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In-situ optical bio-sensing probe

A novel bio-sensing platform for the detection of large macromolecules such as proteins being able to operate either in-vivo or in-vitro for medical diagnostic applications or as a research instrument.

BenefitsIn-situ Optical Bio-sensing Probe

  • Robust and biocompatible optical detection system
  • Remote detection through the use of optical fibres
  • Non-disruptive technology allowing detection in-vivo or in-vitro
  • Versatile sensing platform
  • Multiplexed sensing capability and ability to perform detection of specific biomolecules in complex biological samples such as undiluted serum.


This technology is uniquely positioned as a label free sensing platform exhibiting similar capabilities (real time kinetic measurement, quantification and determination of binding constants) compared to more well-known and commercially viable technologies such as Surface Plasmon Resonance as measurements can be performed either in-vitro or in-vivo. 

This platform technology is capable of detecting proteins, viruses, bacteria for a large range of applications depending on the surface functionalization (antibodies) in various clinical samples, including undiluted serum without non-specific binding which often results in false positive results.


This unique label free bio-sensing platform technology relies on combining the refractive index sensing capability of Whispering Gallery Modes in dye doped spherical micro resonators with the unique light guiding properties of micro structured optical fibres.

The fibre provides a pathway for remotely existing and collection of the Whispering Gallery Modes signal produced by single or multiple microspheres simultaneously, positioned onto one end of the fibre. The specific architecture of the fibre also enables the microsphere to be held in position, anchoring it into one of the fibre holes, running along the entire fibre length. More importantly, this permits easily manipulation and positioning of the microsphere where sensing needs to be done.

The sensing mechanism is based on exploiting the sensitivity of Whispering Gallery Modes toward changes of refractive index at the surface of the dye doped microsphere. Appropriate surface functionalization of the microsphere surface ensures that only the desired target analyte can bind to the microsphere surface, which in turn produces a wavelength shift of the resonance features proportional to the amount of bound analyte, enabling not only detection but also quantification.

The approach of using dye doped microspheres allows exploiting lasing of the Whispering Gallery Modes which improves the resolution of the sensing platform and enables better performances. The use of multiple microspheres with different surface chemistry enables either to compensate for change of local environment, including non-specific binding in real clinical samples, or to detect multiple analyte simultaneously.

Potential Markets

  • Manufacturers of medical devices
  • Point of care applications
  • Research instruments
  • Biomedical diagnostics
  • Bio-sensing platforms
  • Food packaging.

IP Status

A patent application has been filed in various national territories.

Partnering Opportunities

We are seeking development partners and technology licences in the area of bio-sensing technologies for medical diagnostics applications or as a research instrument.

Commercial enquiries: