manufacturer

Azura Agarose LE 100g

Azura Agarose LE 2 x 100g

Azura Agarose LE 2 x 500g

1Kb DNA Ladders

<h2>What is a 1 kb DNA ladder?</h2>
&nbsp;
A 1 kb DNA ladder is a gel electrophoresis size standard containing a defined set of double-stranded DNA fragments spaced at or near 1-kilobase intervals, produced by digesting proprietary plasmids with restriction enzymes to generate typically 10 or more bands spanning 0.5 to 10 kb. One band, commonly at 3.0 kb, is supplied at higher concentration to serve as a bright reference band for rapid gel orientation. The 1 kb ladder is one of the most widely used size standards for routine molecular biology applications, covering the size range commonly encountered in PCR products, restriction digests, and cloned inserts.
&nbsp;
<h2 dir="ltr">What you will find:</h2>
&nbsp;
<ul>
<li dir="ltr" role="presentation">ZR 1 kb DNA Marker for gel electrophoresis analysis and routine DNA fragment sizing&nbsp;</li>
<li dir="ltr" role="presentation">Azura PureView&trade; 1kb DNA Ladder for the detection of DNA bands with high visibility in agarose gel systems</li>
<li dir="ltr" role="presentation">1kb Plus Opti-DNA Marker for cloning verification workflows and a wide range of DNA fragment analysis&nbsp;</li>
<li dir="ltr" role="presentation">1kb Opti-DNA Marker used in nucleic acid analysis and PCR for standard molecular weight reference&nbsp;</li>
<li dir="ltr" role="presentation">Accuris SmartCheck&trade; 1kb DNA Ladder for quality assessment of gel and DNA sizing with high precision</li>
<li dir="ltr" role="presentation">1 KB DNA Marker for routine DNA electrophoresis&nbsp;</li>
</ul>
&nbsp;
<h2>How to choose a 1 kb DNA ladder variant</h2>
&nbsp;
Choose a standard 1 kb ladder for routine PCR and restriction digest analysis
A standard 1 kb ladder with fragments spanning approximately 0.5 to 10 kb is suitable when most expected DNA fragments fall within this range, making it ideal for routine PCR verification and restriction digest analysis.
Choose a 1 kb Plus ladder when samples include smaller fragments below 500 bp
The 1 kb Plus format extends coverage down to 100 bp while maintaining the upper size range, making it useful when both small PCR products and larger DNA fragments need to be analyzed on the same gel.
Choose a 1 kb Extend ladder when samples include very large DNA fragments
The 1 kb Extend ladder expands coverage up to approximately 48.5 kb and is appropriate for large plasmids, BAC clones, and other high-molecular-weight DNA fragments analyzed on low-percentage agarose gels.
Use the recommended loading volume for accurate mass estimation
Loading the ladder according to the manufacturer's recommended amount helps ensure that any provided band mass references can be used for approximate comparison of DNA quantity based on staining intensity.
Confirm the tracking dye is compatible with your staining and imaging setup
Different ladder formulations use different tracking dyes. Some dyes may partially obscure nearby bands under UV visualization, while alternative formulations are designed to minimize interference and improve visibility across the entire ladder range.
&nbsp;
<h2>Specifications context</h2>
&nbsp;
Standard 1 kb DNA ladders are generated from defined DNA templates digested to produce fragments of known sizes. Enhanced-intensity reference bands are included to provide a readily identifiable orientation marker during gel analysis.
Ready-to-load 1 kb ladder formats with reduced-shadow tracking dyes are commonly used in routine agarose gel electrophoresis workflows because they simplify preparation and improve overall band visibility.
<a href="https://mbpinc.net/contact-us">Contact the expert team at MBP</a> to book high-quality 1Kb DNA Ladders for your lab today.

