Gold Colloid and Conjugates

Setting the Gold Standard for Nanoparticles

For three decades BBI has supplied the gold that powers more than 500 million diagnostic strips every year. making us the trusted partner for thousands of researchers, lateral flow assay developers and manufacturers worldwide.

World-renowned BBI Gold Colloid & Conjugates.

BBI’s optimized and proven production process yields citrate-capped nanospheres in sizes from 5nm up to 250nm with tight specifications in both size and %CV.  This uniformity yields high batch-to-batch reproducibility, improving end-user manufacturability, reducing waste, and increasing speed to market.  BBI’s large batch size, ISO-13485-certified manufacturing facility, and unparalleled quality results in a product with trusted performance year after year

Market-leading Gold Conjugates – Ready-to-run or Custom Solutions.

BBI specializes in conjugation to gold colloid.  Choose from off-the-shelf conjugates or bespoke conjugation service to meet your individual needs – both backed by stringent QC and expert technical support

Gold Colloid – In Vitro Diagnostic Applications

Product Name Code Type Applications
Gold Colloid: 20nm EM.GC20/7 Gold Colloid Lateral Flow Buy now
Gold Colloid: 40nm EM.GC40/7 Gold Colloid Biosensing, Lateral Flow, Microarray Buy now
Gold colloid: 60nm EM.GC60/7 Gold Colloid Biosensing, Lateral Flow, Microarray Buy now
Gold Colloid: 80nm EM.GC80/7 Gold Colloid Biosensing, Lateral Flow, Microarray Buy now
Gold Colloid: 100nm EM.GC100/7 Gold Colloid Biosensor Buy now
Gold Colloid: 150nm EM.GC150/7 Gold Colloid Biosensor Buy now

Conjugates

Product Name Code Type Applications
EM Grade 10nm BSA gold conjugate EM.BSA10/2 Gold Conjugate Electron Microscopy Buy now
EM Grade 15nm BSA gold conjugate EM.BSA15/2 Gold Conjugate Electron Microscopy Buy now
EM Grade 20nm BSA gold conjugate EM.BSA20/2 Gold Conjugate Electron Microscopy Buy now
EM Grade 40nm BSA gold conjugate EM.BSA40/2 Gold Conjugate Electron Microscopy Buy now

Brochures

Brochure

Gold Conjugate Starter Protocol

Protein conjugation can be complex, especially when developing a reproducible, scalable product.
Conjugation of proteins to gold depends upon three separate but dependent phenomena –

  • Ionic attraction between negatively charged gold and positively charged protein
  • Hydrophobic attraction between the protein and the gold surface
  • Dative binding between the gold conducting electrons and sulphur atoms which may occur within amino
    acids of the protein.

This protocol is a little bit of our expertise in a kit and is suitable for assessment of potential conjugation
conditions but is not necessarily suitable for production of conjugates at full manufacturing scale.

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Brochure

Products & Services

Inside this catalog you’ll find one of the industry’s broadest collections of enzymes, antibodies, antigens, and more – meticulously developed to power world-class diagnostics and keep your pipeline moving.

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Products and Services brochure

Brochure

Reagents Range

Discover our collection of reagents covering a comprehensive range of biomarkers and applications for the IVD market, life sciences, cell culture and beyond.

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Antibody Development

Antibody Development

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Autoimmunity Guidebook

Autoimmunity Guidebook

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Diabetes Brochure

Diabetes

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Frequently asked questions

Gold Colloid and Conjugates

Request a sample

Delivering exceptional quality gold, time after time

Uniformity 
High stability
Scalability
Quality

With ≤5% odd shapes and a CV of ≤8%, the uniform shape and size of BBI gold ensures even antibody binding, giving reliable results in your assay.

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BBI particles are proven stable for at 24 months and are supplied with a minimum of three month’s expiry. Stable particles ensure a settled testing regime, saving you time and wastage.

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Our batch sizes go up to 340l (40nm) to ensure you have a continuous supply.

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 BBI gold must pass strict quality procedures before it's released to our customers, guaranteeing impressive performance characteristics at scale.

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Gold Colloid in a flask Scientist running a test

Gold Colloid

Setting the Gold Standard for Nanoparticles

Every year our colloidal gold nanoparticles are used in over 500 million assays globally and are renowned for offering exceptional assay consistency levels. Our proprietary manufacturing technique allows for the production of large volume batches of gold to a high level of reproducibility of size, dispersion and shape, and we maintain this through tight quality control release specifications. This ensures a firm foundation for conjugation and peace of mind that your assay will provide reliable results.

BBI Solutions have been manufacturing high-quality gold nanoparticles for over 30 years, making us the trusted partner for thousands of researchers, lateral flow assay developers and manufacturers worldwide.

