Researchers Águeda Molinero, Qianyu Wang, Xing Xuan, Asa Konradsson-Geuken, Gaston Crespo and María Cuartero, from the UCAM Chemical Sensors Unit (UCAM-SENS), together with researchers from the Swedish universities, KTH The Royal Institute of Technology and Uppsala University have developed a sensor capable of measuring CO2 in the interstitial fluid of the skin, without the need to access blood samples. This milestone, published in the industry's leading scientific journal, ACS Sensors marks a turning point in the monitoring of this gas in the human body. 

The sensor is able to measure CO2 in the interstitial fluid of the skin, without the need for access to blood samples

The innovation represented by this electrochemical microneedle system could revolutionise patient care in intensive care units (ICUs). Currently, obtaining arterial blood samples to analyse CO2 levels involves invasive and painful procedures, such as inserting catheters into arteries. Thanks to this new sensor developed by UCAM-SENS, it will now be possible to obtain accurate CO2 concentration data in real time with a tiny needle system without causing discomfort in the patient.

It could revolutionise patient care in intensive care units (ICUs)

This pioneering process makes it possible to measure CO2 in interstitial fluid thanks to two main factors. ‘Firstly, because of the similarity in composition between blood and interstitial fluid. Secondly, thanks to a new detection strategy that combines the analysis of two ions (electrically charged particles) simultaneously to calculate, through a series of simple equations, the concentration of CO2 gas in interstitial fluid and relate it to the content in blood,’ says Águeda Molinero, a researcher at the UCAM-SENS unit.

Utilities

Apart from allowing the non-invasive measurement of CO2 concentration in the blood of patients to aid diagnosis, this sensor can be used in any activity where CO2 in a liquid sample needs to be measured. María Cuartero principal investigator and head of UCAM-SENS, underlines the potential of this research in other sectors such as ‘agriculture, to monitor the photosynthesis cycles of plants, or the environment, to detect and predict water acidification processes’.

This technology, which will soon begin its clinical trial phase, can be combined with other microneedle sensors developed by UCAM-SENS capable of measuring the patient's pH, sodium, potassium, calcium, lithium and chloride levels, with the aim of making future patient diagnoses more agile and less invasive. 

To this end, UCAM-SENS has a multidisciplinary work team ranging from the design of the electronics to the chemistry of the sensor, with the aim of taking this innovation from the laboratory to the real world, since, as Estrella Núñez, UCAM vice-rector of Research, stated ‘one of the main commitments of scientists is to develop research projects whose results reach society. It is part of our social responsibility.’