A simple yet effective technology for non-invasive monitoring of health parameters for both clinical and non-clinical purposes.
Newly developed Sweat sensors can abolish the need of conducting blood tests soon. Currently, blood tests are indispensable for detection and monitoring of the presence/absence of pathogenic organisms and concentration of various hormones, cells and other biochemical compounds. Apart from clinical applications, blood tests are also used to check for presence of steroids or drugs in dope tests, monitoring alcohol consumption etc.
Recently, scientists came up with the idea of developing an all in one sweat sensor, which can help in analysing the general health factors and specific clinically important parameters.
Sweat sensing for a health snapshot
Sweat is a body fluid which contains biomolecules excreted form the body, which includes simple ions and complicated protein fragments. It also contains ethanol metabolites and drug residues in case the person had done alcohol or drug abuse.
Design and Features
The sweat sensors are so designed that they can be directly pasted onto the skin just like a tattoo and analyse the various health biomarkers of the body. A typical sweat sensor has the following components.
The type of biosensor to be integrated in the device depends on the need and requirement of the analysis. For instance, glucose biosensors are used to monitor diabetic patients, while lactate biosensors are used to monitor hyperlactatemia patients. Other types of biosensors may be equipped to analyse particular ions or metabolites.
The biofuel cell of the device powers the activity of the sweat sensors. Mostly glucose powered biofuel cells are used for this purpose, because they can run on the blood glucose and does not require replacement or maintenance.
The electrodes used in the device varies on the type of biosensor integrated in the device.
The Sensor patch which is usually integrate the electrode designs assembled along with the biocompatible and skin friendly generic athletic tape, which remains covered with medical gauze to ensure flexibility and efficient sweat collection for analysis.
The collected sweat enters the microfluidic system which functions as the inputchannel for the embedded biosensors. The data generated from the analysis can be sent to remotely connected wireless devices for further analysis or record maintenance, as may be the case.
Monitoring alcohol consumption lifestyle
Sweat sensors made up of two co-planar sensors of gold and zinc oxides can detect the presence of ethyl glucuronide (EtG), a metabolite of ethanol. Additionally, the device can be supplemented with LED bulbs which can directly signal the presence of metabolites of ethanol in the sweat.
The biosensor can help in tracking and monitoring the patients undergoing rehabilitation or treatment for addiction to alcohol consumption.
Lactate detection and monitoring
It is a well-known fact that the levels of lactate in body fluids increases when the body starts metabolizing body fats, which occurs either when doing extensive physical activities, starvation or when the patient is suffering with chronic illnesses.
The sweat sensors can be used to monitor the lactate levels to track body fatigue of patients suffering with hyperlactatemia. In some cases it may indirectly indicate improper functioning of glucose and fat metabolism pathways. The currently developed sweat sensors make use of biosensors which function on the principle of the enzymatic reaction of lactate dehydrogenase.
What is its future?
The sweat sensor technology has just started gaining popularity and are preferred by medical professional and athletes due to their easy access and uncomplicated modus operandi. Scientists are further engagedin improving the technology to provide better results. It is highly likely that sweat sensors may replace blood tests as the basic clinical method of health assessment.