Scientists in a lab

Gold Colloid - Life Sciences

Product Name Applications Shelf Life
Gold Colloid: 5nm Biosensor, Electron Microscopy 24 months from Date of Manufacture Buy now
Gold Colloid: 10nm Biosensor, Electron Microscopy 24 months from Date of Manufacture Buy now
Gold Colloid: 15nm Biosensor, Electron Microscopy 24 months from Date of Manufacture Buy now
Gold Colloid: 20nm Lateral Flow 24 months from Date of Manufacture Buy now
Gold Colloid: 30nm Biosensor, Electron Microscopy 24 months from Date of Manufacture Buy now
Gold Colloid: 40nm Biosensing, Lateral Flow, Microarray 24 months from Date of Manufacture Buy now
Gold Colloid: 50nm Biosensing, Lateral Flow, Microarray 24 months from Date of Manufacture Buy now
Gold colloid: 60nm Biosensing, Lateral Flow, Microarray 24 months from Date of Manufacture Buy now
Gold Colloid: 80nm Biosensing, Lateral Flow, Microarray 24 months from Date of Manufacture Buy now
Gold Colloid: 100nm Biosensor 24 months from Date of Manufacture Buy now
Gold Colloid: 150nm Biosensor 24 months from Date of Manufacture Buy now
Gold Colloid: 200nm Biosensor 24 months from Date of Manufacture Buy now
Gold Colloid: 250nm Biosensor 24 months from Date of Manufacture Buy now

Gold Starter Packs

Are you using gold for the first time, or trying a new process and are unsure of which size particle to purchase? Our gold starter packs allow a comprehensive evaluation, comprising 100ml and/or 20ml each of a selection of our gold nanoparticles.

Product Name Code Type Applications
Gold Colloid IVD Sample Pack - 20mL GCIKITDIAG/4 Gold Colloid Lateral Flow Buy now
Gold Colloid IVD Sample Pack -100mL GCIKITDIAG/7 Gold Colloid Lateral Flow Buy now
Gold Colloid Life Science Sample Pack -100mL GCIKITLIFE/4 Gold Colloid Life Sciences Buy now

BBI Solutions gold nanoparticles for rapid diagnostic assays:

 

20nm Gold Nanoparticles 40nm Gold Nanoparticles 60nm Gold Nanoparticles 80nm Gold Nanoparticles
Average Diameter 19.0 – 21.0nm 37.0 – 43.0nm 57.0 – 63.0nm 77.0 – 85.0nm
Maximum acceptable % CV 8%
Number of odd shapes per 100 particles ≤5 ≤10 ≤10 ≤10
Optical density @520nm (using a 1 cm pathlength) Bulk available at OD1
Up to 50mL available at OD 5/10
Bulk available at OD1
Bulk available at OD 4.5 – 5.0
Up to 50mL available at OD10
Bulk available at OD1 Bulk available at OD1.0 at 555nm
Batch scale Up to 110L at OD1 Up to 340L at OD1 Up to 64L at OD1 Up to 64L at OD1
Capping agent Citrate
Presentation matrix Suspended in H2O, no preservative

Gold Nanoparticles

Size-matched colloid from 5 nm – 250 nm; ultra-uniform, ≥12-month stability and available in bulk ODs for seamless scale-up.

Control-line Conjugates

Reliable test validity using BSA, chicken IgY, mouse IgG or Protein A 40 nm conjugates - negative or positive controls on demand.

Gold Starter Packs

Unsure which diameter to pick? Evaluation kits supply four key sizes (5-40 nm or 20-80 nm) so you can optimise in a single order.

Tag Conjugates

Ready-made 40 nm labels against biotin, digoxin, FITC, His-tag or HRP—ideal for modular assay designs and multiplex formats.

Anti-human Conjugates

Goat or mouse antibodies to human IgG, IgM, IgA or IgE, adsorbed to 40 nm gold and delivered at OD 10.

Anti-species Conjugates

High-affinity goat antisera to mouse, rabbit or other species on 40 nm gold; build control or detection lines with confidence.

Fertility Conjugates

Monoclonal anti-hCG and anti-LH gold conjugates validated for rapid pregnancy and ovulation tests.

Gold Conjugates

Trusted Gold Conjugates from BBI

All of our conjugates are manufactured using our unique gold nanoparticles. We use our long-established proven processes to manufacture conjugates with outstanding performance and long-term stability. Our catalogue gold conjugates offer optimal performance, cost effectiveness and guaranteed quality, and are designed to help you develop and manufacture your assay rapidly and efficiently.

We manufacture all of our conjugates under our ISO13485 certification at our Crumlin headquarters.

BBI Solutions Gold Conjugates for Microscopy

Gold labels offer an effective method of labelling antigens for visualisation in the electron microscope.

BBI has a range of EM grade conjugates that combine different antibodies on a range of particles, predominantly from 5, 10 and 15nm. For researchers beginning to work with immunogold labelling, we recommend 10nm gold conjugates for observation, at a range of magnifications.

The main advantages of gold labelling lie in the high contrast and unequivocal nature of the label, the range of particle sizes suitable for different magnifications, the extreme sensitivity and the stability of the signal.

Please contact our Customer Services Team directly to discuss your requirements.

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IN FOCUS

ISO Certifications

All our gold colloid and conjugates are manufactured at facilities certified to internationally recognised ISO13485 quality management standards – so your diagnostics start with a proven quality backbone.

Our ISO27001 certification ensures your data is safeguarded, and we’re now charting a path to ISO 14001 and ISO 45001 to fold sustainability and safety into every batch.

Scientist smiling

ADDING VALUE

Performance

Backed by 70 years of reagent expertise, BBI products are engineered for consistent, assay-grade performance - batch after batch.

Scalability

From pilot-scale to full scale industrial runs, our bioprocesses and global logistics flex with your forecasts, ensuring on-spec supply worldwide.

Compliance

ISO 13485 certification plus FDA registration and full documentation make every lot audit-ready - speeding global approvals and market entry.

Security

Global primary manufacturing and secure supply chains ensure security of supply, so your production timeline stays protected.

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GET IN TOUCH

Still need help? Talk to our team

Our customer service team is on hand to help with any questions you have or support you need.

And if the issue is technical, they’ll bring in our world-leading expert scientists to troubleshoot side-by-side with you and keep your project moving.

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