Abstract

Micro-Analytical Devices for Therapeutic-Drug Quantification in Whole Blood at the Point of Care

Jean-Manuel Segura, Professor, Institute of Life Technologies, University of Applied Sciences and Arts Western Switzerland Valais

Therapeutic Drug Monitoring (TDM) allows for personalized dosage during therapeutic treatments and is often mandatory for modern potent drugs against cancer, infections or in organ transplantation cases. A prototypical example is the antibiotics tobramycin, which is often prescribed to neonates in case of bacterial infection and requires TDM to ensure efficacy while avoiding oto- and nephrotoxicity. Currently, the process of TDM is demanding for the patient as several milliliters of blood are required, is slow and costly due to the transfer of sample to a central laboratory, and suffers of limited efficacy owing to the difficulty to interpret the results for a non-specialist. In a first project, we aimed at circumventing these problems by developing a point-of-care device enabling the quantification of therapeutic drugs in blood using fluorescence-polarization immunoassays (FPIA). We showed that FPIA can be downsized with reduced requirements in blood sample (only 1 µL) and number of steps, without compromising assay reliability, and can be successfully integrated within paper-like micro-chambers. Whole-blood measurements were made possible by further using the paper-like micro-chambers as a filtering device. The final TDM point-of-care test requires minute amounts of blood and minimal handling steps. In a second project, we addressed cases where single measurements are not sufficient like during cancer chemotherapies. Here patients are subjects to administration of high doses of drugs during long periods of time which can last up to several days. Ideally, drug doses should be continuously adjusted to keep blood concentrations within the therapeutic range. This requires regular blood tests, typically every 15 to 30 minutes. I will present the latest results of a project aiming to develop an autonomous monitoring system able to continuously measure drug concentrations in blood.