Scientists in Canada have used small molecule probes anchored to nanoparticles to label and detect biomolecules. 

Labelling tumour cells or other biomarkers with nanoparticles generally relies upon modifying the surface of the nanoparticle with antibodies. However, this can pose problems because the antibodies can adopt many different orientations due to their numerous functional groups that are compatible with the surface chemistry used to anchor them to the nanoparticle surface. 

Arnold Kell and Benoit Simard from the National Research Council of Canada have overcome this problem by developing small molecular probes that can be attached to the surface of the nanoparticle with a defined orientation and controlled architecture. By utilizing these molecules, they have been able to investigate the effects of small changes to the orientation of a molecule on its ability to interact with large complex molecules. 

Small molecule probes such as this are well known to have long term stability. Therefore, the team believe that their new probe will offer advantages in point-of-care diagnostic devices where antibodies and other biomolecules are not able to bind together efficiently. 

'The development of diagnostic devices based on functionalized nanoparticles depends greatly on the level of sensitivity that can be achieved with these unique materials,' said Simard. The team now face the next challenge of implementing their system into complex solutions such as blood and other biological fluids. 

Jenna Wilson