400nm Carboxyl Red-Fluo Microspheres CFR400-10

400nm Carboxyl Red-Fluo Microspheres CFR400-10

SHBC CFR400-10 are 400 nm carboxyl-functionalized red fluorescent microspheres developed for fluorescent immunoassays, lateral flow tests and biomolecule labeling.

With excitation at 535 nm and emission at 610 nm, the microspheres provide a clear red fluorescent signal. Surface carboxyl groups support covalent coupling of antibodies, antigens, proteins and other amino-containing biomolecules.

Product Specifications

Batch-specific particle size, particle size distribution, carboxyl content and fluorescence data are available in the Certificate of Analysis.

Red Fluorescence at 535/610nm

CFR400-10 can be excited using a 535 nm light source and produces red fluorescence centered at approximately 610 nm.

The optical profile is suitable for fluorescence readers, imaging systems and assay platforms equipped with compatible excitation and emission filters.

Key Advantages

Bright Red Fluorescent Signal

The 535/610 nm fluorescence profile provides a strong optical signal for qualitative and quantitative detection.

400nm Particle Size

The 400 nm diameter offers a balance between fluorescent signal intensity, surface coupling capacity and membrane migration.

Carboxyl-Functionalized Surface

Surface COOH groups support covalent immobilization of antibodies, antigens, proteins, peptides and other amino-containing molecules.

Uniform Particle Distribution

Controlled particle sizing supports repeatable conjugation, membrane flow and assay performance.

1% Ready-to-Use Suspension

The aqueous suspension is convenient for laboratory evaluation, conjugation development and production scale-up.

Custom and Bulk Supply

SHBC supports samples, customized specifications, pilot production and industrial batch supply.

Main Applications

Fluorescent Lateral Flow Immunoassays

CFR400-10 can be used as a fluorescent reporter particle in qualitative and quantitative lateral flow test strips.

Fluorescence Immunoassays

Suitable for sandwich, competitive and indirect fluorescent immunoassay formats.

Antibody and Antigen Conjugation

Surface carboxyl groups enable covalent immobilization of antibodies, antigens and recombinant proteins.

Infectious Disease Testing

Can be evaluated for fluorescent assays targeting viral, bacterial and other infectious disease biomarkers.

Cardiac and Inflammation Markers

Suitable for assay development involving cardiac biomarkers, inflammatory markers and other low-concentration analytes.

Food and Veterinary Testing

Can be used in fluorescent detection systems for food safety, veterinary diagnostics and agricultural testing.

Cell Labeling and Imaging

Suitable for selected cell-binding, particle uptake and fluorescence imaging studies.

Fluorescent Tracer Studies

Can be evaluated as a fluorescent tracer in membrane flow, filtration and particle transport research.

Benefits for Lateral Flow Assays

CFR400-10 provides several advantages for fluorescent lateral flow development:

• Visible red fluorescence

• High fluorescent signal per particle

• Active COOH coupling surface

• Suitable particle size for membrane-based assays

• Compatible with quantitative readers

• Potential for lower background than visible color detection

• Supports multiplex assay development

• Suitable for research and batch production

Membrane type, running buffer and conjugate release conditions should be optimized for the final assay.

Biomolecule Coupling

The carboxyl surface can be activated using EDC/NHS chemistry and coupled with primary amine groups on antibodies or proteins.

A typical coupling workflow includes:

1. Wash and disperse the microspheres.

2. Activate surface carboxyl groups with EDC and NHS.

3. Add the antibody or target protein.

4. Block remaining active sites.

5. Wash and resuspend the conjugated microspheres.

6. Evaluate fluorescence, coupling efficiency and assay performance.

Coupling conditions should be optimized for each biomolecule.

Assay Development Considerations

Important parameters include:

• Antibody-to-particle ratio

• EDC and NHS concentration

• Activation pH

• Coupling buffer

• Coupling time

• Blocking reagent

• Conjugate storage buffer

• Membrane pore size

• Running buffer composition

• Fluorescence reader settings

Optimization is recommended before scale-up.

