Bio Layer Interferometry Probe (BLIP) for in-vivo analyte detection

Unmet Need

Diagnostic tests play a critical role in the clinical diagnosis, management, and monitoring of disease. These tests are designed to analyze biological specimens to identify analytes of interest by employing highly specific and sensitive analyte-ligand binding pairs. Currently, most diagnostic tests use a centralized-testing model, where samples are collected, processed, and analyzed using laboratory-based methods. However, these methods are time consuming, costly, and not intended for sensitive point-of-care detection of analytes, especially in difficult to access organs or in fluids of low overall volume or concentrations. There is an urgent unmet clinical need for new analytical methods capable of fast, in vivo analyte detection at the bedside to overcome the limitations of existing laboratory-based methods.


Duke inventors have developed an analytical system and probe to detect a variety of analytes in vivo. This is intended for clinical applications where monitoring analytes in vivo could be beneficial. For example, the probe can be inserted into the eye to measure therapeutic drug concentrations or disease biomarkers directly from native tear, aqueous, vitreous, or suprachoroidal fluid. Specifically, the apparatus is composed of a bio layer interferometry probe (BLIP) functionalized with a ligand on the fiberoptic tip. The BLIP platform is modular, as the ligand can be changed depending on the analyte of interest. In the presence of the analyte, a shift in the interference pattern occurs which can be measured in real-time, thus enabling precise measurement of analyte concentration directly from in vivo bodily fluids that are hard to access using other methods. This system has been demonstrated using the ForteBio Octet platform to detect proteins, including SARS-CoV-2 antibodies, in saliva.


  • Quick and sensitive label-free detection of analytes in small spaces in vivo
  • Especially useful for measuring clinically informative biomarkers directly from hard to access bodily locations, such as fluid in the eye, cerebrospinal fluid, or synovial fluid
  • Modular platform that can be adapted to measure a wide variety of analytes
  • Can be multiplexed to detect several analytes simultaneously
  • Bypasses the need for a centralized testing model, allowing for point-of-care testing in an easy-to-use form factor
A close-up of the female eye (Source: Envato)

Duke File (IDF) Number



  • Barnett, Bradley
  • Denny, Thomas
  • Fekrat, Sharon

For more information please contact


School of Medicine (SOM)