tailored gold bioconjugates

We partner with the most innovative diagnostic companies in the world. Utilizing our patented surface chemistry, K-One®, we develop, manufacture, and supply advanced gold bioconjugates, specifically tailored to your biomolecules and applications. Our bioconjugates enhance your assay performance, offering up to a 10x improvement in Limit of Detection (LoD), while also drastically reducing the number of false results, and ensuring a high level of reproducibility even for the most complex samples.

Scheduling a 30-minute call with our scientific team is the best way to assess how Kimialys can help.

A person holding a Lateral Flow Assay in his hand
Lateral Flow Assays

While Lateral Flow Assays (LFAs) play a crucial role in diagnostics, they often face challenges due to suboptimal nanoparticle bioconjugation, leading to diminished sensitivity and undesirable membrane interactions. Achieving a low Limit of Detection (LoD) and maintaining clear strips are always important, but these aspects become even more critical in tests that require the detection of very low antigen concentrations or necessitate rapid and precise results in emergency point-of-care settings.

We develop, manufacture, and supply advanced gold bioconjugates, ensuring optimal performance across a variety of complex samples, including blood, plasma, cell extract, saliva, urine, and milk.

As a test developer, you seek to refine a multitude of parameters that directly impact the effectiveness of your assays. This includes enhancing sensitivity for the accurate detection of low-concentration analytes, ensuring both specificity and selectivity to improve test reliability and reduce false positives, protecting surfaces from undesired interactions, and maintaining assay reproducibility to guarantee consistent results across different runs and conditions.

At Kimialys, we proficiently address all of these challenges through our unique antibody screening and bioconjugation methodology.

Learn more about the FirstTimeRight approach

Sandwich & competitive LFAs

Sandwich LFAs, also known as conventional LFAs, are the preferred choice for detecting large analytes. This method employs a dual-antibody approach, where one antibody serves to capture the target molecule while the other acts as a detector. To optimize the performance of your sandwich LFAs, we utilize our unique antibody selection platform using the technique of Surface Plasmon Rresonance imaging (SPRi) to screen and identify the most effective antibody pairs.

On the other hand, competitive assays excel in detecting small molecules since these molecules are often too small to simultaneously bind two antibodies as required in classic LFA sandwich method. This approach is particularly prevalent in drug testing and toxicology control (testosterone, fentanyl, benzodiazepines...). The success of competitive assays is more influenced by surface chemistry due to their reliance on a singular binding event, where every interaction counts. Our proprietary K-One® technology underscores this criticality, offering an optimal platform for competitive assays that prioritize sensitivity and specificity.

Lateral Flow Assays applications:

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Troponins, BNP, CRP/hs-CRP

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Infectious diseases (1/2)

SARS-CoV-2 (spike, nucleocapsid), HIV (p24, gp41, gp120), influenza virus (nucleoprotein, hemagglutinin, neuraminidase), dengue fever (NS1, envelope protein, IgM/IgG)

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Infectious diseases (2/2)

HBV (HBsAg, HBeAg), malaria (PfHRP2, pLDH, aldolase), streptococcus A (streptolysin O, DNase B), tuberculosis (IGRA), C. difficile infection (C. difficile toxin)

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Breast (HER2/neu, ER, PR), prostate (PSA), colorectal (CEA), lung cancer (EGFR mutations)

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Hematologic malignancies (BCR-ABL, CD20), anemia (EPO, ferritin, transferrin), blood clotting disorders (factor VIII, factor IX, prothrombin, VWF, D-dimer)

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Autoimmune disorders/rheumatology

Rheumatoid arthritis (anti-CCP, RF), systemic lupus erythematosus (anti-dsDNA, ANA), celiac disease (tTG-IgA, EMA), spondyloarthropathies (HLA-B27)

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Diabetes (insulin, C-peptide, glucose, HbA1c), thyroid disorders (TSH, free thyroxine)

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Other diagnostic areas

  • • Neurology: Alzheimer's disease (Amyloid-β, Tau)
    • Respiratory: asthma and COPD (FeNO)
    • Nephrology: chronic kidney disease (NGAL)
    • Gastroenterology: helicobacter pylori (urease)

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Toxicology - bioterrorism agents

Anthrax toxins, botulinum toxin, ricin, staphylococcal enterotoxins

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Toxicology - drugs and doping (competitive LFA)

THC, cocaine metabolites, methamphetamine, opioids, testosterone, fentanyl, benzodiazepines

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Other applications (sandwich LFA)

Food (peanut allergens, gluten, salmonella, E. coli), environnemental safety (heavy metals, pesticides, herbicides), veterinary (pregnancy-related hormones)

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Other applications (competitive LFA)

Pregnancy tests (hCG), hepatitis C (HCV core)

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Other nanoparticle-based bioassays

On top of Lateral Flow Assays, we leverage our proprietary K-One® technology and implement the FirstTimeRight (FTR) approach in every nanoparticle-based bioassays we undertake.