User Manual

MSDS

PureView Ladder - Product Sheet

Azura PureView™ 1kb DNA Ladder

AZ-1101 by Azura Genomics is the PureView 1kb DNA Ladder — a ready-to-load agarose gel marker with 13 bands from 250 to 10,000 bp and high-intensity reference bands at 1,000 and 3,000 bp. Load 5 µl per lane directly; stable at room temperature for up to 6 months.

PureView 1Kb DNA Ladder 100 Lanes

PureView 1Kb DNA Ladder 500 Lanes

PureView 1Kb DNA Ladder 1,000 Lanes

50bp DNA Ladders

<h2>What is a 50 bp DNA ladder?</h2>
&nbsp;
A 50 bp DNA ladder provides reference bands spaced at 50-base-pair intervals, most commonly covering 50 bp to 1000 bp (or up to 1500 bp in some extended formats), making it suitable for gel electrophoresis experiments where samples are very small DNA fragments that a 100 bp ladder cannot resolve accurately because 100 bp band spacing is too coarse. Common applications include microsatellite and STR genotyping, analysis of small restriction digest products, multiplex or nested PCR amplicons, and other short-fragment applications in the 50&ndash;500 bp range where precise size discrimination is needed.
&nbsp;
<h2>What you will find:</h2>
&nbsp;
<ul>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
ZR 50 bp DNA Marker for precise analysis of smaller DNA fragments&nbsp;
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
Azura PureView&trade; 50 bp DNA Ladder for high-resolution gel results in electrophoresis
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
Accuris SmartCheck&trade; 50bp DNA Ladder for size determination of PCR products
</li>
</ul>
&nbsp;
<h2>How to choose and use a 50 bp DNA ladder</h2>
&nbsp;
Use a 50 bp ladder when your fragments differ by less than 100 bp and are below 500 bp
The primary reason to use a 50 bp ladder over a 100 bp ladder is when your samples include fragments with size differences of less than 100 bp that need to be resolved, such as microsatellite alleles or closely-sized PCR amplicons from multiplex reactions.
Run small-fragment gels on 2&ndash;4% agarose or polyacrylamide for adequate resolution
High-percentage agarose (2&ndash;4%) or polyacrylamide gels are needed to resolve very small DNA fragments as distinct bands rather than all migrating together near the gel front, since standard 1% agarose does not provide sufficient resolution for fragments below approximately 200 bp.
Use a reference band at a convenient size for quick orientation
Many 50 bp ladders include a brighter reference band at a convenient, easy-to-remember size such as 250 bp or 500 bp, which serves as an anchor for identifying surrounding bands without counting from the well each time.
Confirm the 50 bp ladder's smallest band is detectable with your staining system
Very small DNA fragments, especially below 100 bp, can be difficult to detect or may run off the gel front quickly, and confirming that the ladder's smallest defined bands are visible under your staining and imaging setup helps ensure the full ladder range is usable.
Consider polyacrylamide gels for the highest resolution of fragments below 200 bp
Polyacrylamide gel electrophoresis provides substantially higher resolution than high-percentage agarose for fragments below 100&ndash;200 bp, making it the preferred format when single-base or very fine size discrimination is needed in this range, such as for SSR or STR genotyping.
&nbsp;
<h2>Specifications context</h2>
&nbsp;
Standard 50 bp DNA ladders typically cover from 50 bp to 1000 bp with bands at 50 bp intervals, and many include a brighter reference band at 250 bp or 500 bp for quick orientation. As of 2026, the 50 bp ladder remains the standard small-fragment size reference for microsatellite and STR genotyping workflows, whether on standard agarose or capillary electrophoresis platforms where defined size standards are loaded alongside samples.
<a href="https://mbpinc.net/contact-us">Contact the expert team of Molecular Biology Products Inc. (MBP)</a> and get premium-quality 50bp DNA ladders for your next experiment.

Product Literature

Azura PureView™ 50 bp DNA Ladder

PureView™ 50 bp DNA Ladder (AZ-1151) by Azura Genomics — 17 bands, 50–1,500 bp, 0.1 mg/mL. Ready-to-load with Orange G dye. Load 5 µl per lane. Room-temperature stable 6 months. Available in 100-, 500-, and 1,000-lane packs.

