UofM Researcher Helps to Develop Innovative Drug Detection Technology

Receives patent for electrochemical sensor technology for measuring drug concentrations

Sept. 28, 2022 — The United States Patent Office awarded Dr. Ernő Lindner and Vanderbilt University professor Dr. Edward Chaum with the patent: “Method and device for detection of bioavailable drug concentration in a fluid sample” (U.S. Patent 11,375,929 B2).

Lindner is the R. Eugene Smith Professor of Biomedical Engineering and professor of Chemistry at the UofM. Chaum is a professor of Ophthalmology & Visual Sciences; Biomedical Engineering; and Pathology, Microbiology and Immunology at the Vanderbilt Eye Institute.

This patent is the result of more than 10 years of collaborative research between Lindner and Chaum. Originally, with support from U.S. Army Medical Research and Development Command, they worked on the development of an electrochemical sensor for target-controlled infusion of the anesthetic drug Propofol.

“This recently issued patent is a great example of a much-needed collaboration between clinicians and biomedical engineers in order to advance biomedical technologies,” said UofM President Dr. Bill Hardgrave. “I look forward to seeing the commercialization of this licensed technology that will help physicians improve patient care and clinical outcomes in the near future.”

Throughout the years, their propofol sensor was developed into a sensing platform for therapeutic drug monitoring and led to the foundation of the start-up company Infusense. Based on the documented results with the sensing platform prototype and the promise of real time continuous monitoring of various drugs in whole blood in 2021, Infusense was awarded an SBIR Phase I grant from the National Science Foundation entitled “Point of Care Electrochemical Platform for the Rapid Detection of Drug Toxicity.”

The focus of the NSF supported work at Infusense is the development of methods and prototype devices for the utilization of the unique sensing platform for the assessment and determination of potential toxicity of antidepressant, anti-psychotic and immunosuppressant drugs in emergency situations as well as during treatment through continuous monitoring.

The therapeutic blood concentration ranges of these molecules, e.g., the tricyclic antidepressant drug Amitriptyline and its metabolite Nortriptyline, is below 1.0 mM/L, which must be measured in the presence of 1000 times more concentrated interfering compounds like ascorbic acid and Tylenol. This could be achieved with the patented, modification of a conventional electrochemical sensor that enhances the analytical signal with simultaneous reduction of the signal of hydrophilic interfering compounds.

As a consequence, the multilayer structure of the modified sensor offers exceptional limit of detection with superb selectivity. Both are critically important for reliable assessment of drugs with therapeutic concentrations in the micro- and nano-molar concentration range (e.g., 80 pmol/L for CBD or 5.0 nmol/L for Fentanyl).

The sensing platform is envisioned as a low cost, single use device for on-the-spot drug testing or emergency room toxicity assessment (e.g., Fentanyl and CBD) and as the detector cell in complex flow-analytical systems during continuous, feedback-controlled monitoring of tricyclic antidepressants and selective serotonin reuptake inhibitors such as Amitriptyline and Sertraline, respectively. Both areas of utilization are expected to improve patient safety and reduce cost while providing better outcomes.

For more information on this patent and/or the technology, contact Lindner at elindner@memphis.edu.