Gold Colloid, Co. – Pioneering Rapid Test Production & Assay Development Solutions

Innovating Diagnostics for a Healthier Tomorrow 

About Gold Colloid Co.

We started with a simple conviction: that the particles powering the world's rapid diagnostic tests deserved more precision, more consistency, and more scientific rigor than the market was offering.

Gold Colloid Co. is a San Diego-based nanotechnology and diagnostics company specializing in gold nanoparticles and lateral flow assay development. We supply the core materials and scientific expertise that enable researchers, biotech companies, and diagnostics manufacturers to bring fast, reliable tests to market — from a first proof of concept to a commercial product on the shelf.

What we do

Our work spans two closely linked disciplines. On the materials side, we produce high-purity gold colloids across a range of particle sizes, formulated for conjugation and optimized for the performance demands of lateral flow applications. On the development side, our scientists take on the full complexity of assay design — antibody selection, particle conjugation, nitrocellulose optimization, validation, and scale-up — so our partners don't have to build that expertise from scratch.

We've guided projects from a handwritten hypothesis to a finished diagnostic product, across healthcare, food safety, environmental monitoring, and beyond.

Who we work with

Our partners range from academic researchers exploring a new target to established diagnostics companies expanding their product lines. What they share is a need for a technically credible partner who can move fast, work precisely, and deliver results that hold up under real-world conditions.

Where we're going

Rapid diagnostics are becoming more important, not less. The demand for point-of-care tests that are fast, accurate, and manufacturable at scale is growing across every sector we serve. We're building the materials science and assay development infrastructure to meet that demand — one well-made particle at a time.