Name: Red Polystyrene Particles with Carboxyl Groups (200 nm)
Brand: Molecular Depot
SKU: B2013347
Price: 795.00 USD
Availability: InStock

<h2 data-section-id="1f6co2r" data-start="0" data-end="47">What are latex particles and beads used for?</h2>
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Latex particles and beads are monodisperse polystyrene microspheres with a well-characterized refractive index of approximately 1.59, commonly used to calibrate flow cytometers and other particle-analysis instruments by correlating light scatter signals with particles of known size. Fluorescent latex beads are additionally assigned standardized fluorescence values, such as molecules of equivalent soluble fluorophore (MESF), allowing fluorescence intensity measurements to be compared across different instruments and experiments. Related entities include flow cytometer calibration, light scatter-to-size correlation, MESF and ERF fluorescence standardization, and surface-functionalized particles used in bead-based immunoassays.
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<h2 dir="ltr">What you will find:</h2>
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Diagnostic Agglutination Spheres: High-stability latex particles engineered to cross-link visibly in the presence of specific target analytes, providing clear qualitative and quantitative readouts.
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Instrument Calibration Standards: Precision-sized polystyrene beads tailored to calibrate flow cytometers, particle counters, and microscopes for accurate size verification.
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Custom Surface Suspensions: Unmodified latex carriers optimized for physical adsorption of custom proteins or antigens, allowing flexible assay design and developmental freedom.
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<h2 data-section-id="x7cdyq" data-start="970" data-end="1019">How to choose latex particle and bead products</h2>
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Particle size range
Calibration beads are commonly available in diameters ranging from approximately 0.5 to 20 microns. Beads between 2 and 8 microns are frequently used for flow cytometry calibration because they are similar in size to many leukocyte populations. The appropriate bead size should be selected based on the cell or particle population being analyzed.
Plain vs. fluorescent calibration beads
Plain, non-fluorescent latex beads are used primarily for calibrating light scatter parameters and establishing particle size references. Fluorescent latex beads contain dyes such as fluorescein or phycoerythrin and are used to calibrate fluorescence channels, verify instrument performance, and assign standardized fluorescence values such as MESF.
Surface-functionalized beads for immunoassays
Latex beads may be coated with antibodies, proteins, streptavidin, or other surface molecules that allow them to function as solid supports in bead-based immunoassays and agglutination assays. The coating should be selected according to the intended target analyte and assay format.
Monodispersity and lot-to-lot consistency
Accurate instrument calibration depends on highly uniform particle populations. Reviewing bead diameter specifications, coefficient of variation values, and lot-specific certificates of analysis helps ensure reproducible calibration results across experiments and over time.
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<h2 data-section-id="1fljvas" data-start="3392" data-end="3417">Specifications context</h2>
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Latex calibration beads are characterized by precisely defined particle diameters and documented coefficients of variation that indicate size uniformity. Polystyrene latex particles typically have a refractive index of approximately 1.59, making them suitable for light scatter calibration applications. Fluorescent variants include assigned values in standardized units such as MESF or equivalent reference fluorophore (ERF), often traceable to recognized reference standards. Products are available in formats ranging from small laboratory calibration vials to larger quantities used in routine quality-control programs.&nbsp;
This sub-category is part of MBP's microbeads catalog alongside nanoparticles, which are commonly used for separation, labeling, and targeted particle-based applications. Laboratories performing mechanical sample disruption can also review glass beads and zirconium beads. MBP's specialist team can help confirm bead size, fluorescence standards, and surface functionalization requirements for a specific flow cytometer or assay workflow before order placement.
<a href="https://mbpinc.net/contact-us">Contact the helpful team</a> at MBP today to request a quote.

Latex Particles & Beads

Molecular Depot

Key Specifications

Red Polystyrene Particles with Carboxyl Groups (200 nm)

Red Polystyrene Particles with Carboxyl Groups (200 nm) by Molecular Depot is a suspension of 200 nm red-dyed polystyrene particles bearing carboxyl groups. A dyed particle with a coupling surface can be both tracked optically and conjugated to a capture protein. They are used as coloured tracer particles in uptake and flow studies and as coupling supports in bead assays and lateral flow tests. Each unit contains 0.5 mL. MBP supplies Molecular Depot research reagents to research labs in the United States, Canada and worldwide.