Nanoparticule-based Immuno-PCR (iPCR)

Traditionally, PCR and RT-PCR techniques are limited to targeting nucleic acids (DNA/RNA). Immuno-PCR expands these capabilities by combining the principle of immunoassays, which can target a broad range of biomolecules, e.g., proteins and antibodies, with the sensitivity and amplification power of PCR.
This approach achieves ultra-sensitive detection levels, often in the femtogram range, surpassing conventional methods and making it ideal for identifying low-abundance biomarkers in scenarios such as early disease detection and tracing minute contaminants.


LAMP-LFA integrates the speedy DNA/RNA amplification of LAMP with the direct visual interpretation of Lateral Flow Assays, providing an efficient hands-on diagnostic solution, without the need for costly amplification and reading equipment. Our innovative approach, backed by gold nanoparticles and pioneering biologics, bridges the reliability of PCR with the affordability of LFA, positioning it as a versatile tool for rapid disease detection, from Covid-19 to a range of other pathogens.

We are currently leading an innovative project in molecular diagnostics.

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Antibody depletion - ADA

Nanoparticle-based antibody depletion is a widely used techique to purify samples. At Kimialys, we leverage this technique to highlight the immune system's production of Anti-Drug Antibodies (ADAs) in response to certain immunotherapies, which can compromise treatment efficacy. Our cutting-edge method, made possible by Kimialys' proprietary gold nanoparticle coating, advances the drug tolerance of standard assays (such as ELISA, MSD...), setting a new standard for early ADA detection and enabling more precise therapeutic decisions in medical fields such as rheumatology and oncology.

We are currently leading an innovative project in immunogenicity testing.

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Signal amplification for IVD tools

Nanoparticles can significantly enhance detectable signals in In Vitro Diagnostic (IVD) tools, even for low-abundance targets. Our innovative approach to nanoparticle-based signal amplification ensures specific and robust signal enhancement, thereby elevating the sensitivity and accuracy of IVD assays. This enhanced detection capability is crucial for early diagnosis and monitoring very low variations in biomarkers, making it indispensable for challenging clinical diagnostics.

Other materials than gold

While our core focus at Kimialys is on gold-based biosensing applications, we are also open to transferring our technology to other materials (magnetite, latex, fluorescent materials, lanthanides, carbon, cellulose...). Our projects involving these alternative materials are demonstrating promising results, reinforcing the versatility and reach of our technology.

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It is highly-

It is highly-recommended

to work with us!

It is highly-sensitive

Achieve up to a 10x improvement in the limit of detection (LoD) compared to standard methods.

It is highly-specific

Minimize false results and ensure clear test strips without background interference.

It is highly-reproducible

Expect consistent and reliable results across complex samples such as blood, plasma, cell extract, saliva, urine, or milk.

It is highly-functional

More than 90% of immobilized ligands are functional and can interact with their target.

It is highly-tailored

We provide tailored solutions only, specifically designed for your biomolecules and assays.

It is highly-innovative

Benefit from our expertise in SPRi technology and patented K-One® surface chemistry for superior diagnostics.

It is highly-efficient

Our antibody screening process is 5x faster on average than conventional methods, ensuring quick turnarounds.

It is highly-actionable

With detailed reports and comprehensive presentations, we provide actionable insights and a thorough understanding of the results.

It is highly-trusted

Supported by reputable academic institutions and backed by both public and private funds, we constantly push further the boundaries to enable the development of the diagnostic tests of tomorrow. Our clients' high satisfaction stands testament to our reliability and proficiency.

Kimialys FirstTimeRight approach

We do not offer off-the-shelf bioconjugates, because each project is unique.

