Name: Magnetic Nanoparticles with Carboxyl Groups (100 -200 nm)
Brand: Molecular Depot
SKU: B2013581
Price: 795.00 USD
Availability: InStock

<h2>What are magnetic particles and beads used for in protein purification?</h2>
<p>&nbsp;</p>
<p>Magnetic particles and beads for protein applications are surface-functionalized magnetic microspheres designed for affinity-based purification of proteins and antibodies. Common chemistries include Protein A, Protein G, and Protein L coatings for antibody capture, Ni-NTA or Co-NTA surfaces for purification of His-tagged recombinant proteins, and streptavidin-coated beads for binding biotinylated targets. These systems use a magnetic stand or plate to enable gentle, column-free separation of bound proteins from lysates. Related entities include immunoprecipitation (IP) and co-immunoprecipitation (Co-IP), His-tag affinity purification, antibody cross-linking strategies to prevent antibody contamination in eluates, and magnetic separation systems.</p>
<p>&nbsp;</p>
<h2>What you will find:</h2>
<p>&nbsp;</p>
<ul>
<li>Functionalized Capture Spheres: Surface-modified magnetic particles engineered with specific chemical groups to secure target proteins, nucleic acids, or antibodies directly from complex lysates.</li>
<li>Affinity-Purified Matrices: High-selectivity magnetic supports pre-coupled with biological ligands to isolate specific molecular fractions while minimizing non-specific background binding.</li>
<li>High-Throughput Separation Cores: Calibrated paramagnetic clusters optimized to respond rapidly to magnetic plates, ensuring quick processing times and high yield consistency.</li>
</ul>
<p>&nbsp;</p>
<h2>How to choose magnetic particle and bead products</h2>
<p>&nbsp;</p>
<p><strong>Protein A vs. Protein G vs. Protein L</strong></p>
<p>Protein A binds IgG antibodies from many species but with variable affinity depending on subclass. Protein G provides broader and often stronger binding across a wider range of species and IgG subclasses. Protein L binds immunoglobulins through the kappa light chain rather than the Fc region, allowing it to capture a broader range of antibody classes such as IgG, IgM, IgA, IgE, and IgD. Selection depends on the species and antibody type being used in the experiment.</p>
<p><strong>His-tag purification: Ni-NTA vs. Co-NTA chemistry</strong></p>
<p>Ni-NTA magnetic beads (nickel-based) are widely used for His-tagged protein purification and generally offer higher binding capacity and yield. Co-NTA (cobalt-based) beads typically provide higher specificity and cleaner eluates by reducing non-specific binding of histidine-rich host proteins, but may result in slightly lower overall yield. The choice depends on whether yield or purity is the priority.</p>
<h3>IP vs. Co-IP cross-linking considerations</h3>
<p>In standard immunoprecipitation, antibodies are incubated with Protein A/G beads and lysate to capture target proteins. However, antibodies may co-elute with the target protein during elution and interfere with downstream analysis such as Western blotting. Cross-linking the antibody to the beads before incubation prevents antibody contamination in the eluate and improves downstream detection clarity.</p>
<h3>Streptavidin bead applications beyond standard IP</h3>
<p>Streptavidin-coated magnetic beads rely on the strong streptavidin&ndash;biotin interaction to capture biotinylated antibodies, proteins, nucleic acids, or probes. This expands their use beyond conventional immunoprecipitation into applications such as pull-down assays, proximity labeling workflows, and nucleic acid capture strategies.</p>
<p>&nbsp;</p>
<h2>Specifications context</h2>
<p>&nbsp;</p>
<p>Magnetic protein purification beads are typically characterized by binding capacity (for example, milligrams of IgG or His-tagged protein bound per milliliter of bead suspension) and particle size, often in the 1&ndash;3 micron range for many immunoprecipitation workflows. Different bead chemistries require specific elution conditions, such as low pH buffers for Protein A/G systems or imidazole gradients for Ni-NTA systems.</p>
<p>This sub-category is part of MBP's microbeads catalog alongside silica beads, which use similar magnetic separation principles for nucleic acid purification rather than protein isolation. For mechanical disruption workflows prior to extraction, researchers may also use glass beads or zirconium beads. MBP's specialist team can help confirm bead chemistry compatibility with a specific target protein, antibody species, or tagging system before order placement.</p>
<p><a href="https://mbpinc.net/contact-us"><strong>Contact the helpful team</strong></a> at MBP today to request a quote.</p>

Magnetic Particles & Beads

Molecular Depot

Key Specifications

Magnetic Nanoparticles with Carboxyl Groups (100 -200 nm)

<p>Magnetic Nanoparticles with Carboxyl Groups (100 -200 nm) by Molecular Depot is a suspension of 100 to 200 nm magnetic nanoparticles bearing carboxyl groups, at 1% solids. Carboxyl groups give a negative surface charge, keep the particles dispersed and couple to amines through carbodiimide chemistry. They are used to immobilize proteins and nucleic acids for magnetic separation, immunoprecipitation and affinity capture. Each unit contains 1 mL. MBP supplies Molecular Depot research reagents to research labs in the United States, Canada and worldwide.</p>