PureView 50bp DNA Ladder 100 Lanes

PureView 50bp DNA Ladder 500 Lanes

PureView 50bp DNA Ladder 1,000 Lanes

Loading Dye

<h2>What is gel loading dye?</h2>
&nbsp;
Gel loading dye, also called sample loading buffer or tracking dye, is a concentrated solution mixed with a DNA, RNA, or protein sample immediately before it is loaded into a gel well. It serves two essential functions: the density agent, typically glycerol at 30&ndash;60% or Ficoll, makes the sample denser than the running buffer so it sinks to the well bottom rather than diffusing back out; and the tracking dyes, most commonly bromophenol blue and xylene cyanol FF, provide visible colored bands that co-migrate at defined, approximate DNA equivalent sizes to allow the researcher to monitor migration progress and estimate when to stop the run.
&nbsp;
<h2 dir="ltr">What you will find:</h2>
&nbsp;
<ul>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
Azura SmartStain Loading Dye for the same preparation and loading
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
Safe-Red loading dye for visualization of nucleic acids in electrophoresis workflows
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
Safe-Green loading dye for gel analysis and DNA tracking applications
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
SmartGlow&trade; Loading Dye with Safe Green Stain for visualization and integrated sample loading
</li>
</ul>
&nbsp;
<h2>How to choose and use gel loading dye</h2>
&nbsp;
Use 6X loading dye at 1/6 volume of total sample volume
Most gel loading dyes are formulated as 6X concentrates so that adding one part loading dye to five parts sample brings the total volume to the final working concentration. For a 10 &micro;l final load, add 2 &micro;l of 6X loading dye to 8 &micro;l of DNA or RNA sample and mix well before loading.
Choose tracking dye colors that won't obscure your expected DNA band sizes
Bromophenol blue co-migrates with approximately 300&ndash;370 bp in a 1% TAE agarose gel, while xylene cyanol co-migrates with approximately 3,000&ndash;4,000 bp in the same conditions. If your samples are expected near those sizes, using a loading dye that includes orange G instead, which co-migrates below 50 bp, avoids masking bands with the tracking dye front.
Confirm EDTA is included if nuclease protection matters for your samples
A standard 6X loading dye contains 60 mM EDTA, which chelates divalent metal ions that nucleases require for activity, providing protection against DNA degradation during sample preparation and the gel run. If your protocol requires EDTA-free loading buffer, confirm the dye formulation before use.
For RNA samples, ensure your loading dye is RNase-free
RNase contamination in loading dye can degrade RNA samples during preparation before loading, so RNA gel experiments require either RNase-free certified loading dye or dye preparation from RNase-free reagents. Using the same nuclease-free water and handling precautions for loading dye as for the RNA samples themselves is standard practice.
Be aware that SDS-containing loading buffers for protein SDS-PAGE differ from nucleic acid loading dyes
SDS-PAGE protein loading buffers contain SDS, dithiothreitol or beta-mercaptoethanol as a reducing agent, and glycerol, which are specifically required for protein denaturation and separation under SDS conditions, whereas nucleic acid loading dyes contain no SDS or reducing agents. The two formulations are not interchangeable.
&nbsp;
<h2>Specifications context</h2>
&nbsp;
A standard 6X DNA loading dye formulation typically contains 10 mM Tris-HCl (pH 7.6), 0.03% bromophenol blue, 0.03% xylene cyanol FF, 60% glycerol, and 60 mM EDTA, making it compatible with both TAE and TBE running buffers. As of 2026, ready-to-use loading dyes pre-mixed as part of ready-to-load DNA ladder products remain popular for eliminating the need for a separate mixing step before gel load
<a href="https://mbpinc.net/contact-us">Contact the expert team at MBP</a> to obtain high-quality DNA loading dyes for your research workflows.

