From the beginning of COVID-19 we have focused on SMS [ sanitizer, mask ,social distancing ]. Along with that we have added some new elements in our everyday life including IR thermometer ,pulse oximeter etc. So what we know about oximetry that it measures level of oxygen in our blood as well as pulse rate . But now some videos surfing on social media claiming that they could measure oxygen level of biscuits too. So you would ask whether it is real or not Then I am going to explain it
At first let us know how oximeters work .
Oxygen is carried in blood by using HAEMOGLOBIN [Hb] that is present on RBC .When Hb binds with oxygen called oxyhemoglobin and blood as oxygenated and blood containing Hb without oxygen as deoxygenated.
Images below would clear your doubt
Half of Hb are combined with oxygen so oxygen level is 50
¾ of Hb are combined with oxygen, so it is 75
All of Hb are combined so oxygen level is 100
NOW , consider a pulse oximeter it has two light source, those are Red light (600-750 nm wavelength) and Infrared light (850-1000 nm wavelength) . Red light is less absorbed by oxygenated blood and most of it passes through it .IR light is absorbed less by deoxygenated to low level
Ratio of Amount of red light transmitted to IR light transmitted gives you SpO2 .It is detected by a photodetector present in oximeter So when you put your finger in oximeter these things happen
Still some calibration is also done to make reading more accurate . It is calibrated to make reading more accurate by considering absorbance of tissue of your finger ,ambient light and size of your finger. There is also a curve saved in memory of Oximeter. So some calculations is carried out in its calculating unit to give you more accurate results. [That is not easy for general people ]. BUT from above discussion you have understood one thing very clearly that oximeters are designed to use with Hemoglobin .
So what about biscuits . Biscuits don't have Hb . So how you can get oxygen level for it. So let me clarify that such devices are not genuine.
Here you can see pulse rate of 150!!!!!. [ Although it took more than 3 minutes to get the result but some are showing results instantly.
now see this one is my pen .So what is its solution .
if your device not showing any result at all except for fingertip then it is absolutely good. If it is showing result after few minutes [3-4 minutes] then you can rely it upto some extent but if it is showing results instantly then go to market and buy a genuine one. What i have found untill now HICKS and BPL are found to be genuine .You can try it in shops by inserting a pen .
Share it with your dear ones and #be aware.
Stay home
Stay safe
