What we do ?

We offer solutions for In Vitro Diagnostic applications

X4C technology enables the development of next-generation In Vitro Diagnostic assays. Calix[4]arenes, that covalently attach to any surface, form well-defined, exceptionally stable, very thin and homogeneous monolayers, ready for post-functionalization with any biomolecule.

  • X4C creates ultra-stable surfaces, resisting to low and high pH, etching conditions such as fluoride ions, high salt concentrations, high temperatures and drying, forming robust bioconjugates.
  • X4C technology controls the density of functional groups at the surface, enabling the control of the number of biomolecules at the surface, for more sensitive and cost-effective assays.
  • Calix[4]arenes coatings reduce the number of nanoparticles required for a test, cutting down the production costs of immunoassays.
  • X4C technology can be applied to control the orientation of biomolecules, for enhanced applications.
  • Calix[4]arenes can bind to any surface, of any shape and dimension, to produce any surface – biomolecule conjugate, opening the field of In Vitro Diagnostics to novel and innovative technologies.

Lateral flow

Ultra-stable and high-performance conjugates

While visually looking simple, lateral flow immunoassays, popularized by the recent COVID-19 pandemic, require the development and the production of multiple high technology components, including critical antibodies – label conjugates. For most of them, the label is a nanoparticle or a bead, made of gold or polystyrene (latex), of different sizes. The antibodies are typically attached to the particles through a passive adsorption process, leading to poorly controlled, randomly organized and oriented, and sometimes unstable conjugates. Covalent linking strategies exist, using polymeric structures bearing functionalities such as carboxylic or amine functions. Polymers are, by definition, large molecules that can affect the properties of the particles. Moreover, they exhibit size distributions profiles that are more or less controlled from batch to batch. The density and presentation of functionalities for the linking of antibodies are also very difficult to control.

X4C calix[4]arenes technology represents a new paradigm in the field, using small, well-defined organic molecules. They covalently form a perfectly controlled monolayer on surfaces, that is very thin and ultra-stable. By selecting the most appropriate calix[4]arenes, the functionalities and their density at the surface are easily controlled. Using calix[4]arenes technology generates high performance conjugates, which take In Vitro Diagnostics to the next level.


Enhanced Latex and Gold particles

Immunoturbidimetric assays are laboratory rapid, accurate and simple methods to determine the amount of an antigen in a sample by applying the principle of light-scattering measurements to antigen-antibody reaction. A specific category of immunoturbidimetry, called PETIA (Particle-Enhanced Turbidimetric ImmunoAssays), makes use of particles to increase the turbidity of the reaction, and so the signal and assay sensitivity. Plain particles or particle – antibody conjugates are used, depending on assay requirements.

X4C calix[4]arenes technology is perfectly adapted to modify latex and gold particles, providing the new materials with surface enhanced properties. Antibodies or other biomolecules can be immobilized covalently or passively to the newly modified particles, to generate highly performing conjugates.

Chemiluminescence immunoassays

Magnetic beads conjugation

Chemiluminescence immunoassays (CLIA) rely on paramagnetic particles or beads to perform separation and washing steps during the course of the assay. Nowadays, they represent the most common immunoassay method used in clinical central laboratories. Antibodies are typically covalently attached to paramagnetic particles made of iron oxide and polymers and/or silica. Different binding chemistries are available, but lot-to-lot consistency remains a concern for immunoassays developers and producers.

Calix[4]arenes are well defined small molecules that have the capacity to covalently bind any surfaces, including paramagnetic beads outer surfaces, creating functionalized particles in a perfectly controlled and reproducible process. Antibodies or any other biomolecules are then conjugated to the calix[4]arenes coated beads, leading to high performances conjugates.


Create your immunosurface

Biosensors are analytical devices that use the combination of a sensitive biological element, e.g. cell receptors, enzymes, antibodies, nucleic acids, etc., and a detector element, working through optical, piezoelectric, electrochemical or electrochemiluminescence signals. The variety of biological molecules and detector principles gives rise to a plethora of different devices, relying on multiple surface – biomolecule constructs.

The versatility of calix[4]arenes, which have the capacity to covalently bind to any surfaces, makes them very attractive for the development of such biosensors. Germanium, silicon or gold surfaces can easily be coated with calix[4]arenes, to host biomolecules, such as antibodies, peptides, oligonucleotides or proteins.

And more

Versatile technology

Thanks to their capacity to bind to any surfaces, calix[4]arenes are the partner of choice when looking for immobilizing biomolecules in Life Sciences applications. Microfluidic based lab-on-chips, Microarrays, ELISAs, Immunodots, Surface Plasmon Resonance (SPR) immunoassays, Fluorescence based assays, DNA/RNA extraction beads, and Electrochemiluminescence, are other applications in which the surface coating with a biomolecule is a critical factor of success.