Azura SmartStain Loading Dye 1ml

AZ4500-LDZ by Azura Genomics is a 1 mL, 6× agarose gel loading dye with integrated SmartStain™ that detects as little as 0.1 ng DNA, excites at both 290 nm and 490 nm for UV and blue-light imaging, and eliminates the need for separate EtBr gel staining.

Pre-Stain/Casting

<h2>What is pre-stain/casting in gel electrophoresis?</h2>
&nbsp;
Pre-staining is the practice of incorporating a fluorescent DNA-intercalating dye into molten agarose before it is poured into the gel tray and allowed to solidify, so that when DNA migrates through the gel under the electric field, bands become fluorescent as the DNA molecules bind dye molecules pre-distributed throughout the matrix. This approach allows bands to be monitored by UV or blue-light visualization during the run and eliminates the separate post-run soaking step that post-staining requires.
&nbsp;
<h2 dir="ltr">What you will find:</h2>
&nbsp;
<ul>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
Azura SmartStain Pre-Stain for visualization of DNA during gel casting
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
SmartGlow&trade; Safe Green Pre-Stain for DNA/RNA detection in gels
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
BlinkBlue&reg; SDS-PAGE Staining Buffer for gel analysis of proteins
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
SafeView Classic gel stain for day-to-day nucleic acids visualization during electrophoresis
</li>
</ul>
&nbsp;
<h2>How to choose and use pre-cast gel stains</h2>
&nbsp;
Add ethidium bromide at the standard concentration when safety constraints allow
Ethidium bromide, the classic pre-cast stain, is typically added to cooled, molten agarose at approximately 0.5 &micro;g/ml before pouring, providing excellent sensitivity with standard UV transilluminator imaging. Its mutagenicity requires standard handling precautions and specific waste disposal practices.
Substitute GelRed or SYBR Safe for a safer pre-cast stain option
GelRed and SYBR Safe can both be incorporated into molten agarose before casting as direct ethidium bromide substitutes at the manufacturer's recommended working concentrations, using standard UV (GelRed) or UV/blue light (SYBR Safe) for visualization on the same equipment.
Be aware that GelRed precast gels can affect DNA migration in some samples
GelRed's larger molecular size means it can cause abnormal band migration in precast gels for some samples, notably restriction digest products, compared with ethidium bromide precast gels, and this is why GelRed is specifically recommended for post-staining rather than pre-casting when migration accuracy matters most.
Cool agarose to approximately 55&ndash;60&deg;C before adding heat-sensitive staining reagents
Some intercalating dyes degrade or lose activity at the temperatures used to keep agarose liquid for pouring, and adding stain only after the agarose has cooled to approximately 55&ndash;60&deg;C, just before pouring, ensures consistent staining without heat-induced dye degradation.
Use blue-light gel imaging for downstream DNA recovery from pre-stained gels
If DNA will be excised from a pre-stained gel for downstream use, UV light should be minimized during excision because UV irradiation can introduce pyrimidine dimers and other photodamage that reduces downstream enzymatic efficiency. GelRed and SYBR Safe pre-cast gels can be imaged with a blue or amber light system to avoid this damage.
&nbsp;
<h2>Specifications context</h2>
&nbsp;
When ethidium bromide is used as a pre-cast stain, the positively charged EtBr molecules migrate toward the negative electrode during electrophoresis, moving out of the gel over time into the running buffer, which means the gel is effectively self-destaining during the run and background is reduced without a separate destaining step. As of 2026, EtBr-free labs most commonly use GelRed in post-staining applications for its superior sensitivity, while SYBR Safe is widely used as a pre-cast stain in labs that prioritize downstream DNA compatibility and blue-light gel excision.
<a href="https://mbpinc.net/contact-us">Contact the expert team at MBP</a> to get the right pre-staining/casting solutions for your lab.

Azura SmartStain Pre-Stain 1ml

AZ4500-PSZ by Azura Genomics: 1 ml EtBr-alternative nucleic acid pre-stain for agarose gels. Excitation at 290 nm (UV) and 490 nm (blue light). Detects 0.1 ng DNA. Green fluorescence for DNA, red for RNA. No post-run destaining required.

