Ammonium is a biomarker used to diagnose a range of rare inherited metabolic disorders. For example, primary disturbances of the urea cycle, various organic acidemias, and other metabolic and environmental conditions that affect liver function. urea cycle. Ammonium is also useful in researching and monitoring various liver disorders (diseases that affect the normal functioning of the liver) caused by the consumption of alcohol and other drugs, pharmaceuticals, and other environmental factors.
All of these disorders produce excess ammonium, which endangers the patient’s health. Considered a serious case, values above 500 micromoles per liter can cause irreversible damage to the brain and can even lead to death. Therefore, early diagnosis in real time is critical to minimize the effects of hyperammonemia episodes on neurological function. Currently, patients diagnosed with disorders that include hyperammonemic episodes require regular hospital visits and blood samples taken for laboratory treatment and analysis.
Researchers from the UAB’s Chemistry Division’s Sensors and Biosensors (GSB) Research Group collaborated with Sant Joan de Deu Hospital and UPC to develop a point-of-care (POC) analyzer to monitor chemical levels . Instead of sending blood samples for analysis in hospital laboratories where traditional equipment is used, point-of-care and decentralized methods are used to remove ammonium from the patient’s blood. This new device aims to decentralize blood ammonium measurement, measuring blood directly and enabling analysis in smaller medical centers without the need for previous treatment. This means increasing the number of monitoring sites, simplifying processes and reducing the time required to make medical decisions.
It is very important to increase the frequency of blood analysis to determine ammonium levels.”
Mar Puyol, Research Director, UAB Researcher
She continues: The sooner a doctor can act, the better, and that can be achieved using point-of-care analyzers like ours. “
Verification in hospital
The research team is preparing a prototype that works under semi-autonomous conditions. Once the instrument is ready, all ammonium samples analyzed daily at Sant Joan de Deu Hospital will be measured using conventional methods and new instruments created by the researchers. Nonetheless, Puyol said, “By the time the final prototype of the point-of-care analyzer is validated, hundreds of samples will be needed. The next step is to industrialize the device and bring it to market. There are still steps to be taken to get there, and even in that scenario, the device is expected to become an economical alternative to facilitate liver disease monitoring in developing countries. .”
The device uses a microfluidic platform containing a potentiometric detection system and gas separation membranes. In this way, it is possible to automatically separate ammonium in the form of ammonia from the rest of the complex matrix of blood, obtaining selective detection without other types of interference. This ensures accurate and accurate determination of ammonium concentration in whole blood but not in plasma. This is the traditional method used to analyze this parameter.
Led by researchers Julián Alonso-Chamarro and Mar Puyol Bosch of the Sensors and Biosensors Research Group at UAB’s Chemistry Division, the study is the result of a proof-of-concept R&D&I project (PDC2021-121558-I00) that was conducted. It is the result of a collaboration with researcher Rafael Artuch of Sant Joan de Deu Hospital (HSJD) and his Javier Rosell of UPC’s Center for Biomedical Engineering Research (CREB). This research includes the support and involvement of Fundación PKU-OTM (phenylketonuria and other inherited metabolic disorders). Validation of the system is being carried out at the Sant Joan de Deu Hospital in Barcelona.