using-human-sweat-as-diagnostic-tool-and-source-of-power

Context:The role of sweat fluid in our body and the chemicals it contains are becoming increasingly understood and utilised.

More on news: 

  • Need no pills or potion: Skin specialists do an interesting procedure, in which they attach a thin polymer-based sheet which contains the desired drug, stick it to the skin on your arm or chest and deliver the drug past the sweat fluid directly into the body, using a tiny electric current on the patch.

 

About E-Skin

  • Electronic skin refers to flexible, stretchable and self-healing electronics that are able to mimic functionalities of human or animal skin.
  • The broad class of materials often contain sensing abilities that are intended to reproduce the capabilities of human skin to respond to environmental factors such as changes in heat and pressure.
  • With the advent of microelectronics and biocompatible polymers, we now have ‘electronic skin’ (e-skin), and nanoscale wires that can be attached and an external electric power supply using micro-scale batteries.

 

Role of sweat: 

  • Sweat comes out of three types of glands distributed across all over our skin, secreting water and substances that help keep our body at the optimum temperature of 37 degrees C (or 98.4 degrees F). 
    • Humans have three different types of sweat glands: eccrine, apocrine, and apoeccrine.
  • Our brain has temperature-sensitive nerve cells (neurons) which control the sweat glands in releasing the fluid depending on the temperature and physical and metabolic activity of the body. Sweat is thus our body’s thermo-regulator.
  • Composition of sweat: 99% water containing sodium, potassium, calcium, magnesium and chloride ions, ammonium ions, urea, lactic acid, glucose and other minor components.
  • Significance:  
    • An analysis of the sweat fluid in a patient and how it compares with that of a ‘normal’ individual will thus be of diagnostic value (just as much as other body fluids do).
    • E-skin patches can be used for real-time measurements of some chosen component in the sweat, using the appropriate probe (sensor) in the patch in order to detect and measure the level of the component. 
  • Sweat as power supply: On a patch on the individual’s e-skin patch enzyme Lox can be added which would react with the lactate in the sweat and oxidise it to pyruvate in a bioanode, and reduce the oxygen into water in a biocathode, thus generating electrical energy that is sufficient to drive the patch with no external energy source.

Source: https://www.thehindu.com/sci-tech/science/using-human-sweat-as-diagnostic-tool-and-source-of-power/article31489392.ece

Image Source: the hindu