100bp DNA Ladders

<h2>What is a 100 bp DNA ladder?</h2>
&nbsp;
A 100 bp DNA ladder provides reference bands at 100-base-pair intervals, typically covering 100 bp to 1000 bp or 100 bp to 2000 bp depending on the variant, making it the most commonly used size standard for routine sizing of small PCR amplicons and restriction digest products. Most commercially available 100 bp ladders include a brighter reference band at 500 bp or 600 bp for quick orientation, and many are available in ready-to-load formats pre-mixed with loading dye and glycerol for direct pipetting into gel wells.
&nbsp;
<h2 dir="ltr">What you will find:</h2>
&nbsp;
<ul>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
ZR 100 bp DNA Marker (M5002-200) for high-resolution sizing of DNA fragments in routine electrophoresis workflows
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
PureView 100bp DNA Ladder for precise sizing and enhanced band visualization of small DNA fragments
</li>
</ul>
&nbsp;
<h2>How to choose and use a 100 bp DNA ladder</h2>
&nbsp;
Use a 100 bp ladder when your samples are mostly below 2 kb
A 100 bp ladder provides more resolution than a 1 kb ladder in the small-fragment range, since 100 bp spacing gives reference bands every 100 bp rather than every 1000 bp. If samples span a broader size range, the 1 kb Plus ladder extending down to 100 bp may be a more versatile single-ladder choice.
Run small-fragment gels on 1.5&ndash;2% agarose for best resolution
Fragments in the 100&ndash;500 bp range benefit from 1.5&ndash;2% agarose, which gives tighter, better-defined bands in this small-fragment window and reduces the risk of small bands reaching the gel front before larger fragments are adequately separated.
Look for a 500 bp or 600 bp reference band for easy orientation
Most 100 bp ladders include a brighter band at a convenient midpoint like 500 bp or 600 bp, which serves as a visual anchor for counting up or down in 100 bp intervals to identify the nearest ladder band.
Choose between upper ranges (1000 bp vs 2000 bp) based on sample sizes
Some 100 bp ladders cover only to 1000 bp (10 bands), while extended versions cover up to 2000 bp. If samples occasionally include products above 1000 bp, the extended range provides coverage without switching to a separate 1 kb ladder.
Pair with a 1 kb ladder when samples span both large and small size ranges
If an experiment includes both small PCR amplicons around 100&ndash;500 bp and larger restriction fragments above 2 kb, loading both a 100 bp and a 1 kb ladder in adjacent lanes provides accurate reference coverage across the full size range.
&nbsp;
<h2>Specifications context</h2>
&nbsp;
The 100 bp DNA ladder is one of the two most commonly used DNA size standards in routine molecular biology labs, alongside the 1 kb ladder, and most labs running small PCR products routinely keep a 100 bp ladder on hand. As of 2026, ready-to-load 100 bp ladder formats with a 500 bp or 600 bp bright reference band remain the default choice for routine agarose gel electrophoresis of small PCR products and restriction digest fragments.
<a href="https://mbpinc.net/contact-us">Contact the expert team at MBP</a> for assistance in selecting the right 100bp DNA ladder for your lab.

PureView 100bp DNA Ladder

AZ-1131 by Azura Genomics — PureView™ 100bp DNA Ladder, 11 bands 100 bp–1.5 kb, dual high-intensity reference bands at 500 bp and 1.5 kb, 0.1 mg/mL, 5 µL/lane, ready-to-load. Stable at 25°C for 6 months. Available in 100, 500, and 1,000-lane packs.