Dispersion and Handling Guide

Before use:

• Allow the product to reach the required working temperature

• Mix by gentle inversion or controlled vortexing

• Avoid introducing excessive bubbles

• Do not allow the particles to dry

• Avoid repeated freeze-thaw cycles

• Protect the suspension from strong light

• Confirm compatibility before adding salts or organic solvents

Controlled sonication may be used when necessary to redisperse particles.

Membrane Flow Optimization

The 400 nm particle size can provide a strong signal but requires suitable membrane and buffer conditions.

Evaluate:

• Nitrocellulose membrane pore structure

• Sample viscosity

• Surfactant concentration

• Salt concentration

• Blocking formulation

• Conjugate pad release

• Particle aggregation

• Test-line capture density

Poor dispersion or unsuitable membrane conditions may reduce migration speed and increase background.

Custom Carboxyl Fluorescent Microspheres

SHBC can customize fluorescent microspheres according to assay requirements.

Available options may include:

• Custom particle size

• Custom excitation and emission wavelength

• Different fluorescence colors

• Carboxyl group density

• Solid content

• Dispersion buffer

• Particle concentration

• Surface modification

• Custom packaging

• OEM and ODM production

Please provide the application, target wavelength, particle size and required quantity when requesting customization.

Quality Control and Documents

Available documents may include:

• Certificate of Analysis

• Technical Data Sheet

• Safety Data Sheet

• Particle size report

• Particle size distribution data

• Fluorescence spectrum

• Carboxyl content data

• Microscopy images

• Batch inspection report

Why Choose SHBC?

Shanghai SanYu Biotechnology Co., Ltd. specializes in fluorescent microspheres, colored latex particles, magnetic beads and functional microsphere materials.

SHBC provides:

• Controlled microsphere manufacturing

• Stable particle size distribution

• Multiple fluorescence wavelengths

• Functional surface modification

• Batch-to-batch consistency

• Sample evaluation support

• Pilot and bulk production

• OEM and ODM services

Frequently Asked Questions

What is CFR400-10?

CFR400-10 is a 400 nm carboxyl-functionalized red fluorescent microsphere suspension with 1% solid content.

What are the excitation and emission wavelengths?

The excitation wavelength is 535 nm and the emission wavelength is 610 nm.

Is CFR400-10 suitable for lateral flow assays?

Yes. It can be evaluated as a fluorescent reporter particle in qualitative and quantitative lateral flow immunoassays.

What biomolecules can be coupled to CFR400-10?

Antibodies, antigens, proteins, peptides and other molecules containing primary amine groups can be coupled to the carboxyl surface.

Which coupling method is recommended?

EDC/NHS chemistry is commonly used to activate carboxyl groups for covalent protein coupling.

Can a 488nm laser excite CFR400-10?

The specified excitation wavelength is 535 nm. A 488 nm light source may not provide optimal excitation, so signal intensity should be tested with the actual instrument.

How should the product be dispersed before use?

Mix gently by inversion, controlled vortexing or compatible sonication while avoiding excessive foam and aggregation.

Can CFR400-10 be customized?

Yes. Particle size, fluorescence wavelength, carboxyl density, solid content, buffer and packaging can be customized.

Are samples and bulk quantities available?

Yes. SHBC supports laboratory samples, pilot orders and industrial batch production.

Request a Sample or Quotation

Contact SHBC for CFR400-10 samples, technical specifications, coupling support and bulk pricing.

Please provide:

• Target application

• Target biomarker

• Assay format

• Required quantity

• Preferred packaging

• Expected annual demand

Product: 400nm Carboxyl Red-Fluo Microspheres
Catalog Number: CFR400-10
Particle Size: 400 nm
Solid Content: 1%
Excitation/Emission: 535/610 nm
Surface Group: Carboxyl, COOH
Brand: SHBC
Manufacturer: Shanghai SanYu Biotechnology Co., Ltd.