Nano Flow offers a service of custom bioconjugation to its highly spherical 20 and 40nm citrate-stabilized gold nanoparticles. The resulting gold conjugates offer high sensitivity, precision and high stability, helping our customers to build high-performing lateral flow immunoassays. Our innovative industrial process of antibody (protein or DNA) conjugation ensures a very smooth conjugation step limiting gold aggregation and allowing to reach excellent batch-to-batch reproducibility.

When you do not have time or resources to develop your own gold conjugate, or when you need to increase your production scales and you are not equipped for, choosing Nano Flow custom gold conjugates is your best option

At Nano Flow, we closely accompany our customers and their products toward high-scale manufacturing. For this perspective, we respect a 4 step-process:

  1. Definition of the product’s technical specifications and list of Quality Control tests with expected performance criteria.
  2. Feasibility study including optimization of the passive adsorption conjugation conditions using e.g. antibody quantities as low as 1mg. This integrates identification of best conjugation pH, blocking agent and screening of different antibody concentrations.
  3. Production scale validation with three QC compliant production batches.
  4. Gold conjugate production and QC release following expected performance criteria.

Our custom conjugation service also includes support in the selection and sourcing of antibodies, selection of the best nanoparticle size for your specific application, and assistance in the storage buffer optimization and post-delivery technical assistance.

Why partner with Nano Flow for your gold conjugates?

Lot-to-Lot reproducibility

With our state-of-the-art equipment including automated production units with in-line controls of process critical parameters and automated purification units, we offer the best controls on our conjugation process. This limits the risk of human mistakes and allows to identify any possible drift of the process earlier in the manufacturing of our products. QC release based on agreed performance criteria also helps to avoid non-compliant antibody-gold conjugates.

High sensitivity

With our smooth conjugation process, the gold nanoparticles instantaneously get into contact with the antibody to be conjugated. Each gold nanoparticle is stabilized with the same quantity of antibody. Consequently, our highly spherical gold colloids do not bind to antibodies already bound to other particles lowering aggregation. By limiting aggregation, Nano Flow gold conjugates expose more active antibodies for improved sensitivities.

Improved stability

The high sphericity of the gold particles and our unique conjugation process prevent gold particles and conjugates from aggregation. Therefore, Nano Flow gold conjugates offer several years stability when stored in proper conditions.

High flexibility

Nano Flow remains flexible about the product features supplied to its customers. This includes the final concentration of gold conjugates (OD 1-100), the production scale (100ml-100L+), the antibody concentration to be conjugated to gold nanospheres, the blocking strategy and the storage buffer. We are always opened to discussion and ready to adapt our strategy to satisfy our customers.

Product Features

40nm Custom Gold conjugate 20nm Custom Gold conjugate
Size 40+/-3 nm 20+/-3nm
CV on particle sizes <13% <15%
Sphericity 99+% 99+%
Odd shapes per 100 particles ≤1 ≤1
Optical Density From 1 to 100 From 1 to 100
Antibody load From very low to saturation From very low to saturation
Suspension Borate buffer or conjugate pad compatible Borate buffer or conjugate pad compatible
Single batch scale Max. 20L (OD10) Max. 20L (OD10)

All our gold conjugates are supplied with a Certificate of Analysis to guarantee products meet specifications. This certificate includes Transmission Electron Microscopy, Dynamic Light Scattering and UV-vis spectroscopy information. Other characterizations may be available on demand.