PureView 100bp DNA Ladder 100 Lanes

PureView 100bp DNA Ladder 500 Lanes

PureView 100bp DNA Ladder 1,000 Lanes

2Kb DNA Ladders

<h2>What is a 2 kb DNA ladder?</h2>
&nbsp;
A 2 kb DNA ladder provides reference bands spaced at approximately 2-kilobase intervals, designed for gel electrophoresis where samples include large DNA fragments and where 1-kilobase spacing between reference bands would crowd too many bands into the upper region of a low-percentage gel. These ladders are particularly useful when working with large restriction digest products, BAC or cosmid clone inserts, large plasmids, or genomic DNA fragments in the 2&ndash;20 kb size range, run on 0.5&ndash;0.8% agarose to give these large molecules room to resolve.
&nbsp;
<h2 dir="ltr">What you will find:</h2>
&nbsp;
<ul>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
PureView PCR DNA Ladder for routine analysis of gel and size estimation of PCR product&nbsp;
</li>
<li dir="ltr" style="font-family: arial, helvetica, sans-serif;" aria-level="1">
2kb Opti-DNA Marker for accurate sizing of DNA fragments in gel electrophoresis&nbsp;
</li>
</ul>
&nbsp;
<h2>How to choose and use a 2 kb DNA ladder</h2>
&nbsp;
Use a 2 kb ladder when your samples are predominantly in the 2&ndash;20 kb size range
If most of your samples are in the multi-kilobase range, 2 kb spacing gives each reference band more separation on the gel, making it easier to estimate size in a region where 1 kb reference bands would be compressed together.
Run large-fragment gels on 0.5&ndash;0.8% agarose for adequate resolution
Standard 1% agarose does not give sufficient resolution for DNA fragments above 10 kb, and low-percentage gels of 0.5&ndash;0.8% provide the larger pore size needed for large molecules to migrate and resolve as distinct bands rather than compressing together at the top of the gel.
Confirm your 2 kb ladder covers the upper size range of your samples
Like any DNA ladder, the 2 kb ladder's largest defined band should be at or above the largest fragment in your sample, since fragments larger than the ladder's upper limit cannot be sized against it and may run together at the well or upper gel.
Plan for longer electrophoresis run times with low-percentage gels
Large DNA fragments migrate slowly through gel matrices, and low-percentage gels run at typical voltages require longer run times to achieve adequate separation of bands across the size range covered by the ladder.
Use a 2 kb ladder alongside a 1 kb ladder when samples span a wide size range
If your samples include both small and large fragments, loading both a 2 kb ladder and a 1 kb ladder in adjacent lanes provides reference coverage across the full size range without either ladder being suboptimal for part of your sample set.
&nbsp;
<h2>Specifications context</h2>
&nbsp;
The compression of larger DNA bands in the upper gel region is a fundamental property of agarose electrophoresis: the relationship between fragment size and migration distance is non-linear, so bands in the upper kilobase range are closer together in migration distance than the same size difference produces in the lower range. The 2 kb increment addresses this by providing wider-spaced reference points where 1 kb spacing would produce visually crowded bands on a low-percentage gel. As of 2026, 2 kb ladders are most commonly used when gel conditions are deliberately optimized for large fragments, such as for BAC clone verification or genomic DNA fragment analysis.
<a href="https://mbpinc.net/contact-us">Contact the expert team at Molecular Biology Products Inc. (MBP)</a> to get high-quality 2Kb DNA ladders tailored for your research workflows.

PureView PCR DNA Ladder

AZ-1121 by Azura Genomics — PureView™ PCR DNA Ladder, 6 bands 100 bp–2.0 kb, 750 bp reference band, 0.1 mg/mL, ready-to-load (no extra buffer). Stable at room temp 6 months. Available in 100-, 500-, and 1000-lane packs.