In bioconjugate-based assays, including Lateral Flow Assays, the prevailing practice involves empirically screening and optimizing multiple off-the-shelf solutions, aiming to identify the most suitable bioconjugates for efficient and specific antigen capture. However, such an approach often demands significant time and resources, with no guarantee that the selected solutions will meet the desired performance requirements.

This challenge arises because every biomolecule has unique and intricate characteristics, such as size, hydrodynamic volume, isoelectric point, surface, total charges, among others. Concurrently, each assay is influenced by distinct parameters which include its format (sandwich/competitive, etc.), the biological matrix (buffer, serum, cell extract, urine, milk, etc.), and the purpose of the assay (quantitative/semi-quantitative/qualitative), among others.

With this understanding, we consciously chose not to offer off-the-shelf products. Instead, we present the Kimialys FirstTimeRight (FTR) approach: a time-saving methodology for screening & bioconjugation tailored to each of your biomolecules and assays, ensuring optimal performance from the start, eliminating the need for repeated iterations and optimizations.

Step 1 - The screening

Antibody (or any other ligands) screening by SPRi

Our expertise is not limited to nanoparticles, as we also possess unmatched skills in Surface Plasmon Resonance imaging (SPRi). With SPRi, we rapidly identify optimal antibodies and antibody pairs for a range of bioassays, encompassing lateral flow assays and other nanoparticle-based biosensing techniques. This is a unique and groundbreaking advancement in the development of diagnostic assays.

Traditionally, test developers undergo a labor-intensive procedure when screening multiple antibodies. This process includes preparing bioconjugates, arranging membranes, conducting numerous test combinations, refining reagent concentrations, and recalibrating instruments... The required time even intensifies when pinpointing the best antibody pairing for sandwich LFAs due to the high number of combinations. By leveraging the multiplexing capacity of SPRi, combined with our patented surface chemistry, K-One®, we drastically streamline this screening process, making our approach 5x faster on average than conventional methods.

To take things even a step further, the multiplexing capabilities of SPRi extend beyond antibody selection, as it can also be used for optimizing the immobilization conditions for each antibody screened, thereby maximizing its potential. This additional optimization, if attempted using traditional LFA methods, require a very large number of test combinations, underscoring the substantial time savings our method offers.

Step 2 - The bioconjugation

K-One® powered gold bioconjugates

It goes without saying that all insights gained through SPRi can be directly applied to gold nanoparticles, without the need to reoptimize the surface chemistry.

Unlike the conventional passive adsorption method, we begin by pre-functionalizing the surface of the gold nanoparticles with K-One® chemistry, facilitating the covalent attachment of antibodies during bioconjugation. This method ensures optimal control over the antibodies' exposure, orientation, distribution, and density on the nanoparticle surface. As a result, we maintain over 90% of ligand functionality, a substantial improvement compared to less than 30% typically achieved with traditional approaches.

By synthesizing our own gold nanoparticles in-house, we maintain high quality and control over the production process. This ensures that our nanoparticles consistently meet our rigorous standards for performance and reliability.

FirstTimeRight approach in summary

Step 1: during this selection phase, we optimize our surface chemistry to suit your specific ligands, determine the optimal conditions for immobilization, and ultimately select the best-performing antibodies tailored for your assay, by SPRi.

Step 2: during the bioconjugation phase, we pre-functionalize the nanoparticles with our K-One® surface chemistry and apply the insights gained in step 1. This approach streamlines the process, as there is no need to reselect the optimal ligands to use for the bioconjugation nor reoptimize the surface chemistry. In the end, 90% of the ligands are functionalized, their binding sites being readily available for antigen

Performance: while the FirstTimeRight (FTR) approach undeniably saves time, our primary focus is on the enhanced performance it brings to your assay. This method significantly improves the limit of detection (LoD), increasing sensitivity by up to 10x compared to standard procedures. Additionally, it drastically reduces the number of non-specific interactions: this is achieved by selecting the most specific and selective antibodies, thereby minimizing the risk of false results, and by protecting the surface with our K-One® chemistry to prevent undesired interactions. In fine, our approach ensures the detection of very low concentrations of analytes and provides clear visual and analytical readouts on strips, guaranteeing highly reproducible assays with consistent, reliable and repeatable results, even for the most complex samples such as blood, plasma, cell extract, saliva, urine, and milk.

Their biomolecules are in the right hands:

Reach out to us!

Curious about how our expertise in Lateral Flow Assays and other nanoparticle-based assays can help you meet your target performance?

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