PureView PCR DNA Ladder 100 Lanes

PureView PCR DNA Ladder 500 Lanes

PureView PCR DNA Ladder 1000 Lanes

Prestained Protein Ladders

<h2>What are prestained protein ladders?</h2>
&nbsp;
Prestained protein ladders are protein molecular weight standards in which each protein band carries a covalent colored dye, typically coupling most bands in blue with two specifically colored bands, often green around 25 kDa and red around 75 kDa, that serve as easily visible reference anchors for quick orientation. Because the dye is visible without staining, the ladder is used to monitor protein migration in real time during SDS-PAGE and, critically, to verify that protein bands have transferred from the gel to the PVDF, nitrocellulose, or nylon membrane before antibody incubation in western blotting.
&nbsp;
<h2 dir="ltr">What you will find:</h2>
&nbsp;
<ul>
<li dir="ltr" role="presentation">PureView&trade; Prestained Protein Ladder for clear visualization of&nbsp; bands in SDS-PAGE</li>
<li dir="ltr" role="presentation">SmartCheck&trade; Tri-color Extended Range Plus Protein Marker for broad coverage of protein size&nbsp;</li>
<li dir="ltr" role="presentation">Opti-Protein Marker for accurate molecular weight estimation of proteins</li>
<li dir="ltr" role="presentation">Opti-Protein XL Marker for wider range analysis of proteins&nbsp;</li>
<li dir="ltr" role="presentation">Opti-Protein Ultra Marker for efficient protein separation workflows</li>
</ul>
&nbsp;
<h2>How to use prestained protein ladders</h2>
&nbsp;
Load prestained ladders directly from the tube without preparation
Most modern prestained protein ladders are supplied in gel loading buffer and are ready to load directly without heating, dilution, or addition of reducing agent, since modifying the formulation can cause dye dissociation or protein aggregation. Following the manufacturer's specific note about preparation avoids introducing variability.
Confirm the ladder's kDa range brackets your target protein's expected molecular weight
Match your target protein's expected size to the ladder's coverage: a mid-range ladder (10&ndash;180 kDa) suits most antibody targets in typical western blot experiments, while a broad-range (10&ndash;245 kDa) or extra-broad (3.5&ndash;260 kDa) ladder is needed when the target protein is very large.
Use the colored reference bands for quick gel and blot orientation
Colored reference bands at fixed kDa positions, typically green at 25 kDa and red at 75 kDa, allow you to orient the ladder pattern on the gel or membrane at a glance without counting all bands from the well, making it fast to identify the bands bracketing your target protein.
Check the manufacturer's MW table calibrated for your specific SDS-PAGE buffer system
Pre-stained ladder proteins have apparent molecular weights that differ depending on the SDS-PAGE buffer system used, such as Tris-Glycine versus Bis-Tris MOPS or MES, because the buffer's pH and composition affect SDS binding and protein charge. Using the manufacturer's annotated molecular weight values calibrated for your specific buffer gives more accurate sizing than a generic table.
Verify western blot transfer by confirming the prestained bands are visible on the membrane
After transfer, all or most prestained ladder bands should be visible on the blot membrane; missing or faint bands in a particular region indicate incomplete transfer in that molecular weight zone, guiding troubleshooting before antibody incubation and detection.
&nbsp;
<h2>Specifications context</h2>
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Prestained protein ladders are loaded at approximately 3&ndash;5 &micro;l per lane for gel visualization during SDS-PAGE, or at 1.5&ndash;2.5 &micro;l per lane for western blot transfer, since less ladder per lane is needed for adequate band visibility on the membrane than for gel visualization. As of 2026, ready-to-load prestained protein ladder formats supplied pre-formulated in SDS-PAGE loading buffer that require no heating, dilution, or reducing agent remain the dominant format for routine SDS-PAGE and western blotting, since preparation-free direct loading eliminates one class of user handling errors.
<a href="https://mbpinc.net/contact-us">Contact the helpful team at Molecular Biology Products Inc. (MBP)</a> and find the best prestained protein ladders for your next experiment.

PureView™ Prestained Protein Ladder

PureView™ Prestained Protein Ladder (AZ-1141) by Azura Genomics — 13 pre-stained bands from 5–245 kDa (Tris-Glycine) with green 25 kDa and red 75 kDa reference bands. Ready-to-use, no heating required. Available in 500 µl to 5 ml pack sizes.